Publications by authors named "Cuiying Li"

58 Publications

Enhanced Autophagic Activity Improved the Root Growth and Nitrogen Utilization Ability of Apple Plants under Nitrogen Starvation.

Int J Mol Sci 2021 Jul 28;22(15). Epub 2021 Jul 28.

State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Shaanxi 712100, China.

Autophagy is a conserved degradation pathway for recycling damaged organelles and aberrant proteins, and its important roles in plant adaptation to nutrient starvation have been generally reported. Previous studies found that overexpression of autophagy-related (ATG) gene enhanced the autophagic activity in apple roots and promoted their salt tolerance. The expression was induced by nitrogen depletion condition in both leaves and roots of apple plants. This study aimed to investigate the differences in the growth and physiological status between wild type and -overexpressing apple plants in response to nitrogen starvation. A hydroponic system containing different nitrogen levels was used. The study found that the reduction in growth and nitrogen concentrations in different tissues caused by nitrogen starvation was relieved by overexpression. Further studies demonstrated the increased root growth and the higher nitrogen absorption and assimilation ability of transgenic plants. These characteristics contributed to the increased uptake of limited nitrogen nutrients by transgenic plants, which also reduced the starvation damage to the chloroplasts. Therefore, the -overexpressing apple plants could maintain higher photosynthetic ability and possess better growth under nitrogen starvation stress.
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http://dx.doi.org/10.3390/ijms22158085DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8348665PMC
July 2021

Overexpression of MdVQ37 reduces drought tolerance by altering leaf anatomy and SA homeostasis in transgenic apple.

Tree Physiol 2021 Jul 29. Epub 2021 Jul 29.

State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A & F University, Yangling, Shaanxi 712100, PR China.

Drought stress is an environmental factor that seriously threatens plant growth, development, and yield. VQ proteins are transcriptional regulators that have been reported to be involved in plant growth, development, and the responses to biotic and abiotic stressors. However, the relationship between VQ proteins and drought stress has not been well documented in plants. In this study, overexpressing the apple VQ motif-containing protein (MdVQ37) gene in apple plants markedly reduced the tolerance to drought. Physiological and biochemical studies further demonstrated lower enzymatic activities and decreased photosynthetic capacity in transgenic lines compared to wild-type (WT) plants under drought stress. Ultrastructural analysis of leaves showed that the leaves and palisade tissues from the transgenic lines were significantly thinner than those from WT plants. Salicylic acid (SA) analysis indicated that overexpression of MdVQ37 increased the accumulation of 2,5-DHBA by up-regulating the expression of the SA catabolic gene, which ultimately resulted to a significant reduction in endogenous SA content and the disruption of the SA-dependent signaling pathway under drought stress. Applying SA partially increased the survival rate of the transgenic lines under drought stress. These results demonstrate that the regulatory function of apple MdVQ37 is implicated in drought stress, through a change in leaf development and SA homeostasis. This study provides novel insight into understanding the multiple functions of VQ proteins.
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http://dx.doi.org/10.1093/treephys/tpab098DOI Listing
July 2021

Polymorphism of Antifolate Drug Resistance in From Local Residents and Migrant Workers Returned From the China-Myanmar Border.

Front Cell Infect Microbiol 2021 24;11:683423. Epub 2021 Jun 24.

Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China.

Drug-resistant  malaria impedes efforts to control, eliminate, and ultimately eradicate malaria in Southeast Asia. resistance to antifolate drugs derives from point mutations in specific parasite genes, including the dihydropteroate synthase (), dihydrofolate reductase (), and GTP cyclohydrolase I () genes. This study aims to investigate the prevalence and spread of drug resistance markers in populating the China-Myanmar border. Blood samples were collected from symptomatic patients with acute infection. Samples with single-clone infections were sequenced for and genesand genotyped for 6 flanking microsatellite markers. Copy number variation in the gene was also examined. Polymorphisms were observed in six different codons of the  gene (382, 383, 512, 549, 553, and 571) and six different codons of the  gene (13, 57, 58, 61, 99, 117) in two study sites. The quadruple mutant haplotypes 57I/L/58R/61M/117T of gene were the most common (comprising 76% of cases in Myitsone and 43.7% of case in Laiza). The double mutant haplotype 383G/553G of  gene was also prevalent at each site (40.8% and 31%). Microsatellites flanking the gene differentiated clinical samples from wild type and quadruple mutant genotypes ( = 0.259-0.3036), as would be expected for a locus undergoing positive selection. The lack of copy number variation of suggests that SP-resistant may harbor alternative mechanisms to secure sufficient folate.
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http://dx.doi.org/10.3389/fcimb.2021.683423DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8265503PMC
July 2021

Evaluation of Reliable Reference Genes for Erythrocyte Generation from Cord Blood CD34 Cells.

DNA Cell Biol 2021 Sep 2;40(9):1200-1210. Epub 2021 Jul 2.

Stem Cell and Regenerative Medicine Lab, Institute of Health Service and Transfusion Medicine, Beijing, China.

generation of red blood cells has the potential to circumvent shortfalls in the global demand for blood for transfusion applications. However, cell differentiation and proliferation are often regulated by precise changes in gene expression, but the underlying mechanisms and molecular changes remain unclear. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) can be used to evaluate multiple target genes. To make the results more reliable, suitable reference genes should be used to calibrate the error associated with qRT-PCR. In this study, we utilized bioinformatics to screen 3 novel candidate reference genes (calcium and integrin binding family member 2 [], olfactory receptor family 8 subfamily B member 8 [], and zinc finger protein 425 []) along with eight traditional reference genes (glyceraldehyde-3-phosphate dehydrogenase [], β-actin [], , β2-microglobulin [], peptidylprolyl isomerase A [], TATA box-binding protein [], hydroxymethylbilane synthase [], and hypoxanthine phosphoribosyltransferase 1 []). Two software algorithms (geNorm and NormFinder) were used to evaluate the stability of expression of the 11 genes at different stages of erythrocyte development. Comprehensive analysis showed that expression of and was the most stable, whereas and were the least suitable candidate genes. These results suggest that appropriate reference genes should be selected before performing gene expression analysis during erythroid differentiation and that and are suitable reference genes for gene expression studies on erythropoiesis.
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http://dx.doi.org/10.1089/dna.2021.0185DOI Listing
September 2021

Increasing proportions of relapsing parasite species among imported malaria in China's Guangxi Province from Western and Central Africa.

Travel Med Infect Dis 2021 Sep-Oct;43:102130. Epub 2021 Jun 21.

Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, Yunnan Province, 650500, China. Electronic address:

Background: Travel-related malaria in non-endemic areas returning from endemic areas presents important challenges to diagnosis and treatment. Imported malaria to newly malaria-free countries poses further threats of malaria re-introduction and potential resurgence. For those traveling to places with high Plasmodium falciparum prevalence, prophylaxis against this parasite is recommended, whereas causal prophylaxis against relapsing malaria is often overlooked.

Methods: We analyzed a cluster of imported malaria among febrile patients in Shanglin County, Guangxi Province, China, who had recent travel histories to Western and Central Africa. Malaria was diagnosed by microscopy and subsequently confirmed by species- and subspecies-specific PCR. Plasmodium vivax was genotyped using a barcode consisting of 42 single nucleotide polymorphisms.

Results: Investigations of 344 PCR-confirmed malaria cases revealed that in addition to Plasmodium falciparum being the major parasite species, the relapsing parasites Plasmodium ovale and P. vivax accounted for ~40% of these imported cases. Of the 114 P. ovale infections, 65.8% and 34.2% were P. ovale curtisi and P. ovale wallikeri, respectively, with the two subspecies having a ~2:1 ratio in both Western and Central Africa. Phylogenetic analysis of 14 P. vivax isolates using a genetic barcode demonstrated that 11 formed a distinct clade from P. vivax populations from Eastern Africa.

Conclusion: This study provides support for active P. vivax transmission in areas with the predominant Duffy-negative blood group. With relapsing malaria making a substantial proportion of the imported malaria, causal prophylaxis should be advocated to travelers with a travel destination to Western and Central Africa.
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http://dx.doi.org/10.1016/j.tmaid.2021.102130DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8429216PMC
June 2021

Insights into the effect of human civilization on Malus evolution and domestication.

Plant Biotechnol J 2021 Jun 23. Epub 2021 Jun 23.

State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling, China.

The evolutionary history of the Malus genus has not been well studied. In the current study, we presented genetic evidence on the origin of the Malus genus based on genome sequencing of 297 Malus accessions, revealing the genetic relationship between wild species and cultivated apples. Our results demonstrated that North American and East Asian wild species are closer to the outgroup (pear) than Central Asian species, and hybrid species including natural (separated before the Pleistocene, about 2.5 Mya) and artificial hybrids (including ornamental trees and rootstocks) are between East and Central Asian wild species. Introgressions from M. sylvestris in cultivated apples appeared to be more extensive than those from M. sieversii, whose genetic background flowed westward across Eurasia and eastward to wild species including M. prunifolia, M. × asiatica, M. × micromalus, and M. × robust. Our results suggested that the loss of ancestral gene flow from M. sieversii in cultivated apples accompanied the movement of European traders around the world since the Age of Discovery. Natural SNP variations showed that cultivated apples had higher nucleotide diversity than wild species and more unique SNPs than other apple groups. An apple ERECTA-like gene that underwent selection during domestication on 15 chromosome was identified as a likely major determinant of fruit length and diameter, and an NB-ARC domain-containing gene was found to strongly affect anthocyanin accumulation using a genome-wide association approach. Our results provide new insights into the origin and domestication of apples and will be useful in new breeding programmes and efforts to increase fruit crop productivity.
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http://dx.doi.org/10.1111/pbi.13648DOI Listing
June 2021

Effect of Lycopene on Oral Squamous Cell Carcinoma Cell Growth by Inhibiting IGF1 Pathway.

Cancer Manag Res 2021 26;13:723-732. Epub 2021 Jan 26.

Central Laboratory, Peking University School and Hospital of Stomatology, Beijing 100081, People's Republic of China.

Purpose: Lycopene has produced robust clinical effects and shows a promising chemopreventive in the oral cancer and precancerous lesions. However, much is still unknown about its mechanisms of the carotenoid in protecting against oral squamous cell carcinoma (OSCC). Insulin-like growth factor 1 (IGF1) pathway serves as a key regulatory signal pathway in the tumor microenvironment, which may be associated with the angiogenesis, tumorigenicity, and cancer proliferation. The current study was focused on elucidating the potential pathway played for lycopene to exert its function in treating with OSCC.

Materials And Methods: Firstly, we explored the dose- and time-response of CAL-27 and WSU-HN6 cells to lycopene. Both cells were incubated with various concentrations of lycopene (0.25, 0.5, 1, 2 µM). The inhibiting rate of cell proliferation was assessed using MTT assay. To observe the regulating effect of lycopene on OSCC, cell migration, apoptosis and tumor formation were detected in vitro and in vivo. The potential signaling pathways of OSCC cells treated with lycopene were analyzed by Affymetrix microarrays. And then, we investigated the changing of IGF1 signaling pathway, on the protein levels of tumor tissue after lycopene.

Results: Cell proliferation was inhibited by lycopene in a dose- and time-dependent manner. The optimum inhibition efficiencies for OSCC cells were also found. Further, the results also demonstrated that pre-treatment of OSCC with lycopene drastically induced cell apoptosis suppresses cell migration and tumor growth. Mechanistically, ingenuity pathway analysis further revealed that IGF1 pathway participate in killing effects on OSCC after treatment of lycopene. Lycopene may inhibit the pathway by regulating protein expression of IGF1, IGF binding protein (BP) 1, IGFBP3, transcription factor Jun/AP-1 (JUN), and forkhead box O1 (FOXO1).

Conclusion: These observations indicate that lycopene regulates OSCC cell growth by inhibiting IGF1 pathway, which may be a promising agent for the treatment of OSCC.
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http://dx.doi.org/10.2147/CMAR.S283927DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7847369PMC
January 2021

Diagnostic Value of Contrast-Enhanced Ultrasound for Differential Diagnosis of Malignant and Benign Soft Tissue Masses: A Meta-Analysis.

Ultrasound Med Biol 2020 12 6;46(12):3179-3187. Epub 2020 Sep 6.

Department of Ultrasound, First Affiliated Hospital of Nanjing Medical University, Nanjing, China. Electronic address:

This meta-analysis was aimed at investigating the value of using contrast-enhanced ultrasound (CEUS) in the differential diagnosis of benign and malignant soft tissue masses (STMs). Relevant studies published before March 24, 2020 were identified through a comprehensive search of PubMed, Ovid, Cochrane and Web of Science. According to the inclusion criteria, five studies were selected comprising 746 patients. In the differential diagnosis of benign and malignant STMs, the pooled sensitivity and specificity of CEUS were 76% (95% confidence interval [CI]: 71%-81%; heterogeneity [I] = 74.5%) and 67% (95% CI: 62%-71%; I = 36.5%), respectively. The diagnostic odds ratio was 7.37 (95% CI: 3.78%-14.35; I = 66.6%). The overall area under the curve was 0.77 (standard error: 0.0392). Subgroup analysis revealed that different index tests of CEUS resulted in different diagnostic performance. Importantly, CEUS is an effective method for the differential diagnosis between benign and malignant STMs.
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http://dx.doi.org/10.1016/j.ultrasmedbio.2020.08.011DOI Listing
December 2020

MdWRKY30, a group IIa WRKY gene from apple, confers tolerance to salinity and osmotic stresses in transgenic apple callus and Arabidopsis seedlings.

Plant Sci 2020 Oct 25;299:110611. Epub 2020 Jul 25.

State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A & F University, Yangling, Shaanxi 712100, China. Electronic address:

Abiotic stresses threaten the productivity and quality of economically important perennial fruit crops such as apple (Malus × domestica Borkh.). WRKY transcription factors play various roles in plant responses to abiotic stress, but little is known regarding WRKY genes in apple. Here, we carried out functional characterization of an apple Group IIa WRKY gene (MdWRKY30). qRT-PCR analysis found that MdWRKY30 expression was induced by salt and drought stress. A subcellular localization assay showed that MdWRKY30 is localized to the nucleus. A transactivation assay found that MdWRKY30 has no transcriptional activation activity. A Y2H assay indicated that MdWRKY26, MdWRKY28, and MdWRKY30 interact with each other to form heterodimers and homodimers. Transgenic analysis revealed that the overexpression of MdWRKY30 in Arabidopsis enhanced salt and osmotic tolerance in the seedling stage, as well as during the seed germination and greening cotyledon stages. MdWRKY30 overexpression enhanced tolerance to salt and osmotic stresses in transgenic apple callus through transcriptional regulation of stress-related genes. Together, our results demonstrate that MdWRKY30 is an important regulator of salinity and osmotic stress tolerance in apple.
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http://dx.doi.org/10.1016/j.plantsci.2020.110611DOI Listing
October 2020

Overexpression of MdATG18a enhances alkaline tolerance and GABA shunt in apple through increased autophagy under alkaline conditions.

Tree Physiol 2020 10;40(11):1509-1519

State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China.

Soil alkalization affects apple production in northwest China. Autophagy is a highly conserved degradative protein pathway in eukaryotes. Autophagy in plants can be activated by various abiotic factors. We previously identified the positive role of the autophagy-related gene MdATG18a in drought, nitrogen deficiency and resistance to Diplocarpon mali infection in apple. However, it is still unclear whether ATG18a is related to alkaline stress. In this study, we used hydroponic culture to simulate alkaline stress and found that the overexpression of MdATG18a significantly improved the tolerance of apple to alkaline stress. The overexpression of MdATG18a increased biomass, photosynthetic rate and antioxidant capacity of transgenic plants compared with wild-type plants under alkaline stress. The overexpression of MdATG18a promoted γ-aminobutyric acid (GABA) shunt via an increase in glutamate (GABA precursor) and GABA contents and upregulation of GABA shunt-related genes. In addition, the overexpression of MdATG18a significantly upregulated the expression of other core ATG genes and increased the formation of autophagosomes under alkaline stress. In conclusion, these results suggest that the overexpression of MdATG18a in apple enhances alkaline tolerance and the GABA shunt, which may be owing to the increase in autophagic activity.
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http://dx.doi.org/10.1093/treephys/tpaa075DOI Listing
October 2020

Molecular Surveillance and in vitro Drug Sensitivity Study of Isolates from the China-Myanmar Border.

Am J Trop Med Hyg 2020 09;103(3):1100-1106

Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China.

The emergence and spread of resistance in to the frontline treatment artemisinin-based combination therapies in Southeast Asia require close monitoring of the situation. Here, we collected 36 clinical samples of from the China-Myanmar border in 2014-2016, adapted these parasites to continuous culture, and performed in vitro drug assays on seven antimalarial drugs. Data for 23 parasites collected in 2010 and 2012 from the same area reported in an early study were used to assess longitudinal changes in drug sensitivity. Parasites remained highly resistant to chloroquine (CQ) and pyrimethamine, whereas they were generally sensitive to mefloquine (MFQ), lumefantrine (LMF), naphthoquine (NQ), and pyronaridine (PND). Parasites showed a similar temporal trend in sensitivity to CQ, NQ, and PND, with gradual reduction in the half-maximal inhibitory concentrations (ICs) after 2012. The ICs to the aminoalcohol drugs MFQ, LMF, and quinine (QN) all significantly declined in 2014, followed by various degrees of increase in 2016. Pyrimethamine displayed a continuous increase in IC over the years. The Dd2-like mutations were fixed or nearly fixed in the parasite population. The F1226Y mutation was detected in 80% parasites in 2016 and associated with reduced sensitivity to LMF and QN ( < 0.05). The N51I in and K540E/N and A581G in that are associated with antifolate resistance were either fixed or were approaching fixation in recent years. This study provides an updated picture and temporal trend of antimalarial drug resistance in the China-Myanmar border region, which will serve as a reference for antimalarial treatment.
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http://dx.doi.org/10.4269/ajtmh.20-0235DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7470591PMC
September 2020

Ex vivo susceptibilities of Plasmodium vivax isolates from the China-Myanmar border to antimalarial drugs and association with polymorphisms in Pvmdr1 and Pvcrt-o genes.

PLoS Negl Trop Dis 2020 06 12;14(6):e0008255. Epub 2020 Jun 12.

Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States of America.

Background: Vivax malaria is an important public health problem in the Greater Mekong Subregion (GMS), including the China-Myanmar border. Previous studies have found that Plasmodium vivax has decreased sensitivity to antimalarial drugs in some areas of the GMS, but the sensitivity of P. vivax to antimalarial drugs is unclear in the China-Myanmar border. Here, we investigate the drug sensitivity profile and genetic variations for two drug resistance related genes in P. vivax isolates to provide baseline information for future drug studies in the China-Myanmar border.

Methodology/principal Findings: A total of 64 P. vivax clinical isolates collected from the China-Myanmar border area were assessed for ex vivo susceptibility to eight antimalarial drugs by the schizont maturation assay. The medians of IC50 (half-maximum inhibitory concentrations) for chloroquine, mefloquine, pyronaridine, piperaquine, quinine, artesunate, artemether, dihydroartemisinin were 84.2 nM, 34.9 nM, 4.0 nM, 22.3 nM, 41.4 nM, 2.8 nM, 2.1 nM and 2.0 nM, respectively. Twelve P. vivax clinical isolates were found over the cut-off IC50 value (220 nM) for chloroquine resistance. In addition, sequence polymorphisms in pvmdr1 (P. vivax multidrug resistance-1), pvcrt-o (P. vivax chloroquine resistance transporter-o), and difference in pvmdr1 copy number were studied. Sequencing of the pvmdr1 gene in 52 samples identified 12 amino acid substitutions, among which two (G698S and T958M) were fixed, M908L were present in 98.1% of the isolates, while Y976F and F1076L were present in 3.8% and 78.8% of the isolates, respectively. Amplification of the pvmdr1 gene was only detected in 4.8% of the samples. Sequencing of the pvcrt-o in 59 parasite isolates identified a single lysine insertion at position 10 in 32.2% of the isolates. The pvmdr1 M908L substitutions in pvmdr1 in our samples was associated with reduced sensitivity to chloroquine, mefloquine, pyronaridine, piperaquine, quinine, artesunate and dihydroartemisinin.

Conclusions: Our findings depict a drug sensitivity profile and genetic variations of the P. vivax isolates from the China-Myanmar border area, and suggest possible emergence of chloroquine resistant P. vivax isolates in the region, which demands further efforts for resistance monitoring and mechanism studies.
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http://dx.doi.org/10.1371/journal.pntd.0008255DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7314094PMC
June 2020

Targeting human cytomegalovirus IE genes by CRISPR/Cas9 nuclease effectively inhibits viral replication and reactivation.

Arch Virol 2020 Aug 7;165(8):1827-1835. Epub 2020 Jun 7.

Beijing Key Laboratory of Blood Safety and Supply Technologies, Beijing, 100850, P.R. China.

Human cytomegalovirus (HCMV) infection causes high morbidity and mortality among immunocompromised patients and can remain in a latent state in host cells. Expression of the immediate-early (IE) genes sustains HCMV replication and reactivation. As a novel genome-editing tool, the clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9) system has been extensively utilized to modify and edit genomic DNA. In the present study, the CRISPR/Cas9 system was used to target the IE region of the HCMV genome via specific single-guide RNAs (sgRNAs). Infection with CRISPR/Cas9/sgRNA lentiviral constructs significantly reduced viral gene expression and virion production in HFF primary fibroblasts and inhibited viral DNA production and reactivation in the THP-1 monocytic cell line. Thus, the CRISPR/Cas9/sgRNA system can accurately and efficiently target HCMV replication and reactivation and represents a novel therapeutic strategy against latent HCMV infection.
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http://dx.doi.org/10.1007/s00705-020-04687-3DOI Listing
August 2020

Comparison of the osteoblastic activity of low elastic modulus Ti-24Nb-4Zr-8Sn alloy and pure titanium modified by physical and chemical methods.

Mater Sci Eng C Mater Biol Appl 2020 Aug 25;113:111018. Epub 2020 Apr 25.

Central Laboratory, Peking University School and Hospital of Stomatology, #22 Zhongguancun South Avenue, Haidian District, Beijing 100081, China. Electronic address:

Ti-24Nb-4Zr-8Sn (Ti2448) alloy is a novel low elastic modulus β-titanium alloy without toxic elements. It also has the advantage of high strength, so it has potential application prospects for implantation. To develop its osteogenic effects, it can be modified by electrochemical, and physical processes. The main research aim of this study was to explore the bioactivity of Ti2448 alloy modified by sandblasted, large-grit, acid-etched (SLA), micro-arc oxidation (MAO) and anodic oxidation (AO), and to determine which of the three surface modifications is the best way for developing the osteogenesis of bone marrow mesenchymal stem cells (BMMSCs). In vitro studies, the cytoskeleton, focal adhesion and proliferation of BMMSCs showed that both pure titanium and Ti2448 alloy have good biocompatibility. The osteogenic differentiation of BMMSCs with the Ti2448 alloy were examined by detecting alkaline phosphatase (ALP), mineralization nodules and osteogenic proteins and were better than that with pure titanium. These results showed that the Ti2448 alloy treated by SLA has a better effect on osteogenesis than pure titanium, and AO is the best way of three surface treatments to improve osteogenesis in this study.
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http://dx.doi.org/10.1016/j.msec.2020.111018DOI Listing
August 2020

Gene Expression Profile Reveals Hematopoietic-Related Molecule Changes in Response to Hypoxic Exposure.

DNA Cell Biol 2020 Apr 6;39(4):548-554. Epub 2020 Mar 6.

Department of Blood Transfusion, Air Force Medical Center, PLA, Beijing, P.R. China.

The Qing-Tibet Plateau is characterized by low oxygen pressure, which is an important biomedical and ecological stressor. However, the variation in gene expression during periods of stay on the plateau has not been well studied. We recruited eight volunteers to stay on the plateau for 3, 7, and 30 days. Human Clariom D arrays were used to measure transcriptome changes in the mRNA expression profiles in these volunteers' blood. Analysis of variance (ANOVA) indicated that 699 genes were significantly differentially expressed in response to entering the plateau during hypoxic exposure. The genes with changes in transcript abundance were involved in the terms phosphoprotein, acetylation, protein binding, and protein transport. Furthermore, numerous genes involved in hematopoietic functions, including erythropoiesis and immunoregulation, were differentially expressed in response to hypoxia. This phenomenon may be one of reasons why the majority of people entering the plateau do not have excessive erythrocyte proliferation and are susceptible to infection.
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http://dx.doi.org/10.1089/dna.2019.5004DOI Listing
April 2020

Genetically Engineered Escherichia coli Nissle 1917 Secreting GLP-1 Analog Exhibits Potential Antiobesity Effect in High-Fat Diet-Induced Obesity Mice.

Obesity (Silver Spring) 2020 02;28(2):315-322

Department of Neurosurgery, PLA Strategic Support Force Characteristic Medical Center, Beijing, P.R. China.

Objective: This study aimed to investigate the potential antiobesity effect of genetically modified Escherichia coli Nissle 1917 (EcN-GM) in mice fed a high-fat diet (HFD).

Methods: The mice were randomly divided into six groups: a normal diet group (ND), a HFD group, a HFD + EcN group, and three HFD + EcN-GM groups. The effects of EcN-GM on body weight, food intake, fat pad and organ weight, and an oral glucose tolerance test were measured, in addition to hepatic biochemistry and histological analysis. The mRNA expression of neuropeptides related to food intake regulation in the hypothalamus was also detected.

Results: The results showed that EcN-GM decreased body weight, body weight gain, food intake, fat pad weight, and hepatic weight of HFD mice. There were beneficial effects of EcN-GM on blood glucose, hepatic biochemistry, and hepatic histological alterations. A dramatic switch of food intake-regulating gene expression in the hypothalamus was also observed in mice.

Conclusions: This work has revealed that a modified live bacterial therapeutic, EcN-GM, has potential beneficial effects on obesity. This effect may be related to the regulating of the neuropeptide expression of energy intake and expenditure in the hypothalamus. This study demonstrates a successful example of engineered EcN-GM as a novel approach for weight management.
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http://dx.doi.org/10.1002/oby.22700DOI Listing
February 2020

Exogenous Dopamine Application Promotes Alkali Tolerance of Apple Seedlings.

Plants (Basel) 2019 Dec 7;8(12). Epub 2019 Dec 7.

State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shanxi 712100, China.

Arid and semiarid apple producing areas suffer from severe alkalinity of soil, which strongly affects the yield and quality of apples. Dopamine (DA) is involved in metabolic activities in response to abiotic stress in plants. To detect the effects of exogenous DA application on the adaption of apple () seedlings to alkali stress and as a protection from oxidative stress, 0.1 mM DA was identified as the most suitable concentration by hydroponic culture. Further experimentation showed that the growth and photosynthesis of apple seedlings were significantly inhibited under alkali stress, and more reactive oxygen species accumulated, compared with control. However, exogenous DA application suppressed the loss of the plant height, root length, chlorophyll levels, and photosynthetic capacity of apple seedlings that were caused by alkali stress. In the leaves of alkali stressed seedlings, the catalase, superoxide dismutase, and peroxidase activities were lower and hydrogen peroxide and malondialdehyde levels were higher than in the untreated plants. The presence of DA significantly alleviated such effects of alkali stress. In addition, exogenous DA application increased the antioxidant capacity of apple seedlings under alkali stress by increasing the level of chlorogenic acid. These results are significant for improving the alkali tolerance of apple in apple-producing areas with alkalized soil.
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http://dx.doi.org/10.3390/plants8120580DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6963653PMC
December 2019

Widespread resistance mutations to sulfadoxine-pyrimethamine in malaria parasites imported to China from Central and Western Africa.

Int J Parasitol Drugs Drug Resist 2020 04 29;12:1-6. Epub 2019 Nov 29.

Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, PR China. Electronic address:

Background: Imported cases of infectious disease provide invaluable information about epidemiological conditions abroad, and should guide treatment decisions at home and abroad. Here, we examined cases of malaria imported from Africa to China for mutations eroding the efficacy of sulfadoxine-pyrimethamine (SP), sometimes used as an intermittent preventive treatment during for pregnant women and infants.

Methods: A total of 208 blood samples were collected from P. falciparum-infected workers who had returned from Western and Central Africa to Guangxi Province Frequency distribution. Samples were analyzed for the mutations in dhfr and dhps genes by PCR -sequencing. The prevalence of dhfr and dhps polymorphisms was analyzed. Among the isolates, polymorphisms were detected in mutants N51I, C59R, S108N and I164L of Pfdhfr and I431V, S436 A/F, A437G, K540 E/N, A581G and A613T of pfdhps.

Results: Mutations promoting drug resistance were widespread in this cohort. For pfdhfr and pfdhps, wild types were equally rare among patients returned from Western Africa and Central Africa. A triple-mutant dhfr haplotype was most prevalent (>70%). We report for the first time mutation I164L-dhfr and I431V-dhps in Ghana, and for the first time we found A581G to exceed a clinically-relevant threshold that may counter-indicate current clinical practices. For Pfdhps, the double-mutant IAGKAA was high prevalent haplotype in Ghana, Western Africa. The single-mutant ISGKAA was a majority haplotype in Cameroon. Alarmingly, a "super resistance" quintuple mutant was detected, for the first time, in parasites of West African origin (defined by IAGKAA/IRNI in combination with pfdhps 581G and dhfr I164L). This may limit the efficacy of this drug combination for even intermittent clinical applications.

Conclusions: These data are cause for great concern and call for continued surveillance of the efficacy of SP in source and recipient populations, and should be considered when developing treatment policy for imported malaria cases in China and elsewhere.
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http://dx.doi.org/10.1016/j.ijpddr.2019.11.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6909128PMC
April 2020

Comparative Proteomic Analysis Reveals Key Proteins Linked to the Accumulation of Soluble Sugars and Organic Acids in the Mature Fruits of the Wild Species.

Plants (Basel) 2019 Nov 11;8(11). Epub 2019 Nov 11.

State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China.

Soluble sugars and organic acids are the main determinants of fruit organoleptic quality. To investigate the genes responsible for the soluble sugar and organic acid contents of apple fruits, a label-free proteomic analysis involving liquid chromatography (LC)-mass spectrometry (MS)/MS was conducted with the fruits of two species, and , which exhibit significant differences in soluble sugar and organic acid contents. A total of 13,036 unique peptides and 1,079 differentially-expressed proteins were identified. To verify the LC-MS/MS results, five candidate proteins were further analyzed by parallel reaction monitoring. The results were consistent with the LC-MS/MS data, which confirmed the reliability of the LC-MS/MS analysis. The functional annotation of the differentially-expressed proteins, based on the gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, revealed that they were mainly related to biological processes and cellular components. Additionally, the main enriched KEGG pathways were related to metabolic processes. Moreover, 31 proteins involved in soluble sugar metabolism, organic acid metabolism, and H-transport were identified. The results of this study may be useful for the comprehensive characterization of the complex mechanism regulating apple fruit-soluble sugar and organic acid contents.
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http://dx.doi.org/10.3390/plants8110488DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6918222PMC
November 2019

Genetic changes in the gene between Tibetan and Han ethnic groups and adaptation to the plateau hypoxic environment.

PeerJ 2019 28;7:e7943. Epub 2019 Oct 28.

Department of Blood Transfusion, Air Force Medical Center, PLA, Beijing, China.

In the Chinese Han population, prolonged exposure to hypoxic conditions can promote compensatory erythropoiesis which improves hypoxemia. However, Tibetans have developed unique phenotypes, such as downregulation of the hypoxia-inducible factor pathway through gene mutation, thus the mechanism of adaption of the Han population should be further studied. The results indicated that, under plateau hypoxic conditions, the plains population was able to acclimate rapidly to hypoxia through increasing mRNA expression and changing the hemoglobin conformation. Furthermore, the mutant genotype frequencies of the rs13419896, rs1868092 and rs4953354 loci in the gene were significantly higher in the Tibetan population than in the plains population. The gene expression level was lowest in the Han population carrying the A-A homozygous mutant of the rs13419896 locus but that it increased rapidly after these individuals entered the plateau. At this time, the hemoglobin content was lower in the homozygous mutant Han group than in the wild-type and heterozygous mutant populations, and the viscosity of blood was reduced in populations carrying the A-A haplotypes in rs13419896 and rs1868092 Among Tibetans, the group carrying homozygous mutations of the three SNPs also had lower hemoglobin concentrations than the wild-type. The Raman spectroscopy results showed that exposure of the Tibetan and Han population to hypoxic conditions changed the spatial conformation of hemoglobin and its binding ability to oxygen. The Tibetan population has mainly adapted to the plateau through genetic mutations, whereas some individuals adapt through changes in hemoglobin structure and function.
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http://dx.doi.org/10.7717/peerj.7943DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6822597PMC
October 2019

Efficacy of directly-observed chloroquine-primaquine treatment for uncomplicated acute Plasmodium vivax malaria in northeast Myanmar: A prospective open-label efficacy trial.

Travel Med Infect Dis 2020 Jul - Aug;36:101499. Epub 2019 Oct 8.

Department of Internal Medicine, Morsani College of Medicine, University of South Florida, 3720 Spectrum Blvd, Suite 304, Tampa, FL, 33612, USA. Electronic address:

Background: Chloroquine (CQ) and primaquine (PQ) remain the frontline drugs for radical cure of uncomplicated P. vivax malaria in the Greater Mekong Sub-region (GMS). Recent reports of decreased susceptibility of P. vivax to CQ in many parts of the GMS raise concerns.

Methods: From April 2014 to September 2016, 281 patients with uncomplicated P. vivax infection attending clinics in border settlements for internally displaced people in northeast Myanmar were recruited into this study. Patients were treated with standard regimen of 3-day CQ and concurrent 14-day PQ (3.5 mg/kg total dose) as directly observed therapy, and followed for recurrent parasitemia within 28 days post-patency.

Results: Within the 28-day follow-up period, seven patients developed recurrent parasitemia, resulting in a cumulative rate of parasite recurrence of 2.6%. Five of the seven parasitemias recurred within two weeks, and two of those failed to clear within seven days, indicating high-grade resistance.

Conclusion: Although failure of CQ/PQ treatment of P. vivax was relatively infrequent in northeast Myanmar, this study nonetheless confirms that CQ/PQ-resistant strains do circulate in this area, some of them of a highly resistant phenotype. It is thus recommended that patients who acquire vivax malaria in Myanmar be treated an artemisinin-combination therapy along with hypnozoitocidal primaquine therapy to achieve radical cure.
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http://dx.doi.org/10.1016/j.tmaid.2019.101499DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7816571PMC
August 2021

Increasing trends of malaria in a border area of the Greater Mekong Subregion.

Malar J 2019 Sep 12;18(1):309. Epub 2019 Sep 12.

Division of Infectious Diseases and International Medicine, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, 3720 Spectrum Boulevard, Suite 304, Tampa, FL, 33612, USA.

Background: Intensive malaria transmission along international borders is a significant impediment to malaria elimination in the Greater Mekong Subregion (GMS) of Southeast Asia. Passive case detection (PCD) was used to study the dynamics and trends of malaria transmission at the China-Myanmar border to provide epidemiologic information for improved malaria control.

Methods: PCD was conducted in one hospital and 12 clinics near the Laiza town in northeast Myanmar from 2011 to 2016. Clinical malaria was diagnosed by microscopy and demographic information was captured using a structured questionnaire at the time of the patient's presentation for care.

Results: Over the study period, 6175 (19.7%) malaria cases were confirmed by microscopy from 31,326 suspected cases. The four human malaria parasite species were all identified, with Plasmodium vivax and Plasmodium falciparum accounting for 5607 (90.8%) and 481 (7.8%) of the confirmed cases, respectively. In contrast to the steady decline of malaria in the general GMS, the study site had an upward trend of malaria incidence with vivax malaria outbreaks in 2013 and 2016. Adult males, children under the age of 15, and those with occupations such as farming, being a soldier or student, had significantly higher risks of clinical malaria compared to having fevers from other aetiologies. A self-reported history of clinical malaria was also associated with a higher risk of confirmed malaria.

Conclusions: The China-Myanmar border area has experienced an overall upward trend of malaria incidence in recent years with P. vivax becoming the predominant species. Evidence-based control strategies need to focus on high-risk populations.
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http://dx.doi.org/10.1186/s12936-019-2924-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6739967PMC
September 2019

Genome-wide identification of drought-responsive microRNAs in two sets of from interspecific hybrid progenies.

Hortic Res 2019 8;6:75. Epub 2019 Jun 8.

State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100 China.

Drought stress can negatively impact apple fruit quality and yield. Apple microRNAs (miRNAs) participate in apple tree and fruit development, as well as in biotic stress tolerance; however, it is largely unknown whether these molecules are involved in the drought response. To identify drought-responsive miRNAs in , we first examined the drought stress tolerance of ten F progenies of R3 (. × ) × . We performed Illumina sequencing on pooled total RNA from both drought-tolerant and drought-sensitive plants. The sequencing results identified a total of 206 known miRNAs and 253 candidate novel miRNAs from drought-tolerant plants and drought-sensitive plants under control or drought conditions. We identified 67 miRNAs that were differentially expressed in drought-tolerant plants compared with drought-sensitive plants under drought conditions. Under drought stress, 61 and 35 miRNAs were differentially expressed in drought-tolerant and drought-sensitive plants, respectively. We determined the expression levels of seven out of eight miRNAs by stem-loop qPCR analysis. We also predicted the target genes of all differentially expressed miRNAs and identified the expression of some genes. Gene Ontology analyses indicated that the target genes were mainly involved in stimulus response and cellular and metabolic processes. Finally, we confirmed roles of two miRNAs in apple response to mannitol. Our results reveal candidate miRNAs and their associated mRNAs that could be targeted for improving drought tolerance in species, thus providing a foundation for understanding the molecular networks involved in the response of apple trees to drought stress.
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http://dx.doi.org/10.1038/s41438-019-0157-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6555824PMC
June 2019

Factors that influence ultrasound evaluation of breast tumor size.

Med Ultrason 2019 May;21(2):144-151

Department of Breast Surgery, The First Affiliated Hospital with Nanjing Medical University, Nanjing, Jiangsu Key Lab of CancerBiomarkers, Prevention and Treatment, Jiangsu Collaborative Innovation Center For Cancer Personalized Medicine, School of Public Health, Nanjing Medical University, Nanjing, China.

Aims: To determine the factors influencing ultrasound breast tumor size assessment accuracy.

Material And Methods:  Five factors (tumor type, molecular subtype, histological size, histological grade, and breast density) were used to assess the measurement accuracy of breast ultrasound in tumor size. Size underestimation was defined as ultrasound index lesion diameter < histological size by at least 5 mm.

Results: Breast ultrasound underestimated tumor size significantly, especially in cases with intraductal components (p=0.002). There was a tendency for higher size underestimation in breast cancer tumors with high-histological grade (p=0.03), human epidermal growth factor receptor type 2 (HER2)-overexpressing breast cancer tumors (p=0.02) and hormone receptor (HR)-/HER2+ breast cancer tumors (p=0.008). Furthermore, core biopsy revealedhigher probability of size underestimation with intraductal components (p=0.002). Size underestimation was more frequent with larger histological size (p<0.001). Masses in non-dense breasts were significantly underestimated (p=0.036) compared to dense breasts.

Conclusions: The size underestimation was influenced by pathological type, molecular subtype, and histological size. The pathological results of core biopsy were conducive for predicting tumor size pre-surgery in precise breast cancer diagnosis.
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http://dx.doi.org/10.11152/mu-1747DOI Listing
May 2019

In vitro susceptibility of Plasmodium falciparum isolates from the China-Myanmar border area to artemisinins and correlation with K13 mutations.

Int J Parasitol Drugs Drug Resist 2019 08 10;10:20-27. Epub 2019 Apr 10.

Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, Yunnan Province, 650500, China. Electronic address:

Mutations in the Kelch domain of the K13 gene (PF3D7_1343700) were previously associated with artemisinin resistance in Plasmodium falciparum. This study followed the dynamics of the K13 polymorphisms in P. falciparum parasites from the China-Myanmar border area obtained in 2007-2016, and their in vitro sensitivities to artesunate (AS) and dihydroartemisinin (DHA). The 50% effective concentration (EC) values of 133 culture-adapted field isolates to AS and DHA, measured by the conventional 72 h SYBR Green I-based assay, varied significantly among the parasites from different years; all were significantly higher than that of the reference strain 3D7. Compared with parasites from 2007 to 2008, ring survival rates almost doubled in parasites obtained in later years. Sequencing the full-length K13 genes identified 11 point mutations present in 85 (63.9%) parasite isolates. F446I was the predominant (55/133) variant, and its frequency was increased from 17.6% (3/17) in 2007 to 55.9% (19/34) in 2014-2016. No wild-type (WT) Kelch domain sequences were found in the 34 samples obtained from 2014 to 2016. In the 2014-2016 samples, a new mutation (G533S) appeared and reached 44.1% (15/34). Collectively, parasites with the Kelch domain mutations (after amino acid 440) had significantly higher ring survival rates than the WT parasites. Individually, F446I, G533S and A676D showed significantly higher ring survival rates than the WT. Although the drug sensitivity phenotypes measured by the RSA and EC assays may be intrinsically linked to the in vivo clinical efficacy data, the values determined by these two assays were not significantly correlated. This study identified the trend of K13 mutations in parasite populations from the China-Myanmar border area, confirmed an overall correlation of Kelch domain mutations with elevated ring-stage survival rates, and emphasized the importance of monitoring the evolution and spread of parasites with reduced artemisinin sensitivity along the malaria elimination course.
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http://dx.doi.org/10.1016/j.ijpddr.2019.04.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6479106PMC
August 2019

Effects of motivational methods on oral hygiene of orthodontic patients: A systematic review and meta-analysis.

Medicine (Baltimore) 2018 Nov;97(47):e13182

Central Laboratory, Peking University School and Hospital of Stomatology, Haidian District, Beijing, China.

Objective: The aim of our study was to qualitatively and quantitatively synthesize the evidence regarding ways to improve motivation of oral hygiene among orthodontic patients with fixed appliances and identify the effects of motivational methods via comparing the oral hygiene condition before and after the motivations.

Methods: An electronic search was conducted in PubMed, Ovid, Embase, and the Crochrane Library for relevant random controlled trials (RCT) and clinical controlled trial (CCT) published before May 1, 2017 with manual search in addition. Search and selection of studies, quality assessment, data extraction and synthesis was completed by 2 reviewers independently. Plaque index (PI) and gingival index (GI) at 1, 3, 6-month were pooled with Review Manager 5.3. Bias of included studies was evaluated.

Results: In total, 12 studies fulfilled the inclusion criteria of this systematic review, of which, 5 were included in the meta-analysis. Motivational methods had statistically significant advantage regarding PI in the experimental group over control group at 1, 3, 6-month, while GI was significantly better controlled in the study group at 3, 6-month. The quality of included studies was moderate.

Conclusion: It is worthy for orthodontists to put in additional efforts to motivate patients to maintain good oral hygiene throughout the entire treatment process.
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http://dx.doi.org/10.1097/MD.0000000000013182DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6392669PMC
November 2018

Exogenous myo-inositol alleviates salinity-induced stress in Malus hupehensis Rehd.

Plant Physiol Biochem 2018 Dec 1;133:116-126. Epub 2018 Nov 1.

State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, 712100, PR China. Electronic address:

Myo-inositol mediates various physiological processes and stress responses. Here, we investigated its role in Malus hupehensis Rehd. plants when grown hydroponically under saline conditions. Salt-stressed plants showed reduced growth and marked declines in photosynthetic activity and chlorophyll concentrations. However, pretreatment with 50 μM myo-inositol significantly alleviated those inhibitions and enabled plants to maintain their photosynthetic capacity. In addition to changing stomatal behavior, exogenous myo-inositol inhibited ROS accumulation and Na uptake. In contrast, activities of antioxidant systems were enhanced, and expression was elevated for genes involved in Na uptake (e.g., HKT1, NHX1, SOS1, and SOS2). This exogenous application also provoked the accumulation of sugars or sugar alcohols, which partially contributed to the maintenance of osmotic balance, and the scavenging of ROS, either directly or indirectly. In summary, myo-inositol appears to alleviate the salt-induced inhibition of physiological processes for M. hupehensis, not only by supporting the plant's antioxidant defense system but also by mediating Na and K homeostasis and the osmotic balance.
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http://dx.doi.org/10.1016/j.plaphy.2018.10.037DOI Listing
December 2018

Determination of Predominant Organic Acid Components in Species: Correlation with Apple Domestication.

Metabolites 2018 Oct 31;8(4). Epub 2018 Oct 31.

State Key Laboratory of Crop Stress Biology for Arid Areas, Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling 712100, China.

Significant variation in organic acid components was detected in mature fruits of 101 apple accessions using high-performance liquid chromatography. The species predominantly accumulated malic acid and citric acid, whereas wild fruits exhibited significantly higher levels of organic acid content than that in cultivated fruits. Differential accumulation patterns during fruit developmental stages was detected between malic acid and citric acid, thus suggesting a complex genetic regulation mechanism of organic acid metabolism in apple fruit. A highly positive correlation was detected between fruit total organic acid content with malic acid and citric acid content, thus suggesting that malic acid and citric acid are the principal determinants of apple fruit acidity. In contrast to malic acid, citric acid was predominantly detected in partial wild apples, while extremely low to undetectable concentrations of citric acid were observed in cultivated apple fruits; this is likely due to the genetic effects of parental characters. Our results provide vital information that could be useful for future studies on genetic analysis and improvement of organic acid accumulation in apple fruits.
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http://dx.doi.org/10.3390/metabo8040074DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6316603PMC
October 2018

Genome-wide Identification, Classification, Molecular Evolution and Expression Analysis of Malate Dehydrogenases in Apple.

Int J Mol Sci 2018 Oct 24;19(11). Epub 2018 Oct 24.

State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China.

Malate dehydrogenase plays crucial roles in energy homeostasis, plant development and cold and salt tolerance, as it mediates the reversible conversion of malate to oxaloacetate. However, the evolutionary pattern of genes in apple remains elusive. In this study, a total of 20 genes were identified from the "Golden Delicious" apple draft genome. We revealed the physiological and biochemical properties, gene structure, and conserved motifs of genes. Chromosomal localization and / ratio analysis of genes revealed different selective pressures acted on duplicated genes. Exploration of the phylogenetic relationships revealed six clades and similar frequencies between old and recent duplications, and significant differences in the evolutionary rates of the gene family were observed. One gene, MDP0000807458, which was highly expressed during apple fruit development and flower bud differentiation, was under positive selection. Thus, we speculated that MDP0000807458 is a likely candidate gene involved in regulation of flower bud differentiation and organic acid metabolism in apple fruits. This study provides a foundation for improved understanding of the molecular evolution of genes and further facilitates the functional analysis of MDP0000807458 to unravel its exact role in flower bud differentiation and organic acid metabolism.
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http://dx.doi.org/10.3390/ijms19113312DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6274877PMC
October 2018

Genome-Wide Identification and Analysis of Apple NITRATE TRANSPORTER 1/PEPTIDE TRANSPORTER Family (NPF) Genes Reveals MdNPF6.5 Confers High Capacity for Nitrogen Uptake under Low-Nitrogen Conditions.

Int J Mol Sci 2018 Sep 14;19(9). Epub 2018 Sep 14.

State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A & F University, Yangling 712100, China.

The NITRATE TRANSPORTER 1/PEPTIDE TRANSPORTER family (NPF) proteins play important roles in moving substrates such as nitrate, peptides, amino acids, dicarboxylates, malate, glucosinolates, indole acetic acid (IAA), abscisic acid (ABA), and jasmonic acid. Although a unified nomenclature of NPF members in plants has been reported, this gene family has not been studied as thoroughly in apple ( × Borkh.) as it has in other species. Our objective was to provide general information about apple s and analyze the transcriptional responses of some members to different levels of nitrate supplies. We identified 73 of these genes from the apple genome and used phylogenetic analysis to organize them into eight major groups. These apple NPFs are structurally conserved, based on alignment of amino acid sequences and analyses of phylogenetics and conserved domains. Examination of their genomic structures indicated that these genes are highly conserved among other species. We monitored 14 cloned s that showed varied expression patterns under different nitrate concentrations and in different tissues. Among them, was significantly induced by both low and high levels of nitrate. When compared with the wild type, transgenic apple calli were more tolerant to low-N stress, which demonstrated that this gene confers greater capacity for nitrogen uptake under those conditions. We also analyzed the expression patterns of those 73 genes in various tissues. Our findings benefit future research on this family of genes.
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http://dx.doi.org/10.3390/ijms19092761DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6164405PMC
September 2018
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