Richard is a young dedicated scholar, born and raised in Kenya, in eastern part of the African continent. I hold the following in the realm of the academic spheres, First class honors in Bachelor of Education, chemistry and biology option, masters of science in plants Eco-physiology, and now PhD in plant molecular breeding and genetics.
My passion is to find a lasting solution to drought stress, thus will help in solving myriad of human problems and intern reduce the purge of hunger, currently being experience in almost in global scale.
Primary Affiliation: State Key Laboratory of Cotton Biology/Institute of Cotton Research - Anyang, Henan , China
PubMed Central Citations
College of Food Science and Engineering
Chengdu University of Technology
Graduate School Chinese Academy of Agricultural Sciences (GSCAAS), Beijing
Michigan State University
University of Pittsburgh
Institute of Cotton Research of Chinese Academy of Agricultural Sciences/State Key Laboratory of Cotton Biology
State Key Laboratory of Cotton Biology
7PubMed Central Citations
G3 (Bethesda) 2018 07 2;8(7):2483-2500. Epub 2018 Jul 2.
Research Base in Anyang Institute of Technology, State Key Laboratory of Cotton Biology/Institute of Cotton Research, Chinese Academy of Agricultural Science, Anyang 455000, Henan, China
G3 Genes Genomes Genetics
ABSTRACT Late embryogenesis abundant (LEA) proteins play key roles in plant drought tolerance. In this study, 157, 85 and 89 candidate LEA2 proteins were identified in G. hirsutum, G. arboreum and G. raimondii respectively. LEA2 genes were classified into 6 groups, designated as group 1 to 6. Phylogenetic tree analysis revealed orthologous gene pairs within the cotton genome. The cotton specific LEA2 motifs identified were E, R and D in addition to Y, K and S motifs. The genes were distributed on all chromosomes. LEA2s were found to be highly enriched in non-polar, aliphatic amino acid residues, with leucine being the highest, 9.1% in proportion. The miRNA, ghr-miR827a/b/c/d and ghr-miR164 targeted many genes are known to be drought stress responsive. Various stress-responsive regulatory elements, ABA-responsive element (ABRE), Drought-responsive Element (DRE/CRT), MYBS and low-temperature-responsive element (LTRE) were detected. Most genes were highly expressed in leaves and roots, being the primary organs greatly affected by water deficit. The expression levels were much higher in G. tomentosum as opposed to G. hirsutum. The tolerant genotype had higher capacity to induce more of LEA2 genes. Over expression of the transformed gene Cot_AD24498 showed that the LEA2 genes are involved in promoting root growth and in turn confers drought stress tolerance. We therefore infer that Cot_AD24498, CotAD_20020, CotAD_21924 and CotAD_59405 could be the candidate genes with profound functions under drought stress in upland cotton among the LEA2 genes. The transformed Arabidopsis plants showed higher tolerance levels to drought stress compared to the wild types. There was significant increase in antioxidants, catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD) accumulation, increased root length and significant reduction in oxidants, Hydrogen peroxide (H2O2) and malondialdehyde (MDA) concentrations in the leaves of transformed lines under drought stress condition. This study provides comprehensive analysis of LEA2 proteins in cotton thus forms primary foundation for breeders to utilize these genes in developing drought tolerant genotypes.
Int J Mol Sci 2018 May 30;19(6). Epub 2018 May 30.
State Key Laboratory of Cotton Biology/Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, China.
Genes (Basel) 2018 Apr 12;9(4). Epub 2018 Apr 12.
Research Base in Anyang Institute of Technology, State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Science (ICR, CAAS), Anyang 455000, Henan, China.
J. Plant Breed. Genet. 05 (02) 2017. 57-73
ournal of Plant Breeding and Genetics
Cotton is a moderately salt-tolerant crop, but its salt tolerance threshold is not more than 7.7 ds·m−1. The seedling stage of cotton is the highly sensitive to salinity and the effects can be quantified by measuring morphological and physiological traits. The purpose of this study was to identify QTLs related with salinity tolerance at seedling stage. Meanwhile where they were localized in the genome, investigate the relationships between the traits at seedling stage under salt and to find candidate genes related with salt tolerance. To achieve this goal, two upland cotton accessions mainly cultivated in China; CCRI-35 (Source: 132062) tolerant to salinity as female parent and Nan Dan Ba Di Da Hua: NH (Source: 130549) sensitive to salinity as male parent and their 277 offspring F2:3 population have been used. Our experiment revealed 05 consistent QTLs found in at least two environments. Only 02 major QTLs with high phenotypic variation explained by a single QTL, R2 (%), and high percentage of heritability, HB (%), values were detected on chromosome Chr1 and Chr 7/ Chr16.These QTLs explained phenotypic variation from 5.7 to 60.03 %. Broad sense heritability was high for SL (83.1%) and moderate for GR (68.4). These 02 major QTLs and the 26 genes identified in this study could be used in cotton breeding program and with few obstacles.
G3 Genes Genomes Genetics
The extrusion of toxins and substances at cellular level is a vital survival life process in plants under abiotic stress. The multidrug and toxic compound extrusion (MATE) gene family is largely involved in the exportation of toxins and other substrates. We undertook to carry out the genome-wide analysis of MATE gene families in Gossypium raimondii and Gossypium arboreum and assessed their expression levels under salt, cadmium and drought stresses. We identified 70 and 68 MATE genes in G. raimondii and G. arboreum respectively. Majority of the genes were predicted to be localized within the plasma membrane with a few being distributed in other cell parts. Based on phylogenetic analysis, the genes were subdivided into three subfamilies designated as M1, M2 and M3. Closely related members shared similar gene structures, thus were highly conserved in nature and found to have evolved majorly through purifying selection. The genes were distributed in all the chromosomes. Twenty-nine gene duplication events were detected, with segmental type being the dominant. GO annotation revealed the link to salt, drought and cadmium stresses. The genes exhibited differential expression, with GrMATE18, GrMATE34, GaMATE41 and GaMATE51 were significantly up regulated under drought, salt and cadmium stress, and possibly could be the candidate genes. The results of this study provide the very first information on the genome wide and functional characterization of MATE genes in diploid cotton. The results therefore would be important for breeders in the development of more stress tolerant cotton genotypes.
Int. J. Mol. Sci. 2018, 19, 1614; doi:10.3390/ijms19061614
International Journal of Molecular Sciences
Cotton production is on the decline due to ever-changing environmental conditions. Drought and salinity stress contribute to over 30% of total loss in cotton production, the situation has worsened more due to the narrow genetic base of the cultivated upland cotton. The genetic diversity of upland cotton has been eroded over the years due to intense selection and inbreeding. To break the bottleneck, the wild cotton progenitors offer unique traits which can be introgressed into the cultivated cotton, thereby improving their performance. In this research, we developed a BC2F2 population between wild male parent, G. tomentosum as the donor, known for its high tolerance to drought and the elite female parent, G. hirsutum as the recurrent parent, which is high yielding but sensitive to drought stress. The population was genotyped through the genotyping by sequencing (GBS) method, in which 10,888 single-nucleotide polymorphism (SNP) s were generated and used to construct a genetic map. The map spanned 4191.3 cM, with average marker distance of 0.3849 cM. The map size of the two sub genomes had a narrow range, 2149 cM and 2042.3 cM for At and Dt_sub genomes respectively. A total of 66,434 genes were mined, with 32,032 (48.2%) and 34,402 (51.8%) genes being obtained within the At and Dt_sub genomes respectively. Pkinase (PF00069) was found to be the dominant domain, with 1069 genes. Analysis of the main sub family, serine threonine protein kinases through gene ontology (GO), cis element and miRNA targets analysis revealed that most of the genes were involved in various functions aimed at enhancing abiotic stress tolerance. Further analysis of the RNA sequence data and qRT-PCR validation revealed 16 putative genes, which were highly up regulated under drought stress condition, and were found to be targeted by ghr-miR169a and ghr-miR164, previously associated with NAC(NAM, ATAF1/2 and CUC2) and myeloblastosis (MYB), the top rank drought stress tolerance genes. These genes can be exploited further to aid in development of more drought tolerant cotton genotypes. Keywords: cotton; drought; genetic diversity; genotyping by sequencing; backcross