70 results match your criteria hp1 promotes

Borealin directs recruitment of the CPC to oocyte chromosomes and movement to the microtubules.

J Cell Biol 2021 Jun;220(6)

Waksman Institute and Department of Genetics, Rutgers, the State University of New Jersey, Piscataway, NJ.

The chromosomes in the oocytes of many animals appear to promote bipolar spindle assembly. In Drosophila oocytes, spindle assembly requires the chromosome passenger complex (CPC), which consists of INCENP, Borealin, Survivin, and Aurora B. To determine what recruits the CPC to the chromosomes and its role in spindle assembly, we developed a strategy to manipulate the function and localization of INCENP, which is critical for recruiting the Aurora B kinase. Read More

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orthologs MUT-7/CeWRN-1 of Werner syndrome protein regulate neuronal plasticity.

Elife 2021 Mar 1;10. Epub 2021 Mar 1.

Department of Biological Science and Technology, National Yang Ming Chiao Tung University, Hsinchu, Taiwan.

expresses human Werner syndrome protein (WRN) orthologs as two distinct proteins: MUT-7, with a 3'-5' exonuclease domain, and CeWRN-1, with helicase domains. How these domains cooperate remains unclear. Here, we demonstrate the different contributions of MUT-7 and CeWRN-1 to 22G small interfering RNA (siRNA) synthesis and the plasticity of neuronal signaling. Read More

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An embryonic stem cell-specific heterochromatin state promotes core histone exchange in the absence of DNA accessibility.

Nat Commun 2020 10 9;11(1):5095. Epub 2020 Oct 9.

Science for Life Laboratory, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Tomtebodavägen 23, 17165, Stockholm, Sweden.

Nucleosome turnover concomitant with incorporation of the replication-independent histone variant H3.3 is a hallmark of regulatory regions in the animal genome. Nucleosome turnover is known to be universally linked to DNA accessibility and histone acetylation. Read More

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October 2020

Different views of the dynamic landscape covered by the 5'-hairpin of the 7SK small nuclear RNA.

RNA 2020 09 19;26(9):1184-1197. Epub 2020 May 19.

Université de Strasbourg, Architecture et Réactivité de l'ARN - CNRS UPR 9002, Institut de Biologie Moléculaire et Cellulaire, F-67084 Strasbourg, France.

The 7SK small nuclear RNA (7SKsnRNA) plays a key role in the regulation of RNA polymerase II by sequestrating and inhibiting the positive transcription elongation factor b (P-TEFb) in the 7SK ribonucleoprotein complex (7SKsnRNP), a process mediated by interaction with the protein HEXIM. P-TEFb is also an essential cellular factor recruited by the viral protein Tat to ensure the replication of the viral RNA in the infection cycle of the human immunodeficiency virus (HIV-1). Tat promotes the release of P-TEFb from the 7SKsnRNP and subsequent activation of transcription, by displacing HEXIM from the 5'-hairpin of the 7SKsnRNA. Read More

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September 2020

Unphosphorylated STAT3 in heterochromatin formation and tumor suppression in lung cancer.

BMC Cancer 2020 Feb 22;20(1):145. Epub 2020 Feb 22.

Department of Medicine, University of California San Diego, La Jolla, CA, 92093, USA.

Background: Aberrant JAK/STAT activation has been detected in many types of human cancers. The role of JAK/STAT activation in cancer has been mostly attributed to direct transcriptional regulation of target genes by phosphorylated STAT (pSTAT), while the unphosphorylated STAT (uSTAT) is believed to be dormant and reside in the cytoplasm. However, several studies have shown that uSTATs can be found in the nucleus. Read More

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February 2020

NBS1 interacts with HP1 to ensure genome integrity.

Cell Death Dis 2019 12 13;10(12):951. Epub 2019 Dec 13.

Dipartimento di Biologia e Biotecnologie "C. Darwin", Sapienza Università di Roma, Rome, Italy.

Heterochromatin Protein 1 (HP1) and the Mre11-Rad50-Nbs1 (MRN) complex are conserved factors that play crucial role in genome stability and integrity. Despite their involvement in overlapping cellular functions, ranging from chromatin organization, telomere maintenance to DNA replication and repair, a tight functional relationship between HP1 and the MRN complex has never been elucidated. Here we show that the Drosophila HP1a protein binds to the MRN complex through its chromoshadow domain (CSD). Read More

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December 2019

CBX3 promotes glioma U87 cell proliferation and predicts an unfavorable prognosis.

J Neurooncol 2019 Oct 9;145(1):35-48. Epub 2019 Sep 9.

Department of Neurosurgery, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, 453000, Henan, People's Republic of China.

Background: Chromobox protein homolog 3 (CBX3) is one of the heterochromatin protein 1 (HP1) family members. Among multiple cancers, it is usually overexpressed. However, the mechanism and function of CBX3 in glioma remain incompletely illustrated. Read More

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October 2019

TBX2 interacts with heterochromatin protein 1 to recruit a novel repression complex to EGR1-targeted promoters to drive the proliferation of breast cancer cells.

Oncogene 2019 08 28;38(31):5971-5986. Epub 2019 Jun 28.

Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, BT9 7BL, UK.

Early Growth Response 1 (EGR1) is a stress response transcription factor with multiple tumour suppressor roles in breast tissue, whose expression is often lost in breast cancers. We have previously shown that the breast cancer oncogene TBX2 (T-BOX2) interacts with EGR1 to co-repress EGR1-target genes including the breast tumour suppressor NDRG1. Here, we show the mechanistic basis of this TBX2 repression complex. Read More

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CBX3 predicts an unfavorable prognosis and promotes tumorigenesis in osteosarcoma.

Mol Med Rep 2019 May 28;19(5):4205-4212. Epub 2019 Mar 28.

Department of Orthopedics, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, Henan 453000, P.R. China.

CBX3, namely chromobox protein homolog 3, a member of the heterochomatin protein 1 (HP1) family, has been shown to be associated with the tumorigenesis of various types of cancer. The aim of the present study was to assess the biological role and the clinicopathological importance of CBX3 in osteosarcoma. The Oncomine database was utilized to determine the CBX3 expression in sarcoma patients. Read More

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Co-dependent Assembly of Drosophila piRNA Precursor Complexes and piRNA Cluster Heterochromatin.

Cell Rep 2018 09;24(13):3413-3422.e4

Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street, Worcester, MA 01605, USA. Electronic address:

In Drosophila, the piRNAs that guide germline transposon silencing are produced from heterochromatic clusters marked by the HP1 homolog Rhino. We show that Rhino promotes cluster transcript association with UAP56 and the THO complex, forming RNA-protein assemblies that are unique to piRNA precursors. UAP56 and THO are ubiquitous RNA-processing factors, and null alleles of uap56 and the THO subunit gene tho2 are lethal. Read More

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September 2018

Histone H1 acetylation at lysine 85 regulates chromatin condensation and genome stability upon DNA damage.

Nucleic Acids Res 2018 09;46(15):7716-7730

Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China.

Linker histone H1 has a key role in maintaining higher order chromatin structure and genome stability, but how H1 functions in these processes is elusive. Here, we report that acetylation of lysine 85 (K85) within the H1 globular domain is a critical post-translational modification that regulates chromatin organization. H1K85 is dynamically acetylated by the acetyltransferase PCAF in response to DNA damage, and this effect is counterbalanced by the histone deacetylase HDAC1. Read More

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September 2018

Inflammatory factor receptor Toll-like receptor 4 controls telomeres through heterochromatin protein 1 isoforms in liver cancer stem cell.

J Cell Mol Med 2018 06 30;22(6):3246-3258. Epub 2018 Mar 30.

Research Center for Translational Medicine at Shanghai East Hospital, School of Life Science and Technology, Tongji University, Shanghai, China.

Toll-like receptor 4 (TLR4) which acts as a receptor for lipopolysaccharide (LPS) has been reported to be involved in carcinogenesis. However, the regulatory mechanism of it has not been elucidated. Herein, we demonstrate that TLR4 promotes the malignant growth of liver cancer stem cells. Read More

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Liquid droplet formation by HP1α suggests a role for phase separation in heterochromatin.

Nature 2017 07 21;547(7662):236-240. Epub 2017 Jun 21.

Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, California 94158, USA.

Gene silencing by heterochromatin is proposed to occur in part as a result of the ability of heterochromatin protein 1 (HP1) proteins to spread across large regions of the genome, compact the underlying chromatin and recruit diverse ligands. Here we identify a new property of the human HP1α protein: the ability to form phase-separated droplets. While unmodified HP1α is soluble, either phosphorylation of its N-terminal extension or DNA binding promotes the formation of phase-separated droplets. Read More

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The U6 snRNA mA Methyltransferase METTL16 Regulates SAM Synthetase Intron Retention.

Cell 2017 May;169(5):824-835.e14

Department of Microbiology, UT Southwestern Medical Center, Dallas, TX 75390, USA. Electronic address:

Maintenance of proper levels of the methyl donor S-adenosylmethionine (SAM) is critical for a wide variety of biological processes. We demonstrate that the N-adenosine methyltransferase METTL16 regulates expression of human MAT2A, which encodes the SAM synthetase expressed in most cells. Upon SAM depletion by methionine starvation, cells induce MAT2A expression by enhanced splicing of a retained intron. Read More

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Haptoglobin Hp2 Variant Promotes Premature Cardiovascular Death in Stroke Survivors.

Stroke 2017 06 9;48(6):1463-1469. Epub 2017 May 9.

From the Clinical Neurosciences, Neurology (I.P., S.M., T.P., M.K., P.L., T.E.) and Research Programs Unit, Molecular Neurology, Biomedicum Helsinki (I.P., J.S., P.L.), University of Helsinki, Finland; Department of Neurology, Helsinki University Hospital, Finland (I.P., S.M., T.P., M.K., P.L., T.E.); National Institute for Health and Welfare, Helsinki, Finland (A.J., M.J.); Minerva Foundation Institute for Medical Research, Biomedicum, Helsinki, Finland (M.J.); School of Medicine, University of Tampere, Finland (N.O., P.J.K.); and FimLab Laboratories Ltd (N.O., P.J.K.) and Division of Vascular Surgery, Department of Surgery (N.O.), Tampere University Hospital, Finland.

Background And Purpose: Haptoglobin (Hp) is an acute phase plasma protein protecting tissues from oxidative damage. It exists in 2 variant alleles () giving rise to 3 protein isoforms with different biochemical properties and efficiency to limit oxidative stress. We previously found that variant is associated with stroke risk in the patients with carotid stenosis and the risk of ischemic cardiovascular events in a general population cohort. Read More

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Independent mechanisms recruit the cohesin loader protein NIPBL to sites of DNA damage.

J Cell Sci 2017 03 6;130(6):1134-1146. Epub 2017 Feb 6.

Karolinska Institutet, Department of Cell and Molecular Biology, Stockholm 171 77, Sweden

NIPBL is required to load the cohesin complex on to DNA. While the canonical role of cohesin is to couple replicated sister chromatids together until the onset of mitosis, it also promotes tolerance to DNA damage. Here, we show that NIPBL is recruited to DNA damage throughout the cell cycle via independent mechanisms, influenced by type of damage. Read More

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HULC cooperates with MALAT1 to aggravate liver cancer stem cells growth through telomere repeat-binding factor 2.

Sci Rep 2016 10 26;6:36045. Epub 2016 Oct 26.

School of Life Science and Technology, Tongji University, Shanghai 200092, China.

The dysregulation of lncRNAs has increasingly been linked to many human diseases, especially in cancers. Our results demonstrate HULC, MALAT1 and TRF2 are highly expressed in human hepatocellular carcinoma tissues, and HULC plus MALAT1 overexpression drastically promotes the growth of liver cancer stem cells. Mechanistically, both HULC and MALAT1 overexpression enhanced RNA polII, P300, CREPT to load on the promoter region of telomere repeat-binding factor 2(TRF2), triggering the overexpression, phosphorylation and SUMOylation of TRF2. Read More

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October 2016

Intracellular MMP3 Promotes HSP Gene Expression in Collaboration With Chromobox Proteins.

J Cell Biochem 2017 01 7;118(1):43-51. Epub 2016 Jun 7.

Department of Dental Pharmacology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, 700-8525, Japan.

Matrix metalloproteinases (MMPs) are crucial factors in tumor progression, inflammatory/immune responses and tissue development/regeneration. Of note, it has been known that MMPs promote genome instability, epithelial-mesenchymal transition, invasion, and metastasis in tumor progression. We previously reported that human MMP3 could translocate into cellular nuclei and control transcription in human chondrosarcoma-derived cells and in articular cartilage (Eguchi et al. Read More

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January 2017

Double mutant P53 (N340Q/L344R) promotes hepatocarcinogenesis through upregulation of Pim1 mediated by PKM2 and LncRNA CUDR.

Oncotarget 2016 Oct;7(41):66525-66539

School of Life Science and Technology, Tongji University, Shanghai, 200092, China.

P53 is frequently mutated in human tumors as a novel gain-of-function to promote tumor development. Although dimeric (M340Q/L344R) influences on tetramerisation on site-specific post-translational modifications of p53, it is not clear how dimeric (M340Q/L344R) plays a role during hepatocarcinogenesis. Herein, we reveal that P53 (N340Q/L344R) promotes hepatocarcinogenesis through upregulation of PKM2. Read More

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October 2016

Buried territories: heterochromatic response to DNA double-strand breaks.

Acta Biochim Biophys Sin (Shanghai) 2016 Jul 4;48(7):594-602. Epub 2016 May 4.

Key Laboratory of Surgery of Zhejiang Province, Sir Run Run Shaw Hospital, Zhejiang University, Hangzhou 310016, China Institute of Translational Medicine, Zhejiang University, Hangzhou 310029, China

Cellular response to DNA double-strand breaks (DSBs), the most deleterious type of DNA damage, is highly influenced by higher-order chromatin structure in eukaryotic cells. Compared with euchromatin, the compacted structure of heterochromatin not only protects heterochromatic DNA from damage, but also adds an extra layer of control over the response to DSBs occurring in heterochromatin. One key step in this response is the decondensation of heterochromatin structure. Read More

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Red blood cell coagulation induced by low-temperature plasma treatment.

Arch Biochem Biophys 2016 09 28;605:95-101. Epub 2016 Mar 28.

Biotechnology Research Institute for Drug Discovery, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, 305-8568, Japan; Graduate School of Medicine, Chiba University, Chiba, 107-0052, Japan. Electronic address:

Low-temperature plasma (LTP) treatment promotes blood clot formation by stimulation of the both platelet aggregation and coagulation factors. However, the appearance of a membrane-like structure in clots after the treatment is controversial. Based on our previous report that demonstrated characteristics of the form of coagulation of serum proteins induced by LTP treatment, we sought to determine whether treatment with two plasma instruments, namely BPC-HP1 and PN-110/120TPG, formed clots only from red blood cells (RBCs). Read More

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September 2016

Phosphorylation of an HP1-like Protein Regulates Heterochromatin Body Assembly for DNA Elimination.

Dev Cell 2015 Dec 10;35(6):775-88. Epub 2015 Dec 10.

Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Dr. Bohr-Gasse 3, 1030 Vienna, Austria. Electronic address:

Heterochromatic loci are often assembled into higher-order heterochromatin bodies in diverse eukaryotes. However, the formation and biological roles of heterochromatin bodies are poorly understood. In the ciliated protozoan Tetrahymena, de novo heterochromatin body formation is accompanied by programmed DNA elimination. Read More

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December 2015

Patching Broken DNA: Nucleosome Dynamics and the Repair of DNA Breaks.

J Mol Biol 2016 05 26;428(9 Pt B):1846-60. Epub 2015 Nov 26.

Department of Radiation Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02132, USA. Electronic address:

The ability of cells to detect and repair DNA double-strand breaks (DSBs) is dependent on reorganization of the surrounding chromatin structure by chromatin remodeling complexes. These complexes promote access to the site of DNA damage, facilitate processing of the damaged DNA and, importantly, are essential to repackage the repaired DNA. Here, we will review the chromatin remodeling steps that occur immediately after DSB production and that prepare the damaged chromatin template for processing by the DSB repair machinery. Read More

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Escape from Mitotic Arrest: An Unexpected Connection Between Microtubule Dynamics and Epigenetic Regulation of Centromeric Chromatin in Schizosaccharomyces pombe.

Genetics 2015 Dec 28;201(4):1467-78. Epub 2015 Oct 28.

Department of Pharmacology, Rutgers Robert Wood Johnson Medical School, Piscataway, New Jersey 08854-5635 Rutgers Cancer Institute of New Jersey, New Brunswick, New Jersey 08903-2681

Accurate chromosome segregation is necessary to ensure genomic integrity. Segregation depends on the proper functioning of the centromere, kinetochore, and mitotic spindle microtubules and is monitored by the spindle assembly checkpoint (SAC). In the fission yeast Schizosaccharomyces pombe, defects in Dis1, a microtubule-associated protein that influences microtubule dynamics, lead to mitotic arrest as a result of an active SAC and consequent failure to grow at low temperature. Read More

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December 2015

SETDB1, HP1 and SUV39 promote repositioning of 53BP1 to extend resection during homologous recombination in G2 cells.

Nucleic Acids Res 2015 Sep 22;43(16):7931-44. Epub 2015 Jul 22.

University of Sussex Genome Damage and Stability Centre, East Sussex, BN19RQ, UK

Recent studies have shown that homologous recombination (HR) requires chromatin repression as well as relaxation at DNA double strand breaks (DSBs). HP1 and SUV39H1/2 are repressive factors essential for HR. Here, we identify SETDB1 as an additional compacting factor promoting HR. Read More

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September 2015

Intrinsic Toxicity of Unchecked Heterochromatin Spread Is Suppressed by Redundant Chromatin Boundary Functions in Schizosacchromyces pombe.

G3 (Bethesda) 2015 May 8;5(7):1453-61. Epub 2015 May 8.

Department of Biochemistry and Biophysics, University of California, San Francisco, California 94158

Effective boundary mechanisms halt the spread of repressive histone methylation. In the fission yeast Schizosacchromyces pombe, two factors/elements required for boundary function have been described, the jmjC protein Epe1 and binding sites for the RNA polymerase III transcription factor TFIIIC. Perplexingly, individual mutation of Epe1 or TFIIIC sites produces only mild boundary defects, and no other boundary factors have been identified. Read More

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Interaction of BARD1 and HP1 Is Required for BRCA1 Retention at Sites of DNA Damage.

Cancer Res 2015 Apr 29;75(7):1311-21. Epub 2015 Jan 29.

Department of Translational Oncology, St. Marianna University Graduate School of Medicine, Kawasaki, Japan. Division of Breast and Endocrine Surgery, Department of Surgery, St. Marianna University Graduate School of Medicine, Kawasaki, Japan.

Stable retention of BRCA1/BARD1 complexes at sites of DNA damage is required for the proper response to DNA double-strand breaks (DSB). Here, we demonstrate that the BRCT domain of BARD1 is crucial for its retention through interaction with HP1. In response to DNA damage, BARD1 interacts with Lys9-dimethylated histone H3 (H3K9me2) in an ATM-dependent but RNF168-independent manner. Read More

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RAD6 promotes homologous recombination repair by activating the autophagy-mediated degradation of heterochromatin protein HP1.

Mol Cell Biol 2015 Jan 10;35(2):406-16. Epub 2014 Nov 10.

Research Center for Translational Medicine at East Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, People's Republic of China

Efficient DNA double-strand break (DSB) repair is critical for the maintenance of genome stability. Unrepaired or misrepaired DSBs cause chromosomal rearrangements that can result in severe consequences, such as tumorigenesis. RAD6 is an E2 ubiquitin-conjugating enzyme that plays a pivotal role in repairing UV-induced DNA damage. Read More

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January 2015

A separable domain of the p150 subunit of human chromatin assembly factor-1 promotes protein and chromosome associations with nucleoli.

Mol Biol Cell 2014 Sep 23;25(18):2866-81. Epub 2014 Jul 23.

Program in Gene Function and Expression, Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605

Chromatin assembly factor-1 (CAF-1) is a three-subunit protein complex conserved throughout eukaryotes that deposits histones during DNA synthesis. Here we present a novel role for the human p150 subunit in regulating nucleolar macromolecular interactions. Acute depletion of p150 causes redistribution of multiple nucleolar proteins and reduces nucleolar association with several repetitive element-containing loci. Read More

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September 2014

Effect of the “protein diet” and bone tissue.

Nutr Hosp 2014 Jan 1;29(1):140-5. Epub 2014 Jan 1.

Biologist. Technician of the experimental nutrition lab. College of Nutrition. Master of Applied Science in Health Products (PPG-CAPS). College of Pharmacy. Federal Fluminense University. Niterói. RJ. Brazil..

Unlabelled: The aim of this study is to evaluate the effect of the hyperproteic diet consumption on bone tissue.

Methods: The study was conducted during sixty days. Twenty eight Wistar albinus rats, adults, originated from Laboratory of Experimental Nutrition were divided in four groups: (n = 7); Control 1 (C1), Control 2 (C2), Hyperproteic 1 (HP1) e Hyperproteic 2 (HP2). Read More

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January 2014