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Li W, Huang Q, Zhang L, Liu H, Zhang D, Yuan S, Yap Y, Qu W, Shiang R, Song S, Hess RA, Zhang Z. A single amino acid mutation in the mouse MEIG1 protein disrupts a cargo transport system necessary for sperm formation. J Biol Chem 2021; 297:101312. [PMID: 34673028 PMCID: PMC8592874 DOI: 10.1016/j.jbc.2021.101312] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 10/08/2021] [Accepted: 10/09/2021] [Indexed: 11/22/2022] Open
Abstract
Mammalian spermatogenesis is a highly coordinated process that requires cooperation between specific proteins to coordinate diverse biological functions. For example, mouse Parkin coregulated gene (PACRG) recruits meiosis-expressed gene 1 (MEIG1) to the manchette during normal spermiogenesis. Here we mutated Y68 of MEIG1 using the CRISPR/cas9 system and examined the biological and physiological consequences in mice. All homozygous mutant males examined were completely infertile, and sperm count was dramatically reduced. The few developed sperm were immotile and displayed multiple abnormalities. Histological staining showed impaired spermiogenesis in these mutant mice. Immunofluorescent staining further revealed that this mutant MEIG1 was still present in the cell body of spermatocytes, but also that more MEIG1 accumulated in the acrosome region of round spermatids. The mutant MEIG1 and a cargo protein of the MEIG1/PACRG complex, sperm-associated antigen 16L (SPAG16L), were no longer found to be present in the manchette; however, localization of the PACRG component was not changed in the mutants. These findings demonstrate that Y68 of MEIG1 is a key amino acid required for PACRG to recruit MEIG1 to the manchette to transport cargo proteins during sperm flagella formation. Given that MEIG1 and PACRG are conserved in humans, small molecules that block MEIG1/PACRG interaction are likely ideal targets for the development of male contraconception drugs.
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Affiliation(s)
- Wei Li
- Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Qian Huang
- Department of Physiology, Wayne State University, Detroit, Michigan, USA; Department of Occupational and Environmental Health, School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Ling Zhang
- Department of Occupational and Environmental Health, School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Hong Liu
- Department of Physiology, Wayne State University, Detroit, Michigan, USA; Department of Occupational and Environmental Health, School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - David Zhang
- School of Arts and Sciences, College of William and Mary, Williamsburg, Virginia, USA
| | - Shuo Yuan
- Department of Physiology, Wayne State University, Detroit, Michigan, USA; Department of Occupational and Environmental Health, School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Yitian Yap
- Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Wei Qu
- Department of Physiology, Wayne State University, Detroit, Michigan, USA; Department of Occupational and Environmental Health, School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Rita Shiang
- Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Shizheng Song
- Department of Occupational and Environmental Health, School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Rex A Hess
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, USA
| | - Zhibing Zhang
- Department of Physiology, Wayne State University, Detroit, Michigan, USA; Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan, USA.
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Liu WS, Lu C, Mistry BV. Subcellular localization of the mouse PRAMEL1 and PRAMEX1 reveals multifaceted roles in the nucleus and cytoplasm of germ cells during spermatogenesis. Cell Biosci 2021; 11:102. [PMID: 34074333 PMCID: PMC8170798 DOI: 10.1186/s13578-021-00612-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 05/19/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Preferentially expressed antigen in melanoma (PRAME) is a cancer/testis antigen (CTA) that is predominantly expressed in normal gametogenic tissues and a variety of tumors. Members of the PRAME gene family encode leucine-rich repeat (LRR) proteins that provide a versatile structural framework for the formation of protein-protein interactions. As a nuclear receptor transcriptional regulator, PRAME has been extensively studied in cancer biology and is believed to play a role in cancer cell proliferation by suppressing retinoic acid (RA) signaling. The role of the PRAME gene family in germline development and spermatogenesis has been recently confirmed by a gene knockout approach. To further understand how PRAME proteins are involved in germ cell development at a subcellular level, we have conducted a systematic immunogold electron microscopy (IEM) analysis on testis sections of adult mice with gene-specific antibodies from two members of the mouse Prame gene family: Pramel1 and Pramex1. Pramel1 is autosomal, while Pramex1 is X-linked, both genes are exclusively expressed in the testis. RESULTS Our IEM data revealed that both PRAMEL1 and PRAMEX1 proteins were localized in various cell organelles in different development stages of spermatogenic cells, including the nucleus, rER, Golgi, mitochondria, germ granules [intermitochondrial cement (IMC) and chromatoid body (CB)], centrioles, manchette, and flagellum. Unlike other germ cell-specific makers, such as DDX4, whose proteins are evenly distributed in the expressed-organelle(s), both PRAMEL1 and PRAMEX1 proteins tend to aggregate together to form clusters of protein complexes. These complexes were highly enriched in the nucleus and cytoplasm (especially in germ granules) of spermatocytes and spermatids. Furthermore, dynamic distribution of the PRAMEL1 protein complexes were observed in the microtubule-based organelles, such as acroplaxome, manchette, and flagellum, as well as in the nuclear envelope and nuclear pore. Dual staining with PRAMEL1 and KIF17B antibodies further revealed that the PRAMEL1 and KIF17B proteins were co-localized in germ granules. CONCLUSION Our IEM data suggest that the PRAMEL1 and PRAMEX1 proteins are not only involved in transcriptional regulation in the nucleus, but may also participate in nucleocytoplasmic transport, and in the formation and function of germ cell-specific organelles during spermatogenesis.
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Affiliation(s)
- Wan-Sheng Liu
- Department of Animal Science, Center for Reproductive Biology and Health (CRBH), College of Agricultural Sciences, The Pennsylvania State University, 324 Henning Building, University Park, PA 16802 USA
| | - Chen Lu
- Department of Animal Science, Center for Reproductive Biology and Health (CRBH), College of Agricultural Sciences, The Pennsylvania State University, 324 Henning Building, University Park, PA 16802 USA
- Present Address: Fudan University, Shanghai, People’s Republic of China
| | - Bhavesh V. Mistry
- Department of Animal Science, Center for Reproductive Biology and Health (CRBH), College of Agricultural Sciences, The Pennsylvania State University, 324 Henning Building, University Park, PA 16802 USA
- Present Address: Department of Comparative Medicine, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
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Kern CH, Yang M, Liu WS. The PRAME family of cancer testis antigens is essential for germline development and gametogenesis†. Biol Reprod 2021; 105:290-304. [PMID: 33880503 DOI: 10.1093/biolre/ioab074] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 02/26/2021] [Accepted: 04/09/2021] [Indexed: 12/11/2022] Open
Abstract
Preferentially expressed antigen in melanoma (PRAME) belongs to a group of cancer/testis antigens that are predominately expressed in the testis and a variety of tumors, and are involved in immunity and reproduction. Much of the attention on PRAME has centered on cancer biology as PRAME is a prognostic biomarker for a wide range of cancers and a potential immunotherapeutic target. Less information is available about the PRAME family's function (s) during gametogenesis and in the overall reproduction process. Here, we review the current knowledge of the PRAME gene family and its function in germline development and gametogenesis. Members of the PRAME family are leucine rich repeat proteins, localized in nucleus and cytoplasm, with multifaceted roles in germ cells. As transcriptional regulators, the PRAME family proteins are involved in germline development, particularly in the maintenance of embryonic stem cell pluripotency, development of primordial germ cells, and differentiation/proliferation of spermatogenic and oogenic cells. The PRAME family proteins are also enriched in cytoplasmic organelles, such as rough endoplasmic reticulum, Golgi vesicle, germinal granules, centrioles, and play a role in the formation of the acrosome and sperm tail during spermiogenesis. The PRAME gene family remains transcriptionally active in the germline throughout the entire life cycle and is essential for gametogenesis, with some members specific to either male or female germ cells, while others are involved in both male and female gametogenesis. A potential molecular mechanism that underlies the function of PRAME, and is shared by gametogenesis and oncogenesis is also discussed.
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Affiliation(s)
- Chandlar H Kern
- Department of Animal Science, Center for Reproductive Biology and Health (CRBH), College of Agricultural Sciences, The Pennsylvania State University, University Park, PA, USA
| | - Mingyao Yang
- Department of Animal Science, Center for Reproductive Biology and Health (CRBH), College of Agricultural Sciences, The Pennsylvania State University, University Park, PA, USA
| | - Wan-Sheng Liu
- Department of Animal Science, Center for Reproductive Biology and Health (CRBH), College of Agricultural Sciences, The Pennsylvania State University, University Park, PA, USA
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Zhou L, Liu Z, Dong Y, Sun X, Wu B, Yu T, Zheng Y, Yang A, Zhao Q, Zhao D. Transcriptomics analysis revealing candidate genes and networks for sex differentiation of yesso scallop (Patinopecten yessoensis). BMC Genomics 2019; 20:671. [PMID: 31443640 PMCID: PMC6708199 DOI: 10.1186/s12864-019-6021-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 08/09/2019] [Indexed: 02/06/2023] Open
Abstract
Background The Yesso scallop, Patinopecten (Mizuhopecten) yessoensis, is a commercially important bivalve in the coastal countries of Northeast Asia. It has complex modes of sex differentiation, but knowledge of the mechanisms underlying this sex determination and differentiation is limited. Results In this study, the gonad tissues from females and males at three developmental stages were used to investigate candidate genes and networks for sex differentiation via RNA-Req. A total of 901,980,606 high quality clean reads were obtained from 18 libraries, of which 417 expressed male-specific genes and 754 expressed female-specific genes. Totally, 10,074 genes differentially expressed in females and males were identified. Weighted gene co-expression network analysis (WGCNA) revealed that turquoise and green gene modules were significantly positively correlated with male gonads, while coral1 and black modules were significantly associated with female gonads. The most important gene for sex determination and differentiation was Pydmrt 1, which was the only gene discovered that determined the male sex phenotype during early gonadal differentiation. Enrichment analyses of GO terms and KEGG pathways revealed that genes involved in metabolism, genetic and environmental information processes or pathways are sex-biased. Forty-nine genes in the five modules involved in sex differentiation or determination were identified and selected to construct a gene co-expression network and a hypothesized sex differentiation pathway. Conclusions The current study focused on screening genes of sex differentiation in Yesso scallop, highlighting the potential regulatory mechanisms of gonadal development in P. yessoensis. Our data suggested that WCGNA can facilitate identification of key genes for sex differentiation and determination. Using this method, a hypothesized P. yessoensis sex determination and differentiation pathway was constructed. In this pathway, Pydmrt 1 may have a leading function. Electronic supplementary material The online version of this article (10.1186/s12864-019-6021-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Liqing Zhou
- Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Science, Qingdao, China.,Labortory for Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Zhihong Liu
- Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Science, Qingdao, China.,Labortory for Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | | | - Xiujun Sun
- Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Science, Qingdao, China.,Labortory for Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Biao Wu
- Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Science, Qingdao, China.,Labortory for Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Tao Yu
- Changdao Enhancement and Experiment Station, Chinese Academy of Fishery Science, Changdao, China
| | - Yanxin Zheng
- Changdao Enhancement and Experiment Station, Chinese Academy of Fishery Science, Changdao, China
| | - Aiguo Yang
- Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Science, Qingdao, China. .,Labortory for Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
| | - Qing Zhao
- Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Science, Qingdao, China.,College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Dan Zhao
- Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Science, Qingdao, China.,College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
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Samofalova DO, Karpov PA, Raevsky AV, Blume YB. Protein phosphatases potentially associated with regulation of microtubules, their spatial structure reconstruction and analysis. Cell Biol Int 2017; 43:1081-1090. [PMID: 28653783 DOI: 10.1002/cbin.10810] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 06/24/2017] [Indexed: 11/12/2022]
Abstract
According to the sequence and profile comparison with known catalytic domains, where identified protein phosphatases potentially involved in regulation of microtubule dynamics and structure from Arabidopsis thaliana, Nicotiana tabacum, Medicago sativa, Oryza sativa subsp. japonica, Zea mays, and Triticum aestivum. Selected proteins were related to classical non-receptor, serine/threonine-specific and dual protein phosphatases. By application of template structures of human protein phosphatases, it was performed homology modelling of the catalytic domains of 17 plant protein phosphatases. Based on the results of the structural alignment, molecular dynamics, and conservatism in positions of functionally importance, it was confirmed homology of selected plant proteins and known protein phosphatases regulating structure and dynamics of microtubules.
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Affiliation(s)
- Dariya O Samofalova
- Institute of Food Biotechnology and Genomics, Natl. Academy of Sci. of Ukraine, Osipovskogo str. 2a, Kyiv, 04123, Ukraine
| | - Pavel A Karpov
- Institute of Food Biotechnology and Genomics, Natl. Academy of Sci. of Ukraine, Osipovskogo str. 2a, Kyiv, 04123, Ukraine
| | - Alexey V Raevsky
- Institute of Food Biotechnology and Genomics, Natl. Academy of Sci. of Ukraine, Osipovskogo str. 2a, Kyiv, 04123, Ukraine
| | - Yaroslav B Blume
- Institute of Food Biotechnology and Genomics, Natl. Academy of Sci. of Ukraine, Osipovskogo str. 2a, Kyiv, 04123, Ukraine
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Liu WS, Zhao Y, Lu C, Ning G, Ma Y, Diaz F, O'Connor M. A novel testis-specific protein, PRAMEY, is involved in spermatogenesis in cattle. Reproduction 2017; 153:847-863. [PMID: 28356500 DOI: 10.1530/rep-17-0013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 03/06/2017] [Accepted: 03/29/2017] [Indexed: 11/08/2022]
Abstract
Preferentially expressed antigen in melanoma (PRAME) is a cancer/testis antigen that is predominantly expressed in normal testicular tissues and a variety of tumors. The function of the PRAME family in spermatogenesis remains unknown. This study was designed to characterize the Y-linked PRAME (PRAMEY) protein during spermatogenesis in cattle. We found that PRAMEY is a novel male germ cell-specific, and a germinal granule-associated protein that is expressed in spermatogenic cells during spermatogenesis. The intact PRAMEY protein (58 kDa) was detected in different ages of testes but not in epididymal spermatozoa. A PRAMEY isoform (30 kDa) was highly expressed only in testes after puberty and in epididymal spermatozoa. This isoform interacts with PP1γ2 and is likely the mature protein present in the testes and sperm. Immunofluorescent staining demonstrated that PRAMEY was located predominantly in the acrosome granule of spermatids, and in acrosome and flagellum of spermatozoa. Immunogold electron microscopy further localized the PRAMEY protein complex to the nucleus and several cytoplasmic organelles, including the rough endoplasmic reticulum, some small vesicles, the intermitochondrial cement, the chromatoid body and the centrioles, in spermatogonia, spermatocytes, spermatids and/or spermatozoa. PRAMEY was highly enriched in and structurally associated with the matrix of the acrosomal granule (AG) in round spermatids, and migrated with the expansion of the AG during acrosomal biogenesis. While the function of PRAMEY remains unclear during spermatogenesis, our results suggest that PRAMEY may play an essential role in acrosome biogenesis and spermatogenesis.Free Chinese abstract: A Chinese translation of this abstract is freely available at http://www.reproduction-online.org/content/153/6/847/suppl/DC1.FreeSpanish abstract: A Spanish translation of this abstract is freely available at http://www.reproduction-online.org/content/153/6/847/suppl/DC2.
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Affiliation(s)
- Wan-Sheng Liu
- Department of Animal ScienceCenter for Reproductive Biology and Health (CRBH), College of Agricultural Sciences
| | - Yaqi Zhao
- Department of Animal ScienceCenter for Reproductive Biology and Health (CRBH), College of Agricultural Sciences
| | - Chen Lu
- Department of Animal ScienceCenter for Reproductive Biology and Health (CRBH), College of Agricultural Sciences
| | - Gang Ning
- Microscopy and Cytometry FacilityThe Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Yun Ma
- Department of Animal ScienceCenter for Reproductive Biology and Health (CRBH), College of Agricultural Sciences.,College of Life ScienceXinyang Normal University, Xinyang, Henan, China
| | - Francisco Diaz
- Department of Animal ScienceCenter for Reproductive Biology and Health (CRBH), College of Agricultural Sciences
| | - Michael O'Connor
- Department of Animal ScienceCenter for Reproductive Biology and Health (CRBH), College of Agricultural Sciences
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Construction and analysis of a human testis/sperm-enriched interaction network: Unraveling the PPP1CC2 interactome. Biochim Biophys Acta Gen Subj 2017; 1861:375-385. [DOI: 10.1016/j.bbagen.2016.11.041] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 11/10/2016] [Accepted: 11/28/2016] [Indexed: 01/01/2023]
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Brody MJ, Lee Y. The Role of Leucine-Rich Repeat Containing Protein 10 (LRRC10) in Dilated Cardiomyopathy. Front Physiol 2016; 7:337. [PMID: 27536250 PMCID: PMC4971440 DOI: 10.3389/fphys.2016.00337] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 07/20/2016] [Indexed: 12/12/2022] Open
Abstract
Leucine-rich repeat containing protein 10 (LRRC10) is a cardiomyocyte-specific member of the Leucine-rich repeat containing (LRRC) protein superfamily with critical roles in cardiac function and disease pathogenesis. Recent studies have identified LRRC10 mutations in human idiopathic dilated cardiomyopathy (DCM) and Lrrc10 homozygous knockout mice develop DCM, strongly linking LRRC10 to the molecular etiology of DCM. LRRC10 localizes to the dyad region in cardiomyocytes where it can interact with actin and α-actinin at the Z-disc and associate with T-tubule components. Indeed, this region is becoming increasingly recognized as a signaling center in cardiomyocytes, not only for calcium cycling, excitation-contraction coupling, and calcium-sensitive hypertrophic signaling, but also as a nodal signaling hub where the myocyte can sense and respond to mechanical stress. Disruption of a wide range of critical structural and signaling molecules in cardiomyocytes confers susceptibility to cardiomyopathies in addition to the more classically studied mutations in sarcomeric proteins. However, the molecular mechanisms underlying DCM remain unclear. Here, we review what is known about the cardiomyocyte functions of LRRC10, lessons learned about LRRC10 and DCM from the Lrrc10 knockout mouse model, and discuss ongoing efforts to elucidate molecular mechanisms whereby mutation or absence of LRRC10 mediates cardiac disease.
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Affiliation(s)
- Matthew J Brody
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center Cincinnati, OH, USA
| | - Youngsook Lee
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison Madison, WI, USA
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Liao RJ, Tong LJ, Huang C, Cao WW, Wang YZ, Wang J, Chen XF, Zhu WZ, Zhang W. Rescue of cardiac failing and remodelling by inhibition of protein phosphatase 1γ is associated with suppression of the alternative splicing factor-mediated splicing of Ca2+/calmodulin-dependent protein kinase δ. Clin Exp Pharmacol Physiol 2015; 41:976-85. [PMID: 25224648 DOI: 10.1111/1440-1681.12308] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 08/24/2014] [Accepted: 08/31/2014] [Indexed: 11/25/2022]
Abstract
Our previous studies showed that protein phosphatase 1γ (PP1γ) exacerbates cardiomyocyte apoptosis through promotion of Ca(2+)/calmodulin-dependent protein kinase δ (CaMKIIδ) splicing. Here we determine the role of PP1γ in abdominal aorta constriction-induced hypertrophy and remodelling in rat hearts. Systolic blood pressure and echocardiographic measurements were used to evaluate the model of cardiac hypertrophy. Sirius red staining and invasive haemodynamic/cardiac index measurements were used to evaluate the effects of PP1γ or inhibitor 1 of PP1 transfection. Western blot, reverse transcription polymerase chain reaction and co-immunoprecipitation were applied to investigate the molecular mechanisms. Transfection of PP1γ increased the value of the heart mass index, left ventricular mass index and cardiac fibrosis, and simultaneously decreased the value of maximal left ventricular pressure increase and decline rate, ejection fraction, fractional shortening, and left ventricular end-diastolic pressure, as well as left ventricular systolic pressure. Transfection of inhibitor 1 of PP1, however, showed opposite effects on the aforementioned indexes. Overexpression of PP1γ potentiated CaMKIIδC production and decreased CaMKIIδB production in the hypertrophic heart. In contrast, inhibition of PP1γ re-balanced the CaMKIIδ splicing. Furthermore, CaMKII activity was found to be augmented or attenuated by PP1γ overexpression or inhibition, respectively. Further mechanistic studies showed that abdominal aorta constriction stress specifically increased the association of alternative splicing factor with PP1γ, but not with PP1β. Overexpression of PP1γ, but not inhibitor 1 of PP1, further potentiated this association. These results suggest that PP1γ alters the cardiac hypertrophy and remodelling likely through promotion of the alternative splicing factor-mediated splicing of CaMKIIδ.
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Affiliation(s)
- Ru-Jia Liao
- Department of Pharmacology, School of Medicine, Nantong University, Nantong, China
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10
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Korrodi-Gregório L, Esteves SLC, Fardilha M. Protein phosphatase 1 catalytic isoforms: specificity toward interacting proteins. Transl Res 2014; 164:366-91. [PMID: 25090308 DOI: 10.1016/j.trsl.2014.07.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 06/26/2014] [Accepted: 07/01/2014] [Indexed: 01/21/2023]
Abstract
The coordinated and reciprocal action of serine-threonine protein kinases and protein phosphatases produces transitory phosphorylation, a fundamental regulatory mechanism for many biological processes. Phosphoprotein phosphatase 1 (PPP1), a major serine-threonine phosphatase, in particular, is ubiquitously distributed and regulates a broad range of cellular functions, including glycogen metabolism, cell cycle progression, and muscle relaxation. PPP1 has evolved effective catalytic machinery but in vitro lacks substrate specificity. In vivo, its specificity is achieved not only by the existence of different PPP1 catalytic isoforms, but also by binding of the catalytic moiety to a large number of regulatory or targeting subunits. Here, we will address exhaustively the existence of diverse PPP1 catalytic isoforms and the relevance of their specific partners and consequent functions.
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Affiliation(s)
- Luís Korrodi-Gregório
- Laboratório de Transdução de Sinais, Departamento de Biologia, Secção Autónoma de Ciências de Saúde, Centro de Biologia Celular, Universidade de Aveiro, Aveiro, Portugal
| | - Sara L C Esteves
- Laboratório de Transdução de Sinais, Departamento de Biologia, Secção Autónoma de Ciências de Saúde, Centro de Biologia Celular, Universidade de Aveiro, Aveiro, Portugal
| | - Margarida Fardilha
- Laboratório de Transdução de Sinais, Departamento de Biologia, Secção Autónoma de Ciências de Saúde, Centro de Biologia Celular, Universidade de Aveiro, Aveiro, Portugal.
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Tsai YC, Teng YN, Hung JH, Wu CH, Kuo YT, Kuo PL, Chiu CC, Huang B. Correlation between leucine rich domain and the stability of LRWD1 protein in human NT2/D1 cells. Adv Med Sci 2014; 59:266-72. [PMID: 25170821 DOI: 10.1016/j.advms.2014.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 06/13/2014] [Accepted: 07/23/2014] [Indexed: 10/24/2022]
Abstract
PURPOSE LRWD1 is a protein that contains LRR and WDs domains and is important in regulating spermatogenesis. However, the roles of LRR or WDs domains in the expression of LRWD1 remain unclear. MATERIALS AND METHODS The NT2/D1 cells separately transfected with full length of LRWD1 gene (LRWD(WT)) or genes with deleted sequences in the LRR domain (LRWD1(ΔLRR)), WD1 domain (LRWD1(ΔWD1)), WD2 domain (LRWD1(ΔWD2)), WD3 domain (LRWD1(ΔWD3)) and entire three WD domains (LRWD1(Δ3×WD)) were applied to investigate the expression levels of LRWD1 protein by either Western blot or flow cytometry. The associated proteins in these mutated LRWD1 proteins were identified by mass spectrometry. RESULTS Deletion of the LRR domain significantly decreased the expression of LRWD1 protein. With the treatment of MG132, the LRR domain may functions in preventing LRWD1 protein from proteasome-mediated degradation. In the co-immunoprecipitation analysis, protein receptor of tumor necrosis factor 2 (TNFR2) was specifically observed to be associated with LRR-deficient LRWD1 protein. CONCLUSIONS The LRR domain is significantly correlated to the stability of LRWD1 protein. Determining if the stability is modulated by TNFR2 is worthy of further study.
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Chen T, Jiang Z, Xu W, Wang Y, Li Y, Wan Y, Yuan W, Mo X, Wu X, Deng Y, Fan X, Nie D. Expression and identification of a novel gene Spata34 in mouse spermatogenic cells. Mol Biol Rep 2014; 41:1683-91. [PMID: 24435972 DOI: 10.1007/s11033-013-3017-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 12/30/2013] [Indexed: 12/14/2022]
Abstract
Leucine-rich repeat (LRR) containing proteins play an essential role in signal transduction, cell adhesion, cell development, DNA repair and RNA processing. Here we cloned a novel gene, Spata34, encoding a LRR containing protein of 415 aa. Spata34 gene consisted of 9 exons and 8 introns and mapped to chromosome 3qA3. Spata34 is conserved across species in evolution. The Spata34 gene was expressed at various levels, faintly before first weeks postpartum and strongly from 2 weeks postpartum in adult testes. Western blot analysis showed that Spata34 protein was specially expressed in mouse testis. Immunohistochemical analysis revealed that Spata34 protein was most abundant in the cytoplasm of round spermatids and elongating spermatids within seminiferous tubules of the adult testis. Overexpression of Spata34 in COS7 cells inhibited the transcriptional activity of AP-1, p53 and p21 which suggested that Spata34 protein may act as a transcriptional repressor in p53 and p21 pathway.
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Affiliation(s)
- Tingfang Chen
- College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
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Huang C, Cao W, Liao R, Wang J, Wang Y, Tong L, Chen X, Zhu W, Zhang W. PP1γ functionally augments the alternative splicing of CaMKIIδ through interaction with ASF. Am J Physiol Cell Physiol 2014; 306:C167-77. [DOI: 10.1152/ajpcell.00145.2013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Protein phosphatase 1 (PP1) and Ca2+/calmodulin-dependent protein kinase δ (CaMKIIδ) are upregulated in heart disorders. Alternative splicing factor (ASF), a major splice factor for CaMKIIδ splicing, can be regulated by both protein kinase and phosphatase. Here we determine the role of PP1 isoforms in ASF-mediated splicing of CaMKIIδ in cells. We found that 1) PP1γ, but not α or β isoform, enhanced the splicing of CaMKIIδ in HEK293T cells; 2) PP1γ promoted the function of ASF, evidenced by the existence of ASF-PP1γ association as well as the PP1γ overexpression- or silencing-mediated change in CaMKIIδ splicing in ASF-transfected HEK293T cells; 3) CaMKIIδ splicing was promoted by overexpression of PP1γ and impaired by application of PP1 inhibitor 1 (I1PP1) or pharmacological inhibitor tautomycetin in primary cardiomyocytes; 4) CaMKIIδ splicing and enhancement of ASF-PP1γ association induced by oxygen-glucose deprivation followed by reperfusion (OGD/R) were potentiated by overexpression of PP1γ and suppressed by inhibition of PP1γ with I1PP1 or tautomycetin in primary cardiomyocytes; 5) functionally, overexpression and inhibition of PP1γ, respectively, potentiated or suppressed the apoptosis and Bax/Bcl-2 ratio, which were associated with the enhanced activity of CaMKII in OGD/R-stimulated cardiomyocytes; and 6) CaMKII was required for the OGD/R induced- and PP1γ exacerbated-apoptosis of cardiomyocytes, evidenced by a specific inhibitor of CaMKII KN93, but not its structural analog KN92, attenuating the apoptosis and Bax/Bcl-2 ratio in OGD/R and PP1γ-treated cells. In conclusion, our results show that PP1γ promotes the alternative splicing of CaMKIIδ through its interacting with ASF, exacerbating OGD/R-triggered apoptosis in primary cardiomyocytes.
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Affiliation(s)
- Chao Huang
- Department of Pharmacology, School of Medicine, Nantong University, Nantong, China
| | - Wenwen Cao
- Department of Pharmacology, School of Medicine, Nantong University, Nantong, China
| | - Rujia Liao
- Department of Pharmacology, School of Medicine, Nantong University, Nantong, China
| | - Jia Wang
- Department of Pharmacology, School of Medicine, Nantong University, Nantong, China
| | - Yuzhe Wang
- Department of Pharmacology, School of Medicine, Nantong University, Nantong, China
| | - Lijuan Tong
- Department of Pharmacology, School of Medicine, Nantong University, Nantong, China
| | - Xiangfan Chen
- Department of Pharmacology, School of Medicine, Nantong University, Nantong, China
| | - Weizhong Zhu
- Cardiovascular Research Center, School of Medicine, Temple University, Philadelphia, Pennsylvania
| | - Wei Zhang
- Department of Pharmacology, School of Medicine, Nantong University, Nantong, China
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14
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DeVaul N, Wang R, Sperry AO. PPP1R42, a PP1 binding protein, regulates centrosome dynamics in ARPE-19 cells. Biol Cell 2013; 105:359-71. [PMID: 23718219 DOI: 10.1111/boc.201300019] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 05/24/2013] [Indexed: 12/20/2022]
Abstract
BACKGROUND The centrosome is the primary site for microtubule nucleation in cells and orchestrates reorganisation of the microtubule cytoskeleton during the cell cycle. The activities of the centrosome must be closely aligned with progression of the cell cycle; misregulation of centrosome separation and duplication is a hallmark of cancer. In a subset of cells, including the developing spermatid, the centrosome becomes specialised to form the basal body thereby supporting growth of the axoneme in morphogenesis of cilia and flagella, structures critical for signalling and motility. Mammalian spermatogenesis is an excellent model system to investigate the transformations in cellular architecture that accompany these changes including formation of the flagellum. We have previously identified a leucine-rich repeat protein (PPP1R42) that contains a protein phosphatase-1 binding site and translocates from the apical nucleus to the centrosome at the base of the flagellum during spermiogenesis. In this manuscript, we examine localisation and function of PPP1R42 in a ciliated epithelial cell model as a first step in understanding the role of this protein in centrosome function and flagellar formation. RESULTS We demonstrate that PPP1R42 localises to the basal body in ARPE-19 retinal epithelial cells. Co-localisation and co-immunoprecipitation experiments further show that PPP1R42 interacts with γ-tubulin. Inhibition of PPP1R42 with small interfering RNAs causes accumulation of centrosomes indicating premature centrosome separation. Importantly, the activity of two signalling molecules that regulate centrosome separation, PP1 phosphatase and NEK2 kinase, changes when PPP1R42 is inhibited: PP1 activity is reduced with a corresponding increase in NEK2 activity. CONCLUSIONS We have identified a role for the PP1-binding protein, PPP1R42, in centrosome separation in ciliated ARPE-19 cells. Our finding that inhibition of PPP1R42 expression increases the number of centrosomes per cell is consistent with our model that PPP1R42 is a positive regulator of PP1. PPP1R42 depletion reduces the activity of PP1 leading to activation of NEK2, the kinase responsible for phosphorylation of centrosomal linker proteins promoting centrosome separation. This work identifies a new molecule localised to the centrosome and basal body with a role in the complex signalling network responsible for controlling centrosome activities.
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Affiliation(s)
- Nicole DeVaul
- Department of Anatomy and Cell Biology, East Carolina University, Brody School of Medicine, Greenville, NC, USA
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Mistry BV, Zhao Y, Chang TC, Yasue H, Chiba M, Oatley J, Diaz F, Liu WS. Differential expression of PRAMEL1, a cancer/testis antigen, during spermatogenesis in the mouse. PLoS One 2013; 8:e60611. [PMID: 23565261 PMCID: PMC3614976 DOI: 10.1371/journal.pone.0060611] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 02/28/2013] [Indexed: 12/11/2022] Open
Abstract
PRAME belongs to a group of cancer/testis antigens (CTAs) that are characterized by their restricted expression in normal gametogenic tissues and a variety of tumors. The PRAME family is one of the most amplified gene families in the mouse and other mammalian genomes. Members of the PRAME gene family encode leucine-rich repeat (LRR) proteins functioning as transcription regulators in cancer cells. However, the role of PRAME in normal gonads is unknown. The objective of this study is to characterize the temporal and spatial expression of the mouse Pramel1 gene, and to determine the cellular localization of the PRAMEL1 protein during the mouse spermatogenesis. Our results indicated that the mouse Pramel1 was expressed in testis only. The mRNA and protein expression level was low in the newborn testes, and gradually increased from 1- to 3-week-old testes, and then remained constant after three weeks of age. Immunofluorescent staining on testis sections with the mouse PRAMEL1 antibody revealed that PRAMEL1 was localized in the cytoplasm of spermatocytes and the acrosomal region of round, elongating and elongated spermatids. Further analyses on the testis squash preparation and spermatozoa at a subcellular level indicated that the protein localization patterns of PRAMEL1 were coordinated with morphological alterations during acrosome formation in spermatids, and were significantly different in connecting piece, middle piece and principal piece of the flagellum between testicular and epididymal spermatozoa. Collectively, our results suggest that PRAMEL1 may play a role in acrosome biogenesis and sperm motility.
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Affiliation(s)
- Bhavesh V. Mistry
- Department of Animal Science, Center for Reproductive Biology and Health (CRBH), College of Agricultural Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Yaqi Zhao
- Department of Animal Science, Center for Reproductive Biology and Health (CRBH), College of Agricultural Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Ti-Cheng Chang
- Department of Animal Science, Center for Reproductive Biology and Health (CRBH), College of Agricultural Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Hiroshi Yasue
- National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan
| | - Mitsuru Chiba
- Division of Medical Life Sciences, Department of Biomedical Sciences, Hirosaki University Graduate School of Health Sciences, Hirosaki, Aomori, Japan
| | - Jon Oatley
- Department of Animal Science, Center for Reproductive Biology and Health (CRBH), College of Agricultural Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Francisco Diaz
- Department of Animal Science, Center for Reproductive Biology and Health (CRBH), College of Agricultural Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Wan-Sheng Liu
- Department of Animal Science, Center for Reproductive Biology and Health (CRBH), College of Agricultural Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- * E-mail:
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16
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Korrodi-Gregório L, Vieira SI, Esteves SLC, Silva JV, Freitas MJ, Brauns AK, Luers G, Abrantes J, Esteves PJ, da Cruz E Silva OAB, Fardilha M, da Cruz E Silva EF. TCTEX1D4, a novel protein phosphatase 1 interactor: connecting the phosphatase to the microtubule network. Biol Open 2013; 2:453-65. [PMID: 23789093 PMCID: PMC3654263 DOI: 10.1242/bio.20131065] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Accepted: 01/16/2013] [Indexed: 12/11/2022] Open
Abstract
Reversible phosphorylation plays an important role as a mechanism of intracellular control in eukaryotes. PPP1, a major eukaryotic Ser/Thr-protein phosphatase, acquires its specificity by interacting with different protein regulators, also known as PPP1 interacting proteins (PIPs). In the present work we characterized a physiologically relevant PIP in testis. Using a yeast two-hybrid screen with a human testis cDNA library, we identified a novel PIP of PPP1CC2 isoform, the T-complex testis expressed protein 1 domain containing 4 (TCTEX1D4) that has recently been described as a Tctex1 dynein light chain family member. The overlay assays confirm that TCTEX1D4 interacts with the different spliced isoforms of PPP1CC. Also, the binding domain occurs in the N-terminus, where a consensus PPP1 binding motif (PPP1BM) RVSF is present. The distribution of TCTEX1D4 in testis suggests its involvement in distinct functions, such as TGFβ signaling at the blood–testis barrier and acrosome cap formation. Immunofluorescence in human ejaculated sperm shows that TCTEX1D4 is present in the flagellum and in the acrosome region of the head. Moreover, TCTEX1D4 and PPP1 co-localize in the microtubule organizing center (MTOC) and microtubules in cell cultures. Importantly, the TCTEX1D4 PPP1BM seems to be relevant for complex formation, for PPP1 retention in the MTOC and movement along microtubules. These novel results open new avenues to possible roles of this dynein, together with PPP1. In essence TCTEX1D4/PPP1C complex appears to be involved in microtubule dynamics, sperm motility, acrosome reaction and in the regulation of the blood–testis barrier.
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Affiliation(s)
- Luís Korrodi-Gregório
- Laboratory of Signal Transduction, Centre for Cell Biology, Biology Department, University of Aveiro , 3810-193 Aveiro , Portugal
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Ablation of the cardiac-specific gene leucine-rich repeat containing 10 (Lrrc10) results in dilated cardiomyopathy. PLoS One 2012; 7:e51621. [PMID: 23236519 PMCID: PMC3517560 DOI: 10.1371/journal.pone.0051621] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Accepted: 11/02/2012] [Indexed: 01/06/2023] Open
Abstract
Leucine-rich repeat containing 10 (LRRC10) is a cardiac-specific protein exclusively expressed in embryonic and adult cardiomyocytes. However, the role of LRRC10 in mammalian cardiac physiology remains unknown. To determine if LRRC10 is critical for cardiac function, Lrrc10-null (Lrrc10−/−) mice were analyzed. Lrrc10−/− mice exhibit prenatal systolic dysfunction and dilated cardiomyopathy in postnatal life. Importantly, Lrrc10−/− mice have diminished cardiac performance in utero, prior to ventricular dilation observed in young adults. We demonstrate that LRRC10 endogenously interacts with α-actinin and α-actin in the heart and all actin isoforms in vitro. Gene expression profiling of embryonic Lrrc10−/− hearts identified pathways and transcripts involved in regulation of the actin cytoskeleton to be significantly upregulated, implicating dysregulation of the actin cytoskeleton as an early defective molecular signal in the absence of LRRC10. In contrast, microarray analyses of adult Lrrc10−/− hearts identified upregulation of oxidative phosphorylation and cardiac muscle contraction pathways during the progression of dilated cardiomyopathy. Analyses of hypertrophic signal transduction pathways indicate increased active forms of Akt and PKCε in adult Lrrc10−/− hearts. Taken together, our data demonstrate that LRRC10 is essential for proper mammalian cardiac function. We identify Lrrc10 as a novel dilated cardiomyopathy candidate gene and the Lrrc10−/− mouse model as a unique system to investigate pediatric cardiomyopathy.
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18
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Sperry AO. The dynamic cytoskeleton of the developing male germ cell. Biol Cell 2012; 104:297-305. [PMID: 22276751 DOI: 10.1111/boc.201100102] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Accepted: 01/20/2012] [Indexed: 11/28/2022]
Abstract
Mammalian spermatogenesis is characterised by dramatic cellular change to transform the non-polar spermatogonium into a highly polarised and functional spermatozoon. The acquisition of cell polarity is a requisite step for formation of viable sperm. The polarity of the spermatozoon is clearly demonstrated by the acrosome at the apical pole of the cell and the flagellum at the opposite end. Spermatogenesis consists of three basic phases: mitosis, meiosis and spermiogenesis. The final phase represents the period of greatest cellular change where cell-type specific organelles such as the acrosome and the flagellum form, the nucleus migrates to the plasma membrane and elongates, chromatin condenses and residual cytoplasm is removed. An important feature of spermatogenesis is the change in the cytoskeleton that occurs throughout this pathway. In this review, the author will provide an overview of these transformations and provide insight into possible modes of regulation of these rearrangements during spermatogenesis. Although primary focus will be given to the microtubule cytoskeleton, the importance of actin filaments to the cellular transformation of the male germ cell will also be discussed.
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Affiliation(s)
- Ann O Sperry
- Department of Anatomy and Cell Biology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA.
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19
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Wang R, Sperry AO. PP1 forms an active complex with TLRR (lrrc67), a putative PP1 regulatory subunit, during the early stages of spermiogenesis in mice. PLoS One 2011; 6:e21767. [PMID: 21738792 PMCID: PMC3128092 DOI: 10.1371/journal.pone.0021767] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Accepted: 06/06/2011] [Indexed: 12/29/2022] Open
Abstract
Mammalian spermatogenesis is a highly regulated developmental pathway that demands dramatic rearrangement of the cytoskeleton of the male germ cell. We have described previously a leucine rich repeat protein, TLRR (also known as lrrc67), which is associated with the spermatid cytoskeleton in mouse testis and is a binding partner of protein phosphatase-1 (PP1), an extremely well conserved signaling molecule. The activity of PP1 is modulated by numerous specific regulators of which TLRR is a candidate. In this study we measured the phosphatase activity of the TLRR-PP1 complex in the adult and the developing mouse testis, which contains varying populations of developing germ cell types, in order to determine whether TLRR acts as an activator or an inhibitor of PP1 and whether the phosphatase activity of this complex is developmentally regulated during spermatogenesis. Additionally, we assayed the ability of bacterially expressed TLRR to affect the enzymatic activity of PP1. Furthermore, we examined phosphorylation of TLRR, and elements of the spermatid cytoskeleton during the first wave of spermatogenesis in the developing testis. We demonstrate here that the TLRR complex is associated with a phosphatase activity in adult mouse testis. The relative phosphatase activity of this complex appears to reach a peak at about 21 days after birth, when pachytene spermatocytes and round spermatids are abundant in the seminiferous epithelium of the mouse testis. TLRR, in addition to tubulin and kinesin-1B, is phosphorylated during the first wave of spermatogenesis. These findings indicate that the TLRR-PP1 complex is active prior to translocation of TLRR toward the sperm flagella and that TLRR, and constituents of the spermatid cytoskeleton, may be subject to regulation by reversible phosphorylation during spermatogenesis in murine testis.
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Affiliation(s)
- Rong Wang
- Department of Anatomy and Cell Biology, Brody School of Medicine at East Carolina University, Greenville, North Carolina, United States of America
| | - Ann O. Sperry
- Department of Anatomy and Cell Biology, Brody School of Medicine at East Carolina University, Greenville, North Carolina, United States of America
- * E-mail:
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20
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Hsu CC, Chiang CW, Cheng HC, Chang WT, Chou CY, Tsai HW, Lee CT, Wu ZH, Lee TY, Chao A, Chow NH, Ho CL. Identifying LRRC16B as an oncofetal gene with transforming enhancing capability using a combined bioinformatics and experimental approach. Oncogene 2010; 30:654-67. [PMID: 21102520 DOI: 10.1038/onc.2010.451] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Oncofetal genes are expressed in embryos or fetuses, are downregulated or undetectable in adult tissues, and then re-expressed in tumors. Known oncofetal genes, such as AFP, GCB, FGF18, IMP-1 and SOX1, often have important clinical applications or pivotal biological functions. To find new oncofetal-like genes, we used the public information of expressed sequence tags to systematically analyze gene expression patterns and identified a novel oncofetal-like gene, LRRC16B. It increased the proliferation, anchorage-independent growth and tumorigenesis of transformed cells in xenografts, possibly through its effects on cyclin B1 protein levels. These findings exemplify the feasibility of using bioinformatics to find new oncofetal-like genes and suggest that more genes with important functional roles will be uncovered in the candidate gene list.
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Affiliation(s)
- C-C Hsu
- Institute of Basic Medical Science, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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Henderson H, Macleod G, Hrabchak C, Varmuza S. New candidate targets of protein phosphatase-1c-gamma-2 in mouse testis revealed by a differential phosphoproteome analysis. ACTA ACUST UNITED AC 2010; 34:339-51. [PMID: 20618881 DOI: 10.1111/j.1365-2605.2010.01085.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Reversible phosphorylation has been implicated in many developmental processes. Dephosphorylation is mediated by several families of phosphatases, including type 1 serine/threonine phosphatases (protein phosphatase-1 or PP1). The loss of the murine Ppp1cc gene causes male infertility as a result of impaired spermatogenesis. Ppp1cc encodes two splice isoforms, PPP1CC1 and PPP1CC2, with the latter being the most abundant isoform in the testis. However, the details of PPP1CC2's involvement in spermatogenesis are still unknown. As a phosphatase has been removed from the mutant mouse, a search for hyperphosphorylated proteins in the mutant testis may reveal the direct downstream targets of PPP1CC2. Using a whole tissue proteomics approach to identify testis-specific dephosphorylation targets of PPP1CC2, we found that two-dimensional electrophoresis identified 10 potential targets in the Ppp1cc null testis several of which are factors known to be important for spermatogenesis, such as HSPA2. Another potential target, tubulin, was found to be misregulated during Ppp1cc(-/-) spermatogenesis, disrupting manchette development. This work represents the first survey of the testicular phosphoproteome under pathological conditions.
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Affiliation(s)
- H Henderson
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
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