1
|
Kim CL, Lim SB, Choi SH, Kim DH, Sim YE, Jo EH, Kim K, Lee K, Park HS, Lim SB, Kang LJ, Jeong HS, Lee Y, Hansen CG, Mo JS. The LKB1-TSSK1B axis controls YAP phosphorylation to regulate the Hippo-YAP pathway. Cell Death Dis 2024; 15:76. [PMID: 38245531 PMCID: PMC10799855 DOI: 10.1038/s41419-024-06465-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 01/05/2024] [Accepted: 01/10/2024] [Indexed: 01/22/2024]
Abstract
The Hippo pathway's main effector, Yes-associated protein (YAP), plays a crucial role in tumorigenesis as a transcriptional coactivator. YAP's phosphorylation by core upstream components of the Hippo pathway, such as mammalian Ste20 kinase 1/2 (MST1/2), mitogen-activated protein kinase kinase kinase kinases (MAP4Ks), and their substrate, large tumor suppressor 1/2 (LATS1/2), influences YAP's subcellular localization, stability, and transcriptional activity. However, recent research suggests the existence of alternative pathways that phosphorylate YAP, independent of these core upstream Hippo pathway components, raising questions about additional means to inactivate YAP. In this study, we present evidence demonstrating that TSSK1B, a calcium/calmodulin-dependent protein kinase (CAMK) superfamily member, is a negative regulator of YAP, suppressing cellular proliferation and oncogenic transformation. Mechanistically, TSSK1B inhibits YAP through two distinct pathways. Firstly, the LKB1-TSSK1B axis directly phosphorylates YAP at Ser94, inhibiting the YAP-TEAD complex's formation and suppressing its target genes' expression. Secondly, the TSSK1B-LATS1/2 axis inhibits YAP via phosphorylation at Ser127. Our findings reveal the involvement of TSSK1B-mediated molecular mechanisms in the Hippo-YAP pathway, emphasizing the importance of multilevel regulation in critical cellular decision-making processes.
Collapse
Affiliation(s)
- Cho-Long Kim
- Department of Biomedical Sciences, Graduate School, Ajou University School of Medicine, Suwon, 16499, South Korea
| | - Su-Bin Lim
- Department of Biomedical Sciences, Graduate School, Ajou University School of Medicine, Suwon, 16499, South Korea
| | - Sue-Hee Choi
- Department of Biomedical Sciences, Graduate School, Ajou University School of Medicine, Suwon, 16499, South Korea
| | - Dong Hyun Kim
- Department of Biomedical Sciences, Graduate School, Ajou University School of Medicine, Suwon, 16499, South Korea
| | - Ye Eun Sim
- Department of Biomedical Sciences, Graduate School, Ajou University School of Medicine, Suwon, 16499, South Korea
| | - Eun-Hye Jo
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186, South Korea
| | - Keeeun Kim
- Institute of Medical Science, Ajou University School of Medicine, Suwon, 16499, South Korea
| | - Keesook Lee
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186, South Korea
| | - Hee-Sae Park
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186, South Korea
| | - Su Bin Lim
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon, 16499, South Korea
| | - Li-Jung Kang
- Three-Dimensional Immune System Imaging Core Facility, Ajou University, Suwon, 16499, South Korea
| | - Han-Sol Jeong
- Division of Applied Medicine, School of Korean Medicine, Pusan National University, Yangsan, 50612, South Korea
| | - Youngsoo Lee
- Institute of Medical Science, Ajou University School of Medicine, Suwon, 16499, South Korea
| | - Carsten G Hansen
- The University of Edinburgh, Institute for Regeneration and Repair, Centre for Inflammation Research, Edinburgh BioQuarter, Edinburgh, UK
| | - Jung-Soon Mo
- Department of Biomedical Sciences, Graduate School, Ajou University School of Medicine, Suwon, 16499, South Korea.
- Institute of Medical Science, Ajou University School of Medicine, Suwon, 16499, South Korea.
| |
Collapse
|
2
|
Kadiyska T, Tourtourikov I, Dabchev K, Madzharova D, Tincheva S, Spandidos DA, Zoumpourlis V. Role of testis‑specific serine kinase 1B in undiagnosed male infertility. Mol Med Rep 2022; 25:204. [PMID: 35485285 PMCID: PMC9073834 DOI: 10.3892/mmr.2022.12720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Accepted: 04/06/2022] [Indexed: 11/16/2022] Open
Abstract
Male infertility is a global problem affecting a considerable part of the male population. Current guidelines and practices aimed at diagnosing the cause of this problem still have low diagnostic yield. As novel candidate genes for infertility emerge, their functional role needs to be investigated in patient populations. The present study aimed to investigate testis-specific serine kinase 1B (TSSK1B), which was discovered in a previously diagnosed patient. Sanger sequencing of the coding regions and exon borders of TSSK1B was performed in a cohort of 100 male Bulgarian patients with unresolved infertility causes. Missense mutations were discovered in 10% of patients and were associated with clinical data on sperm dysmorphology. Two previously unreported mutations were discovered, p.3D>N and p.52F>L. All mutations were scored via in silico predictors and protein modelling using AlphaFold2. The present findings indicated an association between TSSK1B mutations and asthenoteratozoospermia, with further missense mutations in patients with azoospermia and teratozoospermia. Mutations in TSSK1B may be a cause of undiagnosed cases of male infertility and should be considered when molecular diagnostics are warranted.
Collapse
Affiliation(s)
- Tanya Kadiyska
- Department of Physiology and Pathophysiology, Medical University, 1413 Sofia, Bulgaria
| | | | | | | | - Savina Tincheva
- Genetic Medico‑Diagnostic Laboratory 'Genica', 1612 Sofia, Bulgaria
| | - Demetrios A Spandidos
- Laboratory of Clinical Virology, Medical School, University of Crete, Heraklion 71003, Greece
| | - Vassilis Zoumpourlis
- Biomedical Applications Unit, Institute of Chemical Biology, National Hellenic Research Foundation, 11635 Athens, Greece
| |
Collapse
|
3
|
Nayyab S, Gervasi MG, Tourzani DA, Caraballo DA, Jha KN, Teves ME, Cui W, Georg GI, Visconti PE, Salicioni AM. TSSK3, a novel target for male contraception, is required for spermiogenesis. Mol Reprod Dev 2021; 88:718-730. [PMID: 34623009 PMCID: PMC8961454 DOI: 10.1002/mrd.23539] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 09/24/2021] [Indexed: 12/27/2022]
Abstract
We have previously shown that members of the family of testis-specific serine/threonine kinases (TSSKs) are post-meiotically expressed in testicular germ cells and in mature sperm in mammals. The restricted post-meiotic expression of TSSKs as well as the importance of phosphorylation in signaling processes strongly suggest that TSSKs have an important role in germ cell differentiation and/or sperm function. This prediction has been supported by the reported sterile phenotype of the TSSK6 knock-out (KO) mice and of the double TSSK1/TSSK2 KO. The aim of this study was to develop KO mouse models of TSSK3 and to validate this kinase as a target for the development of a male contraceptive. We used CRISPR/Cas9 technology to generate the TSSK3 KO allele on B6D2F1 background mice. Male heterozygous pups were used to establish three independent TSSK3 KO lines. After natural mating of TSSK3 KO males, females that presented a plug (indicative of mating) were monitored for the following 24 days and no pregnancies or pups were found. Sperm numbers were drastically reduced in all three KO lines and, remarkably, round spermatids were detected in the cauda epididymis of KO mice. From the small population of sperm recovered, severe morphology defects were detected. Our results indicate an essential role of TSSK3 in spermiogenesis and support this kinase as a suitable candidate for the development of novel nonhormonal male contraceptives.
Collapse
Affiliation(s)
- Saman Nayyab
- Department of Veterinary & Animal Sciences and University of Massachusetts-Amherst, MA, USA
- Molecular and Cellular Biology Graduate Program, University of Massachusetts-Amherst, MA, USA
| | - María G. Gervasi
- Department of Veterinary & Animal Sciences and University of Massachusetts-Amherst, MA, USA
| | - Darya A. Tourzani
- Department of Veterinary & Animal Sciences and University of Massachusetts-Amherst, MA, USA
- Biotechnology Training Program, University of Massachusetts-Amherst, MA, USA
| | - Diego A. Caraballo
- Instituto de Ecología, Genética y Evolución (IEGEBA), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Kula N. Jha
- Division of Biotechnology Review and Research IV, Office of Biotechnology Products, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD, USA
| | - Maria E. Teves
- Department of Obstetrics and Gynecology, Virginia Commonwealth University, Richmond VA, USA
| | - Wei Cui
- Department of Veterinary & Animal Sciences and University of Massachusetts-Amherst, MA, USA
- Animal Models Core Facility, Institute for Applied Life Sciences (IALS), University of Massachusetts-Amherst, MA, USA
| | - Gunda I. Georg
- Department of Medicinal Chemistry and Institute for Therapeutics Discovery and Development, College of Pharmacy, University of Minnesota, Minneapolis, MN, USA
| | - Pablo E. Visconti
- Department of Veterinary & Animal Sciences and University of Massachusetts-Amherst, MA, USA
- Molecular and Cellular Biology Graduate Program, University of Massachusetts-Amherst, MA, USA
| | - Ana M. Salicioni
- Department of Veterinary & Animal Sciences and University of Massachusetts-Amherst, MA, USA
- Molecular and Cellular Biology Graduate Program, University of Massachusetts-Amherst, MA, USA
| |
Collapse
|
4
|
Salicioni AM, Gervasi MG, Sosnik J, Tourzani DA, Nayyab S, Caraballo DA, Visconti PE. Testis-specific serine kinase protein family in male fertility and as targets for non-hormonal male contraception†. Biol Reprod 2020; 103:264-274. [PMID: 32337545 PMCID: PMC7401350 DOI: 10.1093/biolre/ioaa064] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 04/20/2020] [Accepted: 04/24/2020] [Indexed: 11/14/2022] Open
Abstract
Male contraception is a very active area of research. Several hormonal agents have entered clinical trials, while potential non-hormonal targets have been brought to light more recently and are at earlier stages of development. The general strategy is to target genes along the molecular pathways of sperm production, maturation, or function, and it is predicted that these novel approaches will hopefully lead to more selective male contraceptive compounds with a decreased side effect burden. Protein kinases are known to play a major role in signaling events associated with sperm differentiation and function. In this review, we focus our analysis on the testis-specific serine kinase (TSSK) protein family. We have previously shown that members of the family of TSSKs are postmeiotically expressed in male germ cells and in mature mammalian sperm. The restricted postmeiotic expression of TSSKs as well as the importance of phosphorylation in signaling processes strongly suggests that TSSKs have an important role in germ cell differentiation and/or sperm function. This prediction has been supported by the reported sterile phenotype of the Tssk6 knockout (KO) mice and of the double Tssk1 and Tssk2 KO mice and by the male subfertile phenotype observed in a Tssk4 KO mouse model.
Collapse
Affiliation(s)
- Ana M Salicioni
- Department of Veterinary and Animal Sciences, University of Massachusetts-Amherst, Integrated Sciences Building 427S, 661 North Pleasant Street, Amherst MA 01003, USA
- Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, MA, USA
| | - María G Gervasi
- Department of Veterinary and Animal Sciences, University of Massachusetts-Amherst, Integrated Sciences Building 427S, 661 North Pleasant Street, Amherst MA 01003, USA
| | - Julian Sosnik
- Department of Biology, University of Massachusetts, Boston, MA, USA
| | - Darya A Tourzani
- Department of Veterinary and Animal Sciences, University of Massachusetts-Amherst, Integrated Sciences Building 427S, 661 North Pleasant Street, Amherst MA 01003, USA
- Biotechnology Training Program, University of Massachusetts, Amherst, MA, USA
| | - Saman Nayyab
- Department of Veterinary and Animal Sciences, University of Massachusetts-Amherst, Integrated Sciences Building 427S, 661 North Pleasant Street, Amherst MA 01003, USA
- Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, MA, USA
| | - Diego A Caraballo
- IFIBYNE-CONICET, Department of Physiology, Molecular and Cellular Biology, University of Buenos Aires, Buenos Aires, Argentina
| | - Pablo E Visconti
- Department of Veterinary and Animal Sciences, University of Massachusetts-Amherst, Integrated Sciences Building 427S, 661 North Pleasant Street, Amherst MA 01003, USA
- Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, MA, USA
| |
Collapse
|
5
|
Cloning and expression of Tssk1 & Tssk2 in mice and the presence & localization of them in mature sperm. Zool Res 2013; 33:381-8. [DOI: 10.3724/sp.j.1141.2012.04381] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
6
|
Li Y, Sosnik J, Brassard L, Reese M, Spiridonov NA, Bates TC, Johnson GR, Anguita J, Visconti PE, Salicioni AM. Expression and localization of five members of the testis-specific serine kinase (Tssk) family in mouse and human sperm and testis. Mol Hum Reprod 2010; 17:42-56. [PMID: 20729278 DOI: 10.1093/molehr/gaq071] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Members of the testis-specific serine/threonine kinases (Tssk) family may have a role in sperm differentiation in the testis and/or fertilization. To gain insight into the functional relevance of these kinases, their expression was examined both at the mRNA and protein levels. Quantitative PCR analysis confirmed that all five Tssk mRNAs are almost exclusively expressed postmeiotically in the testis. Recombinant mouse and human Tssks were cloned and used for validation of an array of commercial and custom-made antibodies against Tssks. Immunolocalization in mouse testis, and in mouse and human sperm, showed that Tssk1, Tssk2, Tssk4 and Tssk6, but not Tssk3, were present in mouse sperm and in germ cells from mouse testis. TSSK1, TSSK2 and TSSK6 were also detected in human sperm, while TSSK3 was absent. In both mouse and human sperm, Tssk1 was partially soluble, while Tssk2, Tssk4 and Tssk6 were insoluble in non-ionic detergents. In vitro recombinant TSSK2 activity assays showed maximum enzymatic activity at 5 mM Mg(2+) and a Km for ATP of ∼10 µM. These, observations together with findings that the Tssk1/Tssk2 double knock-out as well as the Tssk6 null mice are sterile without presenting other detectable defects, suggest that these kinases could be used as targets for male contraception.
Collapse
Affiliation(s)
- Yahui Li
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, MA, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Hermo L, Pelletier RM, Cyr DG, Smith CE. Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 3: developmental changes in spermatid flagellum and cytoplasmic droplet and interaction of sperm with the zona pellucida and egg plasma membrane. Microsc Res Tech 2010; 73:320-63. [PMID: 19941287 DOI: 10.1002/jemt.20784] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Spermiogenesis constitutes the steps involved in the metamorphosis of spermatids into spermatozoa. It involves modification of several organelles in addition to the formation of several structures including the flagellum and cytoplasmic droplet. The flagellum is composed of a neck region and middle, principal, and end pieces. The axoneme composed of nine outer microtubular doublets circularly arranged to form a cylinder around a central pair of microtubules is present throughout the flagellum. The middle and principal pieces each contain specific components such as the mitochondrial sheath and fibrous sheath, respectively, while outer dense fibers are common to both. A plethora of proteins are constituents of each of these structures, with each playing key roles in functions related to the fertility of spermatozoa. At the end of spermiogenesis, a portion of spermatid cytoplasm remains associated with the released spermatozoa, referred to as the cytoplasmic droplet. The latter has as its main feature Golgi saccules, which appear to modify the plasma membrane of spermatozoa as they move down the epididymal duct and hence may be partly involved in male gamete maturation. The end product of spermatogenesis is highly streamlined and motile spermatozoa having a condensed nucleus equipped with an acrosome. Spermatozoa move through the female reproductive tract and eventually penetrate the zona pellucida and bind to the egg plasma membrane. Many proteins have been implicated in the process of fertilization as well as a plethora of proteins involved in the development of spermatids and sperm, and these are high lighted in this review.
Collapse
Affiliation(s)
- Louis Hermo
- Department of Anatomy and Cell Biology, Faculty of Medicine, McGill University, Montreal, Quebec, Canada H3A 2B2.
| | | | | | | |
Collapse
|
8
|
Su D, Zhang W, Yang Y, Zhang H, Liu YQ, Bai G, Ma YX, Peng Y, Zhang SZ. c.822+126T>G/C: a novel triallelic polymorphism of the TSSK6 gene associated with spermatogenic impairment in a Chinese population. Asian J Androl 2009; 12:234-9. [PMID: 20037600 DOI: 10.1038/aja.2009.80] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
TSSK6 is a member of the testis-specific serine/threonine kinase family. Male Tssk6 knockout mice are infertile owing to spermatogenic impairment, including sperm count reduction, a decrease in motile sperm number and motility rates, and an increase in the number of sperms with abnormal morphology. We investigated the possible association between variations of the TSSK6 gene and spermatogenic impairment in humans. Mutation screening of TSSK6 was carried out in 519 patients with azoospermia (n = 273) or severe oligozoospermia (n = 246) and in 359 controls with normozoospermia by denaturing high-performance liquid chromatography and DNA sequencing. The frequencies of alleles and genotypes of gene polymorphism were compared between patients and controls. A novel triallelic polymorphism in TSSK6, c.822+126T>G/C, was identified. The frequencies of genotype TT and allele T were increased dramatically in infertile patients compared with controls, whereas genotype TG, allele G and allele C frequencies were significantly higher in controls than in patients. Further study revealed that the allele C frequency of controls was remarkably higher than that of patients with oligospermia. Our findings, for the first time, suggested an association of c.822+126T>G/C in TSSK6 with spermatogenic impairment in humans in which allele T may be a risk factor for male infertility, while alleles C and G may decrease susceptibility to male infertility.
Collapse
Affiliation(s)
- Dan Su
- Department of Medical Genetics, West China Hospital, West China Medical School, Sichuan University, Chengdu, China
| | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Sosnik J, Miranda PV, Spiridonov NA, Yoon SY, Fissore RA, Johnson GR, Visconti PE. Tssk6 is required for Izumo relocalization and gamete fusion in the mouse. J Cell Sci 2009; 122:2741-9. [PMID: 19596796 DOI: 10.1242/jcs.047225] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
One of the most important processes in fertilization is the fusion of egg and sperm; however, the molecular mechanisms involved in this process are not well understood. So far, using genetic approaches, only two proteins have been demonstrated to be necessary for this process: Izumo in sperm and CD9 in the egg. Here we demonstrate that sperm produced by Tssk6 (Sstk)-null mice present defects that prevent the successful fertilization of eggs in vitro and the fusion to zona-pellucida-free eggs. Tssk6 is a member of the testis-specific serine kinase family of proteins and is expressed postmeiotically in male germ cells. In order for fusion to occur, during the process known as acrosome reaction Izumo needs to relocate from the anterior head to other regions, including the postacrosomal compartment. Tssk6-null sperm fails to relocate Izumo during the acrosome reaction. Agents that interfere with actin dynamics blocked the acrosome-reaction-associated translocation of Izumo that is required for fusion in wild-type sperm. Additionally, actin polymerization was compromised in Tssk6-null sperm. Taken together, our results indicate that Tssk6 is involved in sperm-egg fusion through the regulation of actin polymerization and changes in Izumo localization.
Collapse
Affiliation(s)
- Julian Sosnik
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, MA 01003, USA
| | | | | | | | | | | | | |
Collapse
|
10
|
Baker MA, Hetherington L, Reeves GM, Aitken RJ. The mouse sperm proteome characterized via IPG strip prefractionation and LC-MS/MS identification. Proteomics 2008; 8:1720-30. [PMID: 18340633 DOI: 10.1002/pmic.200701020] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Proteomic profiling of the mouse spermatozoon has generated a unique and valuable inventory of candidates that can be mined for potential contraceptive targets and to further our understanding of the PTMs that regulate the functionality of this highly specialized cell. Here we report the identification of 858 proteins derived from mouse spermatozoa, 23 of which demonstrated testis only expression. The list contained many proteins that are known constituents of murine spermatozoa including Izumo, Spaca 1, 3, and 5, Spam 1, Zonadhesin, Spesp1, Smcp, Spata 6, 18, and 19, Zp3r, Zpbp 1 and 2, Spa17, Spag 6, 16, and 17, CatSper4, Acr, Cylc2, Odf1 and 2, Acrbp, and Acrv1. Certain protein families were highly represented in the proteome. For example, of the 42 gene products classified as proteases, 26 belonged to the 26S-proteasome. Of the many chaperones identified in this proteome, eight proteins with a TCP-1 domain were found, as were seven Rab guanosine triphosphatases. Finally, our list yielded three putative seven-transmembrane proteins, two of which have no known tissue distribution, an extragenomic progesterone receptor and three unique testis-specific kinases all of which may have some potential in the future regulation of male fertility.
Collapse
Affiliation(s)
- Mark A Baker
- The ARC Centre of Excellence in Biotechnology and Development, Reproductive Science Group, School of Environmental and Life Sciences, University of Newcastle, NSW, Australia.
| | | | | | | |
Collapse
|
11
|
Zhang Z, Shen X, Jones BH, Xu B, Herr JC, Strauss JF. Phosphorylation of mouse sperm axoneme central apparatus protein SPAG16L by a testis-specific kinase, TSSK2. Biol Reprod 2008; 79:75-83. [PMID: 18367677 DOI: 10.1095/biolreprod.107.066308] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The mammalian protein SPAG16L, the ortholog of Chlamydomonas Pf20, is an axoneme central apparatus protein necessary for flagellar motility. The SPAG16L protein sequence contains multiple potential phosphorylation sites, and the protein was confirmed to be phosphorylated in vivo. A yeast two-hybrid screen identified the testis-specific kinase, TSSK2, to be a potential SPAG16L binding partner. SPAG16L and TSSK2 interactions were confirmed by coimmunoprecipitation of both proteins from testis extracts and cell lysates expressing these proteins, and their colocalization was also noted by confocal microscopy in Chinese hamster ovary cells, where they were coexpressed. TSSK2 associates with SPAG16L via its C-terminal domain bearing WD repeats. The N-terminal domain containing a coiled coil motif does not associate with TSSK2. SPAG16L can be phosphorylated by TSSK2 in vitro. Finally, TSSK2 is absent or markedly reduced from the testes in most of the SPAG16L-null mice. These data support the conclusion that SPAG16L is a TSSK2 substrate.
Collapse
Affiliation(s)
- Zhibing Zhang
- Department of Obstetrics & Gynecology, Virginia Commonwealth University, Richmond, Virginia 23298, USA.
| | | | | | | | | | | |
Collapse
|
12
|
Bucko-Justyna M, Lipinski L, Burgering BMT, Trzeciak L. Characterization of testis-specific serine-threonine kinase 3 and its activation by phosphoinositide-dependent kinase-1-dependent signalling. FEBS J 2006; 272:6310-23. [PMID: 16336268 DOI: 10.1111/j.1742-4658.2005.05018.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The family of testis-specific serine-threonine kinases (TSSKs) consists of four members whose expression is confined almost exclusively to testis. Very little is known about their physiological role and mechanisms of action. We cloned human and mouse TSSK3 and analysed the biochemical properties, substrate specificity and in vitro activation. In vitro TSSK3 exhibited the ability to autophosphorylate and to phosphorylate test substrates such as histones, myelin basic protein and casein. Interestingly, TSSK3 showed maximal in vitro kinase activity at 30 degrees C, in keeping with it being testis specific. Sequence comparison indicated the existence of a so-called 'T-loop' within the TSSK3 catalytic domain, a structure present in the AGC family of protein kinases. To test if this T-loop is engaged in TSSK3 regulation, we mutated the critical threonine residue within the T-loop to alanine (T168A) which resulted in inactivation of TSSK3 kinase. Furthermore, Thr168 is phosphorylated in vitro by the T-loop kinase phosphoinositide-dependent protein kinase-1 (PDK1). PDK1-induced phosphorylation increased in vitro TSSK3 kinase activity, suggesting that TSSK3 can be regulated in the same way as AGC kinase family members. Analysis of peptide sequences identifies the peptide sequence RRSSSY containing Ser5 that is a target for TSSK3 phosphorylation, as an efficient and specific substrate for TSSK3.
Collapse
Affiliation(s)
- Marta Bucko-Justyna
- Department of Molecular Biology, International Institute of Molecular and Cell Biology in Warsaw, Poland
| | | | | | | |
Collapse
|
13
|
Maynard TM, Haskell GT, Lieberman JA, LaMantia AS. 22q11 DS: genomic mechanisms and gene function in DiGeorge/velocardiofacial syndrome. Int J Dev Neurosci 2002; 20:407-19. [PMID: 12175881 DOI: 10.1016/s0736-5748(02)00050-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
22q11 deletion syndrome (22qDS), also known as DiGeorge or velocardiofacial syndrome (DGS/VCFS), is a relatively common genetic anomaly that results in malformations of the heart, face and limbs. In addition, patients with 22qDS are at significant risk for psychiatric disorders as well, with one in four developing schizophrenia, and one in six developing major depressive disorders. Like several other deletion syndromes associated with psychiatric or cognitive problems, it has been difficult to determine which of the specific genes in this genomic region may mediate the syndrome. For example, patients with different genomic deletions within the 22q11 region have been found that have similar phenotypes, even though their deletions do not compromise the same set of genes. In this review, we discuss the individual genes found in the region of 22q11 that is commonly deleted in 22qDS patients, and the potential roles each of these genes may play in the syndrome. Although many of these genes are interesting candidates by themselves, we hypothesize that the full spectrum of anomalies associated with 22qDS may result from the combined result of disruptions to numerous genes within the region that are involved in similar developmental or cellular processes.
Collapse
Affiliation(s)
- Thomas M Maynard
- Department of Cell and Molecular Physiology, CB #7545, UNC School of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
| | | | | | | |
Collapse
|