tailieunhanh - Báo cáo khoa học: Characterization of testis-specific serine–threonine kinase 3 and its activation by phosphoinositide-dependent kinase-1-dependent signalling

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. | iFEBS Journal Characterization of testis-specific serine-threonine kinase 3 and its activation by phosphoinositide-dependent kinase-1-dependent signalling Marta Bucko-Justyna1 Leszek Lipinski1 2 Boudewijn M. Th. Burgering3 and Lech Trzeciak1 1 Department of Molecular Biology International institute of Molecular and Cell Biology in Warsaw Poland 2 Laboratory of Molecular Medicine Institute of Biochemistry and Biophysics Polish Academy of Sciences Warsaw Poland 3 Department of PhysiologicalChemistry and Center for BiomedicalGenetics University MedicalCenter Utrecht the Netherlands Keywords activation loop PDK1 serine-threonine kinase testis specific TSSK3 Correspondence B. M. Th. Burgering Department of Physiological Chemistry and Center for BiomedicalGenetics University Medical Center Utrecht Universiteitsweg 100 3584 CG Utrecht the Netherlands Fax 31 30 253 9035 Tel 31 30 253 8918 E-mail L. Trzeciak Department of Molecular Biology International institute of Molecular and Cell Biology in Warsaw Ks Trojdena 4 OZ-109 Warsaw Poland Fax 48 22 5970743 Tel 48 22 5970748 E-mail leszek3@ M. Bucko-Justyna and L. Lipinski contributed equally to this work. Received 2 June 2005 revised 3 October 2005 accepted 17 October 2005 doi 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 C in keeping with it being testis specific. Sequence comparison indicated the existence of a so-called T-loop within the TSSK3 catalytic .