Spergen-1 Might Be an Adhesive Molecule Associated with Mitochondria in the Middle Piece of Spermatozoa

Developmental Biology

Hiroshi Iida¹  Masamichi Doiguchi¹  Yosaburo Shibata¹  Takayuki Mori¹  Kiyotaka Toshimori¹ 

[1] Laboratory of Zoology, Graduate School of Agriculture, Kyushu University, Higashiku Hakozaki 6-10-1, Fukuoka, 812-8581, Japan

关键词: spergen-1;    spermiogenesis;    mitochondria;    spermatids;    mitochondrial sheath;    spermatozoa;    testis;    spermatogenesis;   

DOI  :  10.1006/dbio.2002.0833

学科分类：生物科学（综合）

来源: Academic Press

【 摘 要 】

Spergen-1,arecentlyidentifiedmoleculespecificallyexpressedinhaploidspermatidsintestis,isasmallproteinof154aminoacidswithamitochondria-targetingsignalattheNterminus.Toexaminethelocalizationofspergen-1proteiningermcells,weperformedimmunocytochemistrywiththeanti-spergen-1antibodyonfrozensectionsofrattestisandpurifiedspermatozoa.Immunolabelingforspergen-1wasdetectedinmitochondriaofelongatingspermatidsandofthemiddlepiecesofmaturedspermatozoa.Immunoelectronmicroscopyrevealedthatspergen-1waslocalizedtothesurfaceofmitochondriainthemiddlepieceofspermatozoa.Toinvestigatethepropertiesofspergen-1,COS-7cellsweretransfectedwithvectorsencodingvariousspergen-1mutants.Thetransfectionexperimentsshowedthatspergen-1expressedinthecellstendedtoagglutinatemitochondriaandassemblethemintoaggregationsandthattheC-terminalregionofspergen-1aswellastheN-terminalmitochondrialtargetingsignalwasrequisiteforinductionofmitochondrialaggregation.Theseresultssuggestthatspergen-1,amitochondria-associatedmoleculeinspermatozoa,hasapropertytoinducemitochondrialaggregationatleastinculturedcells.Wehypothesizethatspergen-1mightfunctionasanadhesivemoleculetoassemblemitochondriaintothemitochondrialsheatharoundtheouterdensefibersduringspermiogenesis.

【 授权许可】

Unknown