An oocytic membrane receptor for biotin‐binding protein

FEBS Letters

White, Harold B.²  Vieira, Amandio V.³  Vieira, Päivi M.¹ 

[1] Department of Molecular Genetics, University of Vienna, Dr. Bohrgasse 9/2, A-1030 Vienna, Austria;Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA;Department of Biochemistry, University of Alberta, Edmonton, Alta, T6G 2S2, Canada

关键词: Chicken;    Biotin-binding protein;    Estrogen;    Oocyte membrane receptor;    BBP;    biotin-binding protein;    DTT;    dithiothreitol;    TCA;    trichloroacetic acid;    SDS-PAGE;    sodium dodecyl sulfatepolyacrylamide gel electrophoresis;   

DOI  :  10.1016/0014-5793(96)00169-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The chicken oocyte accumulates a biotin-binding protein (BBP) in the yolk that is distinct from the avidin in the ‘egg white’. An identical BBP to that of yolk is also present in the circulation of the laying hen. We report the first evidence for the existence of a BBP receptor in the oocyte vitelline membrane. Reduction of the 100 kDa receptor results in loss of BBP-binding activity; this suggests that a disulfide-bonded region of the receptor is necessary for maintaining BBP-binding activity. We show further that the levels of serum BBP are strictly dependent on the presence of estrogen. As expected, BBP is not detected in significant quantities in rooster serum. Thus, these results suggest that circulatory BBP, like other estrogen-dependent components of serum, has a cognate binding activity on the oocyte membrane that may mediate its endocytosis.

【 授权许可】

Unknown