Molecular mechanism of epididymal protease inhibitor modulating the liquafication of human semen

Molecular mechanism of epididymal protease inhibitor modulating the liquafication of human

semen

Zengjun Wang;Wei Zhang;Hongfei Wu;Yuangeng Xu

【期刊名称】《生物医学研究杂志（英文版）》 【年(卷),期】2007(021)001

【摘要】Objective: To study the molecular mechanism of epididymal protease

inhibitor

(Eppin)

modulating

the

liquafication

of

semen.Methods: Human semenogelin cDNA (nucleotides 82-849) and Eppin cDNA (nucleotides 70-423) were generated by PCR and cloned into pET-100D/TOPO.Recombinant Eppin and Sg were produced by BL21 (DE3). The association of Eppin with Sg was studied by far-western and radioautography.In vitro the digestion of Sg by PSA in the presence or absence of recombinant Eppin was studied. The effect of anti-Q20E (N-terminal) and C-terminal of Eppin on Eppin-Sg binding was monitored. Results: Eppin binds Sg on the surface of human spermatozoa with C-terminal Eppin (aa75-133).Recombinant Sg was digested with PSA ,many low molecular weight fragments were produced, when Eppin is bound to Sg,then digested by PSA , producing incomplete digestion and a 14.5-14.8 kDa fragmen. Antibody binding to the N-terminal of Eppin did not affect Sg digestion. Addition of antibodies to the C-terminal of Eppin inhibited the modulating effects