Marja-liisa Hendriks Purification of a Candidate Gonadotropin Surge-inhibiting/attenuating Factor (gnsif/af) Showing Mapk as a Possible Target
نویسندگان
چکیده
Gonadotropin surge-inhibiting/attenuating factor (GnSIF/AF) has been known for over two decades, but its molecular structure has not been completely characterized yet. In the last 20 years, five different putative GnSIF/AF sequences have been published. In this article, we describe a procedure to isolate and characterize GnSIF/AF from bovine follicular fluid. A GnSIF/ AF-derived synthetic peptide (SP-GnSIF/AF) was produced, and the intracellular bioactivity of GnSIF/AF was tested for intracellular action with a MAPK-assay. Two different bioactive molecular weight forms of GnSIF/AF were isolated, a 160-kDa heteromeric and a monomeric 40-kDa protein. The 40-kDa form appeared to be a subunit of the 160-kDa protein. The synthetic peptide mimicked the actions of GnSIF/AF, such as inhibition of GnRH-induced LH secretion and attenuation of the MAPK phosphorylation. The two GnSIF/AF candidates do not show similarities with previously published GnSIF/AF sequences. These are the first data showing the influence of GnSIF/AF on intracellular processes involved in GnRH self-priming and that the biological action of GnSIF/AF was preserved for the produced synthetic peptide. The results provide strong evidence that the identified candidate proteins are the true GnSIF/AF. A new candidate GnSIF/AF protein with bioactivity
منابع مشابه
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