ABSTRACT
Background: follicle stimulating hormone [FSH] plays an essential role in reproductive physiology and follicular development
Objective: a new variant of the equine fsh [efsh] gene was cloned, sequenced, and expressed in Pichia pastoris [P. pastoris] GS115 yeast expression system
Materials and Methods: the full-length cDNAs of the efsh[alpha] and efsh[beta] chains were amplified by reverse transcription polymerase chain reaction [RT-PCR] using the total RNA isolated from an Iranian Turkmen-thoroughbred horse's anterior pituitary gland. The amplified efsh chains were cloned into the pPIC9 vector and transferred into P. pastoris. The secretion of recombined eFSH using P. pastoris expression system was confirmed by Western blotting and immunoprecipitation [IP] methods
Results: the DNA sequence of the efsh[beta] chain accession number JX861871, predicted two putative differential nucleotide arrays, both of which are located in the 3?UTR. Western blotting showed a molecular mass of 13 and 18 kDa for eFSH[alpha] and eFSH[beta] subunits, respectively. The expression of desired protein was confirmed by protein G immunoprecipitation kit
Conclusions: eFSH successfully expressed in P. pastoris. These findings lay a foundation to improve ovulation and embryo recovery rates as well as the efficiency of total embryo-transfer process in mares