Isolation and identification of a novel motility-inhibiting factor from goat cauda sperm plasma membrane.
A motility inhibiting factor (MIF) in sperm plasma membrane of mammalian spermatozoa (goat) has been demonstrated. This factor has been purified to apparent homogeneity by Sepharose-6B affinity chromatography and DEAE-cellulose ion-exchange chromatography. The molecular weight of the isolated factor has been estimated as 98 kDa by molecular sieving and analytical HPLC. SDS-polyacrylamide gel electrophoresis of MIF gave a single band of 100 kDa, indicating that the factor is a monomer. MIF is a thermo-stable factor and it inhibited the spermatozoa motility in a dose dependent manner. It is a glycoprotein as it binds with high affinity to Sepharose-6B and the affinity matrix-bound factor can be eluted with D-galactose. Data show that the motility inhibiting activity is lost completely when treated with beta-galactosidase indicating that its sugar side chain is essential for its activity. Addition of MIF antibody caused significant enhancement of forward motility of the caput and cauda-spermatoza. This antibody may thus be useful for solving some of the problems of human infertility due to low sperm motility. The motility inhibiting protein may also be useful as a vaginal contraceptive.
Dungdung
S R
SR
Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Jadavpur, Kolkata-700032, India.
Majumder
G C
GC
D000818:Animals; D002462:Cell Membrane / Q000737:chemistry; D002848:Chromatography, DEAE-Cellulose; D004591:Electrophoresis, Polyacrylamide Gel; D004822:Epididymis; D006041:Goats; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology / Q000502:physiology*; D012661:Semen / Q000737:chemistry; D013081:Sperm Motility / Q000187:drug effects; D013094:Spermatozoa / Q000737:chemistry* / Q000187:drug effects / Q000502:physiology*
D008562:Membrane Glycoproteins