Insights into structure-function correlations of ungulate seminal plasma proteins.
The seminal plasmas of a variety of mammalian species contain factors that prevent inappropriate acrosome reactions ("decapacitating factors") and proteins that upon binding to the sperm surface enhance the fertilising potential of spermatozoa. The emerging view is that the membrane remodelling events that underlie capacitation of ejaculated spermatozoa in the female's genital tract is essentially conserved though it can be accomplished by different seminal plasma proteins in different species. The major seminal plasma proteins of ungulates (i.e., pig, bull, ram, stallion) belong to the spermadhesin family and to the Fn2-choline-binding proteins. Although the final effect of different seminal plasmas on homologous sperm capacitation may represent an example of functional convergence, individual proteins from the same family appear to function in a species-specific manner. Thus, differences in their structures, relative abundance, and expression patterns along the male genital tract may determine species-specific effects on sperm physiology of homologous proteins. Discussed here are a plethora of biochemical and biophysical studies on seminal plasma proteins from ungulates, including the determination of the crystal structures of porcine and bovine spermadhesins and bull PDC-109, which have provided over the past two decades insights into the molecular and structural basis of their role along the fertilisation process.
Calvete
Juan J
JJ
Instituto de Biomedicina de Valencia (CSIC), Jaime Roig 11, 46010-Valencia, Spain. jcalvete@ibv.csic.es
Sanz
Libia
L
D000818:Animals; D002417:Cattle; D005260:Female; D006736:Horses; D008297:Male; D008322:Mammals / Q000502:physiology*; D017434:Protein Structure, Tertiary; D029589:Seminal Plasma Proteins / Q000737:chemistry / Q000502:physiology*; D012756:Sheep; D013045:Species Specificity; D013075:Sperm Capacitation / Q000502:physiology*; D013084:Sperm-Ovum Interactions / Q000502:physiology; D013329:Structure-Activity Relationship; D013552:Swine
D029589:Seminal Plasma Proteins