Relationship of cysteine‐rich secretory protein‐3 gene and protein with semen quality in stallions

Abstract

Cysteine-rich secretory protein-3 (CRISP-3) and some of its nonsynonymous polymorphism have been related to the fertility and freezability of stallion semen; however, the role of the CRISP-3 gene and its seminal plasma protein in the raw semen quality is still unknown. The aim of this study was to evaluate the relationship of CRISP-3 with semen quality in stallions. DNA was obtained from blood samples of 100 stallions, from which 30 stallions were randomly selected to obtain 60 ejaculates. Through PCR amplification and sequencing, the variation of four nonsynonymous SNPs from CRISP-3 was identified and haplotypes were derived. Semen quality was assessed through the total motility (MOT), sperm vitality (SV), normal morphology (NM), functional integrity of membrane (MI) and a seminal quality index (SQi). CRISP-3 protein content of seminal plasma (SP) was determined by ELISA. The effect of the genotype, the haplotype and the concentration of the CRISP-3 protein on the seminal quality were evaluated through generalized linear models and linear regression analyses. Homozygous genotypes for SNP1, SNP2 and SNP3 and the heterozygous genotype for SNP4 showed a positive effect on seminal quality. Different haplotypes with positive effect on MOT, SV, NM, MI and SQi were identified. The allelic substitution analysis resulted in positive regression coefficients for MOT (SNP2) and MI (SNP2 and SNP3). A high level of CRISP-3 resulted in a higher MOT and SQi. It is concluded that the quality of stallion semen is influenced by the genotype of CRISP-3 and the concentration of CRISP-3 protein in SP.

Upregulation of CRISP‐3 and kallikrein in stallion seminal plasma is associated with poor tolerance of cooled storage

“…Based on genomic studies, CRISP‐3 is associated with stallion fertility and semen quality traits (Hamann et al, , Novak et al, , and Gottschalk, Metzger, Martinsson, Sieme, & Distl, ). In raw semen, high levels of CRISP‐3 in SP result in higher sperm motility and improved semen quality index (Restrepo, Rojano, & Usuga, ), but in our study, higher levels of CRISP‐3 decreased sperm longevity during storage.…”

“…Associations between this protein and semen quality traits are not necessarily direct and causal, but rather indirect correlations of androgen‐dependent traits. A possible role of CRISP‐3 in the regulation of oxidative pathways in semen has been proposed (Restrepo et al, ), based on the high content of cysteine residues in CRISP‐3 (Udby et al, ) and the contribution of these residues to oxidative reactions (Requejo, Hurd, Costa, & Murphy, ). In human semen, seminal vesicular fluid makes SP a zinc‐binding medium after ejaculation.…”

Effect of Seminal Plasma Protein Fractions on Stallion Sperm Cryopreservation

“…A negative association of Hep+ protein (HSP-1) with fertility was also found in horse seminal plasma [ 36 , 37 ]. On the other hand, the CRISP-3 protein, belonging to the Hep− fraction of stallion SP, is related to high semen freezability [ 32 , 37 ] and is a good marker of semen quality and fertility [ 36 , 38 ]. Moreover, it was suggested as a regulator of sperm elimination from the female reproductive tract [ 39 ].…”

Structural modelling of the equine protein disulphide isomerase A1 and its quantification in the epididymis and seminal plasma

“…Some epididymal proteins relate to equine fertility, such as HSP‐1 and HSP‐2, which are present in the sperm surface and play an important role in fecundation (Ekhlasi‐Hundrieser et al, ). Another example are the CRISP family members, located in the equatorial and post‐acrosomal region of the equine sperm head and midpiece and positively associated with sperm fusion by participating in binding to oocyte plasma membrane (Schambony, Gentzel, et al, ; Schambony, Hess, Gentzel, & Topfer‐Petersen, ) and seminal quality (Restrepo, Rojano, & Usuga, ).…”