Proteomic comparison of detergent-extracted sperm proteins from bulls with different fertility indexes

Abstract

Intrinsic factors such as proteins modulate the fertilising ability of male gametes. We compared detergent-extracted sperm protein composition of bulls with different fertility indexes in order to highlight putative fertility markers of sperm. Frozen semen from 23 Holstein bulls with documented fertility was used. According to their 'fertility solution' (SOL), as calculated by the Canadian dairy network, bulls were divided into four groups: high fertility (HF) (SOLO3.0; nZ6), medium-HF (2.9OSOLO2.0; nZ5), medium-low fertility (K2.8OSOLOK4.9; nZ8) and low fertility (LF; SOL!K5.0; nZ4), with a SOLZ0 being the average. Triton X-100 protein extracts from ejaculated spermatozoa were subjected to two-dimensional difference gel electrophoresis, and polypeptide maps were quantitatively analysed by ImageMaster software. Nine protein spots showed significant differences between the HF and LF groups, and eight of these proteins were identified by liquid chromatography-tandem mass spectrometry. T-complex protein 1 subunits 3 and q (CCT5 and CCT8), two isoforms of epididymal sperm-binding protein E12 (ELSPBP1), proteasome subunit a type-6 and binder of sperm 1 (BSP1) were more expressed in the LF group than in the HF group. On the other hand, adenylate kinase isoenzyme 1 (AK1) and phosphatidylethanolamine-binding protein 1 (PEBP1) were more expressed in the HF group than in the LF group. The presence and expression level of ELSPBP1, BSP1, AK1 and PEBP1 were confirmed by western blot. A linear regression model established that CCT5 and AK1 explained 64% (P!0.001) of the fertility scores. The reported functions of these proteins are in agreement with a putative involvement in defective sperm physiology, where lower or higher levels can jeopardise sperm ability to reach and fertilise the oocyte.

Protein biomarkers for male artificial insemination subfertility in bovine spermatozoa

“…In another proteomic analysis, adenylate kinase isoenzyme 1 (AK1) and phosphatidylethanolamine‐binding protein 1 (PEBP1) were detected abundantly in the spermatozoa from the bulls (Holstein) with higher AI fertility rates 38. In contrast, the T‐complex protein 1 subunits ε and θ (CCT5 and CCT8), epididymal sperm‐binding protein E12 (ELSPBP1), proteasome subunit α type‐6, and binder of sperm 1 (BSP1) were predominately abundant in the spermatozoa from the bulls with lower AI fertility rates.…”

Gelatin Binding Proteins in Reproductive Physiology

“…ELSPBP1 was characterized as a sperm binding protein, expressed in the epididymis and containing the highest number of the four fn2 domains in comparison to other GBPs [22,23]. ELSPBP1 has been also described as HE12 in humans and CE12 in dogs [23,24].…”

“…ELSPBP1 has been also described as HE12 in humans and CE12 in dogs [23,24]. Furthermore ELSPBP1 orthologs have been recognized in equine, porcine and bovine systems [25] while no DNA homologs of ELSPBP1 were observed in either the rat or mouse [25].…”

“…The study of ELSPBP1 expression in the bull epididymis utilizing a specific antibody has revealed an association with its role in maintaining spermatozoa cell volume during sperm maturation [26]. More recently, ELSPBP1 has been observed to be more prominent in extracts of spermatozoa in sub fertile bulls and has been exclusively identified in dead spermatozoa [23,27]. Furthermore, it was investigated that the epididymis secretes ELSPBP1 complexed with an epididymosome, which transports ELSPBP1 to dead spermatozoa in the presence of zinc [24,27].…”

Avaliações seminais e novas ferramentas genômicas na estimação da fertilidade em touros

“…Touros classificados como de alta e baixa fertilidade apresentaram diferente perfil de proteí-nas do plasma seminal (bpss) [87]- [88]. Killian [88] identificou alta e positiva correlação entre fertilidade e bsp 30kd, fosfolipase a2 e osteopontina, enquanto touros com baixa fertilidade tiveram alta concentração de espermadesina Z13.…”