Protamine 3 expressions in crossbred bull spermatozoa may not be a prognostic marker for differentiating good and poor quality semen

Protamines are short and highly basic sperm-specific nuclear proteins. Though the expression profile of protamines 1 and 2 is well known, but there is little knowledge of protamine 3 expression in bovine semen. In this study, Frieswal (HF x Sahiwal) crossbred bulls were categorized into two groups (good and poor quality) based on the initial progressive motility of semen and other seminal parameters. The mRNA expression of PRM3 gene among two groups was evaluated by real time quantitative polymerase chain reaction (PCR) using TaqMan chemistry, where peptidylprolyl isomerase A (PPIA) was used as an internal control. Our finding revealed that expression of PRM3 was down regulated in poor quality semen producers as compared to good quality semen producing group, but unfortunately no significant difference of transcript abundance was observed between the groups. To shed light on present findings, it can thus assume that PRM3 may not be a prognostic marker to differentiate good and poor quality bull semen in Frieswal cattle. Keywords: Protamine 3, Frieswal, semen, expression African Journal of Bioitechnoloy , Vol 13(19), 1999-2003