Molecular characterization and expression profile of uterine serpin (SERPINA14) during different reproductive phases in water buffalo (Bubalus bubalis)

Uterine serpins (SERPINA14) play important roles during pregnancy in the farm animals. In this study, we have cloned and characterized cDNA sequence encoding the bubaline SERPINA14. We also studied its spatio-temporal expression in the uterine endometrium. The bubaline SERPINA14 has an open reading frame of 1299 bp. Itshares ∼90% identity with the SERPINA14 of other ruminant livestock species. Phylogenetically, bubaline SERPINA14 has been placed in the same clade that contained other mammalian homologues with a maximum identity to bovine SERPINA14. Using an anti-ovine monoclonal antibody, Western blot analysis of the uterine fluid of buffalo during the early stage of pregnancy confirmed the presence of SERPINA14 of about 48,000 Da. The results of quantitative real time PCR (RT-qPCR) as well as in situ hybridization demonstrated a stage and tissue specific expression of bubaline SERPINA14. The level of SERPINA14 mRNA was low during stage I (Days 3–5), which increased (P < 0.05) during stage II (Days 6–15) and then subsequently declined during stage III (Days 16–21) of the estrus cycle. During early pregnancy (Days ∼30 of gestation) the level of SERPINA14 mRNA was as high as that during stage II of the estrus cycle. The SERPINA14 mRNA was localized in the glandular epithelium. The differential spatio-temporal expression of SERPINA14 in the uterine endometrium of buffalo suggests its plausible important roles in reproduction.