Serpins are a superfamily of related protease inhibitors with common structural features and inhibitory mechanisms. However, SERPINA 14 in mammals does not have inhibitory activity against most known proteases. Rather, it may have an immunoregulatory role in mammals to prevent rejection of the fetal allograft by inhibiting lymphocyte proliferation and natural killer cell function. In the pig, SERPINA14 is involved in iron transport to the fetus by binding to and stabilizing the iron-binding protein uteroferrin (ACP5). In chickens, these very little known about serpins in chickens. Therefore, we investigated the expression patterns of serpin genes in the oviduct of adult hens and in the oviduct of 37-day-old chicks treated with an estrogen analogue, diethylstilbestrol (DES). Results indicated that SERPINB3 and SERPINB11 genes were highly expressed in oviducts of DES-treated chicks, but not in oviducts of control chicks. Both SERPINB3 and SERPINB11 transcripts were localized specifically to the gland-like areas of oviducts of DES-treated chicks. Immunohistochemical analyses confirmed that SERPINB3 and SERPINB11 proteins were present in the gland-like area and luminal epithelium of the oviducts of DES-treated chicks. Collectively, the results suggest that SERPINB3 and SERPINB11 are expressed in response to estrogens and they have distinct functions related to development and differentiation of the mature oviduct in hens.

S-adenosylhomocysteine hydrolase-like protein 1 (AHCYL1), also known as IP3 receptor- binding protein released with IP3 (IRBIT), is a member of the AHCY-like protein family. AHCYL1 protein regulates IP3-induced Ca2+ release in the cytoplasm of cells and, therefore, is likely to be an important gene regulating various biological processes in the oviduct of chickens. Inmammals, expression is greatest during activation of dendritic cells which are antigen presenting cells associated with immunoregulatory processes in blood and skin. However, the identification of the AHCYL1 gene in chickens has not been investigated. In the present study, we first used RT-PCR to demonstrate AHCYL1 gene expression in adult chicken organs and oviducts of immature chickens treated with DES (diethylstilbesterol, a synthetic estrogen agonist). The results indicated that AHCYL1 mRNA is expressed in chicken reproductive organs (testis, ovary and oviduct). Inaddition, expression of AHCYL1 mRNA increased in response to DES-treated immature oviducts compared to the non-treated control immature oviducts of chickens. Interestingly, AHCYL1 was abundant in the cytoplasm of luminal and glandular epithelia, but not in other cell-types such as stroma and connective tissues, of the chicken oviduct. These results suggest that AHCYL1 is a novel estrogen-stimulated gene associated with development of the chicken oviduct, as well as functions of oviductal glandular and luminal epithelia that may include activation of resident immune cells, such as dendritic cells.