Benson Andrew, Steed Josh, Malloy Mia, Davis Adam J
Department of Poultry Science, University of Georgia, Athens, GA 30602, USA.
Animals (Basel). 2022 Jun 29;12(13):1672. doi: 10.3390/ani12131672.
The avian inner perivitelline layer (IPVL), containing the zona pellucida (ZP) family of proteins, surrounds the ovulated ovum. In mammalian species, ZP proteins serve as key component(s) in binding sperm and initiating the acrosome reaction. Sperm binding at the germinal disc (GD) region of the IPVL initiates fertilization in avian species, and the amount of sperm binding at the GD reflects female fertility. The current research determined whether reported differences in mRNA expression in two genetic lines of turkey hens (E, high fertility and F, low fertility) translated to the protein level. ZPB2 in the IPVL is greater in the GD region compared with the nongerminal disc (NGD) region, as indicated by both mRNA and protein expression. However, protein expressions of ZPB1 and ZPC in the IPVL of E- and F-line turkey hens was in contrast to previously reported mRNA expression. The results indicate that the mRNA expression of ZP proteins at their site of synthesis in E- and F-line hens often does not directly correlate with the IPVL abundance of these proteins. The greater protein concentration of ZPB2 in the GD region compared with the NGD regions suggests that this protein may be critical for sperm binding at the GD region.
禽卵黄膜内层（IPVL）包裹着排卵后的卵子，其中含有透明带（ZP）蛋白家族。在哺乳动物中，ZP蛋白是结合精子并引发顶体反应的关键成分。精子在IPVL的胚盘（GD）区域结合引发禽类受精，且GD处精子结合量反映了雌性的生育能力。当前研究确定了火鸡母鸡两个遗传品系（E系，高生育力；F系，低生育力）中报道的mRNA表达差异是否转化为了蛋白质水平。如mRNA和蛋白质表达所示，IPVL中的ZPB2在GD区域比非胚盘（NGD）区域更多。然而，E系和F系火鸡母鸡IPVL中ZPB1和ZPC的蛋白质表达与先前报道的mRNA表达相反。结果表明，E系和F系母鸡中ZP蛋白在其合成位点的mRNA表达通常与这些蛋白在IPVL中的丰度不直接相关。与NGD区域相比，GD区域中ZPB2的蛋白质浓度更高，这表明该蛋白可能对精子在GD区域的结合至关重要。
