Sundaresan N R, Saxena V K, Sastry K V H, Anish D, Marcus Leo M D, Kantaraja C, Saxena M, Ahmed K A
Disease Genetics and Biotechnology Laboratory, Central Avian Research Institute, Izatnagar, 243122 Bareilly, India.
Vet Res Commun. 2008 Jan;32(1):13-9. doi: 10.1007/s11259-007-9005-y. Epub 2007 Jun 13.
Chicken postovulatory follicle (POF) regression occurs via the process of apoptosis. However, the signals and initiator pathways responsible for regression of the POF are unknown. In the current study, we examined gene expression patterns of various caspases (caspase-1, -2 and -3) involved in apoptosis by semi-quantitative RT-PCR. The percentage of apoptotic cells during POF regression was also quantified by flow cytometry. Expression of caspase-3 mRNA was noted in the largest preovulatory follicle (F1). However, the initiator caspases (caspase-1 and -2) were not expressed in F1. During the regression of the POF, caspase-3 was activated during initial stages, whereas the initiator caspases were upregulated at the later stages (POF4 and POF5). The percentage of apoptotic cells was significantly higher during the regression of the POF. It might be possible that levels of caspase-3 mRNA do not necessarily reflect the cell's potential for facilitating apoptosis, as activation of the caspase-3 by initiator caspases is required for its function. We presume that both caspase-1 and caspase-2 were key initiators in the regression of chicken POF and that the apoptosis-mediated regression of POFs might be similar to mammalian corpus luteum involution.
鸡排卵后卵泡（POF）的退化是通过细胞凋亡过程发生的。然而，负责POF退化的信号和起始途径尚不清楚。在本研究中，我们通过半定量逆转录聚合酶链反应（RT-PCR）检测了参与细胞凋亡的各种半胱天冬酶（半胱天冬酶-1、-2和-3）的基因表达模式。还通过流式细胞术对POF退化过程中凋亡细胞的百分比进行了定量。在最大的排卵前卵泡（F1）中发现了半胱天冬酶-3 mRNA的表达。然而，起始半胱天冬酶（半胱天冬酶-1和-2）在F1中未表达。在POF退化过程中，半胱天冬酶-3在初始阶段被激活，而起始半胱天冬酶在后期阶段（POF4和POF5）上调。POF退化过程中凋亡细胞的百分比显著更高。半胱天冬酶-3 mRNA的水平不一定反映细胞促进凋亡的潜力，因为其功能需要起始半胱天冬酶激活半胱天冬酶-3。我们推测半胱天冬酶-1和半胱天冬酶-2都是鸡POF退化的关键起始因子，并且POF的凋亡介导的退化可能与哺乳动物黄体退化相似。
