Robinson L L, Gaskell T L, Saunders P T, Anderson R A
MRC Human Reproductive Sciences Unit, Centre for Reproductive Biology, 37 Chalmers Street, Edinburgh EH3 9ET, UK.
Mol Hum Reprod. 2001 Sep;7(9):845-52. doi: 10.1093/molehr/7.9.845.
The proto-oncogene receptor, c-kit, and its ligand have been demonstrated to be essential to the processes of germ cell migration, proliferation and survival in the rodent. The aim of the present study was to investigate the expression of c-kit mRNA and protein in human fetal ovary and testis across the gestational period 13-21 weeks. In the ovary, this crucial period of development spans the transition from oogonial replication by mitosis to primordial follicle formation. In the testis, germ cells (gonocytes) are mitotically active. Expression of c-kit mRNA was demonstrated by reverse transcription-polymerase chain reaction (RT-PCR) in both ovary and testis at all gestational ages examined. Testicular germ cell specific expression of c-kit mRNA was confirmed by RT-PCR using specific cell types recovered by laser capture microscopy. The expression of c-kit protein by both male and female germ cells was demonstrated by immunohistochemistry at all gestational ages examined, and was confirmed by immunoblotting. In both, c-kit was localized to the cell membrane except in oocytes within primordial follicles where it was localized to the cytoplasm. These data demonstrate that the expression of c-kit mRNA and protein is germ cell specific in human fetal gonads and are consistent with an important role for the c-kit/kit ligand signalling system in germ cell proliferation and survival in the developing human gonad.
原癌基因受体c-kit及其配体已被证明对啮齿动物生殖细胞的迁移、增殖和存活过程至关重要。本研究的目的是调查c-kit mRNA和蛋白在孕13至21周的人胎儿卵巢和睾丸中的表达情况。在卵巢中，这一关键的发育阶段涵盖了从通过有丝分裂进行卵原细胞复制到原始卵泡形成的转变。在睾丸中，生殖细胞（生殖母细胞）有活跃的有丝分裂。在所检测的所有孕龄的卵巢和睾丸中，通过逆转录聚合酶链反应（RT-PCR）证明了c-kit mRNA的表达。使用通过激光捕获显微镜回收的特定细胞类型，通过RT-PCR证实了c-kit mRNA在睾丸生殖细胞中的特异性表达。在所检测的所有孕龄，通过免疫组织化学证明了雄性和雌性生殖细胞中c-kit蛋白的表达，并通过免疫印迹得到证实。在两者中，c-kit定位于细胞膜，除了原始卵泡内的卵母细胞，在那里它定位于细胞质。这些数据表明，c-kit mRNA和蛋白的表达在人胎儿性腺中是生殖细胞特异性的，并且与c-kit/kit配体信号系统在发育中的人性腺生殖细胞增殖和存活中的重要作用一致。
