FUNCTION OF THE ter MUTATION AND MOLECULAR CHARACTERISTCS OF A NOVEL PRIMORDIAL GERM CELL GROWTH FACTOR (TERF) IN MICE

携带TER(畸胎瘤，Chr.)的同源小鼠18)导致雄性和雌性原始生殖细胞(PGC)缺陷的突变可作为先天性不育的动物模型。PGC缺乏症发生在含有+/+PGCs的重组胎儿睾丸和随后的胎儿睾丸体细胞。从+/+和+/ter胎儿睾丸体细胞获得的条件培养液(CM)中，与自身体细胞共培养的+/+PGCs数量增加，但在CM后数量减少。这些数据表明了一种新的与TER相关的生长因子TERF的可能性。本课题利用PGC培养系统和TER同源小鼠对TER基因的功能和TERF的分子特征进行了研究。所获得的结果如下1.在共培养的+/+胎儿支持细胞上，+/+和ter/ter PGCs均存活并增殖，但在ter/ter细胞上，它们的DNA合成发生了…。更正常的情况是。2.给予胎鼠卵巢和睾丸体细胞+/+CM可抑制+/+PGCs的凋亡，但不能抑制+/+PGCs的凋亡。两种CM均支持PGCs的DNA合成。3.给予+/+CM不能抑制与体细胞共培养的PGCs的凋亡。4.+/+CM含有热不稳定性和抗冻性类蛋白物质(M.W.&gt；30,000)支持生殖细胞存活，但不支持体细胞。T/T CM则没有。5.多种PGC生长因子及其受体在胚胎和成人睾丸及+/+睾丸中均有表达。6.由此得出结论：一种新型的TER相关PGC生长因子(称为TER因子，TERF)通过抑制PGC在发育过程中的凋亡来支持PGC的存活，其来源可能是卵巢和睾丸的体细胞。TER/TER体细胞产生一种缺省类型的TERF，导致TER/TER雄性和雌性正常存活、增殖和不育的TER/TerPGCs的凋亡性死亡。7.我们现在正在克隆TER基因。较少

Congenic mice bearing the ter (teratoma, Chr. 18) mutation that induces the deficiency of primordial germ cells (PGCs) in ter/ter males and females can serve as an animal model of congenital sterility. PGC deficiency occurs in the reconstituted fetal testes containing +/+ PGCs and ter/ter fetal testicular somatic cells. The number of +/+ PGCs that were co-cultured with own somatic cells in the conditioned media (CM) obtained from +/+ and +/ter fetal testicular somatic cells was increased but it was decreased in ter/ter CM. These data suggested a possibility of a novel ter-related growth factor, TERF. In this project the function of the ter gene and molecular characteristics of TERF were analyzed using PGC culture systems and the ter congenic mice. Results obtained were showed below.1. Both +/+ and ter/ter PGCs survived and proliferated on +/+ fetal Sertoli cells co-cultured, but those were degenerated by TUNEL-positive apoptosis on the ter/ter ones, whereas their DNA synthesis occurred … More normally. 2. Administration of +/+ CM from fetal ovarian and testicular somatic cells inhibited apoptosis in +/+ PGCs, but ter/ter CM did not. Both CM supported DNA synthesis of PGCs. 3. Administration of +/+ CM can not inhibit apoptosis in PGCs co-cultured with the ter/ter somatic cells. 4. +/+CM contained heat labile and freeze-resistant protein like substance (m.w. > 30,000) supporting survival of PGCs but not somatic cells. ter/ter CM did not. 5. Several PGC growth factors and their receptors were expressed in ter/terfetal and adult testes as well as in +/+ ones. 6. Thus, it is concluded that a novel ter-related PGC growth factor (designated as TER Factor, TERF) with soluble and membrane-bounded types supports PGC survival by inhibiting apoptosis in PGCs through develdpmental stages and that it is produced by ovarian and testicular somatic cells. It is also concluded that ter/ter somatic cells produce a default type of TERF, resulting in apoptotic death in ter/terPGCs with normal survivability and proliferation ability and sterility of ter/termales and females. 7. We are cloning of the genes in the ter locus now. Less