Cooper Trevor G, Wagenfeld Andrea, Cornwall Gail A, Hsia Nelson, Chu Sin Tak, Orgebin-Crist Marie-Claire, Drevet Joel, Vernet Patrick, Avram Cosmina, Nieschlag Eberhard, Yeung Ching-Hei
Institute of Reproductive Medicine of the University, D-48129 Münster, Germany.
Biol Reprod. 2003 Nov;69(5):1750-62. doi: 10.1095/biolreprod.103.017566. Epub 2003 Jul 30.
Transgenic male mice bearing inactive mutations of the receptor tyrosine kinase c-ros lack the initial segment of the epididymis and are infertile. Several techniques were applied to determine differences in gene expression in the epididymal caput of heterozygous fertile (HET) and infertile homozygous knockout (KO) males that may explain the infertility. Complementary DNA arrays, gene chips, Northern and Western blots, and immunohistochemistry indicated that some proteins were downregulated, including the initial segment/proximal caput-specific genes c-ros, cystatin-related epididymal-spermatogenic (CRES), and lipocalin mouse epididymal protein 17 (MEP17), whereas other caput-enriched genes (glutathione peroxidase 5, a disintegrin and metalloproteinase [ADAM7], bone morphogenetic proteins 7 and 8a, A-raf, CCAAT/enhancer binding protein beta, PEA3) were unchanged. Genes normally absent from the initial segment (gamma-glutamyltranspeptidase, prostaglandin D2 synthetase, alkaline phosphatase) were expressed in the undifferentiated proximal caput of the KO. More distally, lipocalin 2 (24p3), CRISP1 (formerly MEP7), PEBP (MEP9), and mE-RABP (MEP10) were unchanged in expression. Immunohistochemistry and Western blots confirmed the absence of CRES in epididymal tissue and fluid and the continued presence of CRES in spermatozoa of the KO mouse. The glutamate transporters EAAC1 (EAAT3) and EAAT5 were downregulated and upregulated, respectively. The genes of over 70 transporters, channels, and pores were detected in the caput epididymidis, but in the KO, only three were downregulated and six upregulated. The changes in these genes could affect sperm function by modifying the composition of epididymal fluid and explain the infertility of the KO males. These genes may be targets for a posttesticular contraceptive.
携带受体酪氨酸激酶c-ros无活性突变的转基因雄性小鼠缺乏附睾起始段，并且不育。应用了几种技术来确定杂合可育（HET）和不育纯合敲除（KO）雄性小鼠附睾头中基因表达的差异，这些差异可能解释不育的原因。互补DNA阵列、基因芯片、Northern和Western印迹以及免疫组织化学表明，一些蛋白质表达下调，包括起始段/近端附睾头特异性基因c-ros、胱抑素相关附睾生精蛋白（CRES）和脂质运载蛋白小鼠附睾蛋白17（MEP17），而其他附睾头富集基因（谷胱甘肽过氧化物酶5、解整合素和金属蛋白酶[ADAM7]、骨形态发生蛋白7和8a、A-raf、CCAAT/增强子结合蛋白β、PEA3）表达未改变。起始段通常不存在的基因（γ-谷氨酰转肽酶、前列腺素D2合成酶、碱性磷酸酶）在KO小鼠未分化的近端附睾头中表达。在更远端，脂质运载蛋白2（24p3）、CRISP1（以前称为MEP7）、PEBP（MEP9）和mE-RABP（MEP10）的表达未改变。免疫组织化学和Western印迹证实附睾组织和液中不存在CRES，而KO小鼠精子中持续存在CRES。谷氨酸转运体EAAC1（EAAT3）和EAAT5分别下调和上调。在附睾头中检测到70多种转运体、通道和孔的基因，但在KO小鼠中，只有3种下调，6种上调。这些基因的变化可能通过改变附睾液的成分影响精子功能，并解释KO雄性小鼠的不育。这些基因可能是睾丸后避孕的靶点。
