MOLECULAR BIOLOGY OF THE MALE ENHANCED ANTIGEN GENES

男性增强抗原MEA的基因是用 抗H-Y抗原的抗血清，或经血清学检测 男性(SDM)抗原，来自原核表达的cDNA文库 小白鼠的睾丸。分子分析显示，中东和非洲股票 相当相似的特征归因于血清学 H-Y抗原，被认为是后者的候选基因。 MEA在遗传上是保守的，显示出男性增强的 在已建立的雄性细胞系Sertoli细胞中表达，14日龄 小鼠胚胎，以及早熟和成熟的哺乳动物睾丸。 另外两个基因，基因A和B，与MEA基因在 人类和小鼠的基因组，并且表达类似于MEA。 这个基因簇位于人类6号染色体和小鼠身上 17号染色体.遗传保护和男性增强 表达表明MEA基因簇的产物是 哺乳动物精子发生和/或睾丸中的重要因素- 决心。 我们的长期目标是定义功能和 MEA基因簇的生物学作用机制。我们 计划分离全长cdna和基因组序列 这个基因簇，并确定了它们的DNA序列，推断 蛋白质和启动子结构。我们将研究分子 通过鉴定其组织特异性来调节其表达 启动子，顺式作用增强剂，反式作用调节因子， 以及与其转录相关的染色质改变 不同生精阶段的活性。我们将综合 利用基因工程方法提高MEA的单特异性 针对这些蛋白质的抗体。我们计划用这些抗体 分离天然分子并研究组织特异性 在小鼠胚胎发育过程中的表达。我们特别是 对鉴定表达这些基因的细胞类型感兴趣 在性腺发生过程中。我们将进一步研究它们的可能性 利用体外分离的性腺细胞在睾丸组织中的作用 在存在或不存在纯化的MEA的情况下的再结合分析 以及相关的蛋白质。转基因小鼠将被构建成 表达可调控的港湾诱导型MEA基因 使用外部刺激剂。建议的研究结果将会 提供有关性行为机制的有价值的信息 哺乳动物的功能障碍和生精功能障碍，并可 与人类的临床表现有关。

The gene for the male-enhanced antigen, MEA, was isolated with an antiserum against the H-Y antigen, or serologically detected male (SDM) antigen, from a prokaryotic expression cDNA library of the mouse testis. Molecular analyses revealed that MEA shares considerable similar characteristics attributed to the serological H-Y antigen, and is considered as a candidate gene for the latter. The MEA is genetically conserved and shows a male-enhanced expression in established male cell lines, Sertoli cells, 14-day mouse embryo, and premature and mature mammalian testes. Two other genes, Gene A and B, are linked to the MEA gene in both human and mouse genomes, and express similarly as MEA. This gene cluster is located in human chromosome 6 and mouse chromosome 17. The genetic conservation and male-enhanced expression suggest that the products from MEA gene cluster are important factors in mammalian spermatogenesis and/or testis- determination. Our long term goals are to define the functions and the mechanisms of biological actions to the MEA gene cluster. We plan to isolate both full-length cDNA and genomic sequences for this gene cluster, and determine their DNA sequences, deduced proteins, and promoter structures. We will study the molecular regulation of their expression by identifying their tissue-specific promoters, cis-acting enhancers, trans-acting regulatory factors, and the chromatin alteration associated with their transcriptional activity at different spermatogenic stages. We will synthesize the MEA by genetic engineering methods and raise mono-specific antibodies against these proteins. We plan to use these antibodies to isolate the native molecules and to study the tissue-specific expression during mouse fetal development. We are particularly interested in identifying the cell types expressing these genes during gonadogenesis. We will further examine their possible roles in testis organization using in vitro gonadal cell dissociation- reassociation assays in the presence or absence of purified MEA and related proteins. Transgenic mice will be constructed to harbor inducible MEA genes whose expression can be modulated with external stimulants. Result from the proposed studies will provide valuable information concerning the mechanisms of sexual dysfunctions and spermatogenic failure in mammals, and can be related to clinical manifestations in man.