| Spermatogenesis, the fundamental function of adult testis, is a continuum of cellular differentiation in which three principal phases can be discerned: spermatogonia renewal and proliferation, meiosis and spermiogenesis. It is a complex process involving cell division, differentiation and interactions between cells in the microenvironment of the seminiferous tubule. Many specific genes and/or highly expressed in testis tissue are involved in the process of Spermatogenesis.The cloning of genes related Spermatogenesis and the study of their molecular regulating mechanism are very important for clinical diagnosis and treatment of male infertility. It is also important to male molecular contraception.In order to isolate genes differentially expressed in tissues, a variety of approaches for different display measurement have been developed and improved, such as suppressed subtractive hybridization (SSH), differential display reversed transcripted PCR (DDRT-PCR) and cDNA microarray technology. Compared with traditional hybridizing techniques, cDNA microarray has many advantages, such as its large scale, high throughout, high efficiency and its objectivity. It can be used as a genome-wide approach to functional characterization of large number of genes and their expression profiles. Advancement in technology of microarray construction and experimental strategy has resulted in expansion of many disease-associated, development-associated and special tissue-associated gene cloning and expression profile analysis.In order to clone genes associated with Spermatogenesis, we originally constructed cDNA microarray from the human testis large insert cDNA library. Insert cDNA was amplified from cDNA library and 9,216 individual clones were spotted on a nylon membrane. 8housekeeping genes and 2 plasmid DNAs were used as controls. Then mRNA was extracted respectively from fetus and adult testis, following reverse transcripted to cDNA probe incorporated with 33P-label dATP. The human testis cDNA microarray was hybridized with two probes respectively and the differently expressed clones were obtained. Those clones whose intensity was at least twofold difference were considered as differentially expressed genes in adult or fetal testis. The insert cDNA sequence was obtained by sequencing technology and BLAST with the gene database of GenBank.Among the positive cDNA clones that gave signals, 1522 clones had intensities at least twofold difference between fetus testis and adult testis: 1091 clones had intensities at least twofold higher for probe prepared from adult tissue than those from fetal tissue. Whereas 431 clones had at least twofold higher intensities for probe prepared from the fetal testis tissue than those from adult testis tissue. Those specifically expressed in fetal testis may be related to the development of human testis, whereas those specifically expressed in adult testis might be related to spermatogenesis. Among 1522 clones, sequencing and blast analysis identified 499 unique genes: 358 were found with their sequences reported before, 40 genes were new full length, remaining were 101 ESTs. To establish a functional profile of the 358 reported genes, proteins encoded by these genes were grouped into the following seven broad categories of biological roles: cell division, cell communication, cell structure/motility, organism defense, protein expression, metabolism and unclassified. Based on above results, we constructed expression map of genes related to the development of human testis and spermatogenesis. In this map, most genes were related to protein expression. To confirm above gene differential expression result from microarray hybridization, we relied on the real time PCR technique-TagMan assay to quantitateexpression of some genes in the fetus testis and adult testis respectively. 8 known genes were picked out and microarray hybridizing showed their highly expression in adult testis. Consistent with the microarray data, we measured at least a 3-fold higher level of mRNA for all eig...
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