Analysis Of Mechanisms Of Testicular Toxicity Using DNA Microarray Technology

镉是一种已知的雄性生殖毒物，睾丸中基因表达模式的变化被用于：1）鉴定对毒物的初级和次级基因反应，2）鉴定睾丸中毒物的初始靶细胞，3）使用基因表达变化的时间模式来确定毒性机制。 一种小鼠睾丸微阵列已被开发出来，并正在用于镉的研究。 它也将是有用的基因敲除，内分泌操纵和其他治疗的影响的研究。 用从小鼠睾丸和不同发育阶段分离的生殖细胞的mRNA构建的8个cDNA文库从5'端进行单程测序，以鉴定用于此目的的克隆。 对28，000多个克隆进行了测序，并将22，000多个EST存入公共数据库。 利用该序列信息和公共数据库中的其他信息构建了小鼠睾丸22K基因芯片。 通过比较使用睾丸微阵列和全小鼠基因组微阵列获得的信息，已经确定，在镉处理后，睾丸微阵列上的基因数量明显多于在全小鼠基因组微阵列上的基因数量。

Changes in patterns of gene expression in the testis in response to cadmium, a known male reproductive toxicant are being used to: 1) identify primary and secondary gene responses to the toxicant, 2) to identify the initial target cell of the toxicant in the testis, and 3) to use the temporal pattern of changes in gene expression to define the mechanisms of toxicity. A mouse testis microarray has been developed and is being used in the cadmium studies. It also will be useful for studies of effects of gene knockouts, endocrine manipulations, and other treatments. Eight cDNA libraries constructed with mRNA from mouse testis and germ cells isolated at different stages of development were subjected to single-pass sequencing from the 5' end to identify clones to be used for this purpose. Over 28,000 clones were sequenced and over 22,000 ESTs were deposited in public databases. A mouse testis 22K microarray has been constructed using this sequence information and other information public databases. A comparison of the information gained from using the testis microarray and a whole mouse genome microarray has determined that a substantially larger number of genes on the testis microarray are seen to undergo changes in expression following cadmium treatment than are seen on the whole mouse genome microarray.