中文摘要：

lin-4是控制Caenorhabditis elegans（C．elegans）幼虫发育的异时性基因，也是一种小RNA分子（microRNA）。通过整体原位杂交检测小RNA lin-4在野生型和lin-14、lin-28突变体中的区域性表达，探讨lin．4在C．elegans发育时空控制中的作用。结果表明：lin-4mRNA在胚胎发育的早期和中期表达，胚胎后期至L1期末没有表达，之后又持续表达，成虫中也可以检测到砌．4mRNA的存在。在lin-14和lin-28突变体中，lin-4的表达基本与野生型一致，不受lin-14．lin-28基因突变的影响，说明lin-14和lin-28是lin-4的下游基因。

英文摘要：

lin-4 is an important heterochronic gene as well as a microRNA which plays an crucial role in regulating the larval stage transition in Caenorhabditis elegans （C.elegans）. To determine the function of lin-4 in the temporal and spatial development of C.elegans, we analyzed the expression of lin-4 mRNA in wild type and mutants of lin-14 and lin-28 via in situ hybridization. The results showed that lin-4 mRNA presented in the early embryos of wild type, and could not detected in the later embryos or L1 larvae. The level of it continued to increase through L2 to adult worms. During subsequent stages of development, it presented in the epidermis, and also in the germiline of adult worms. In lin-14 and lin-28 mutants, the expression of lin-4 mRNA pattern was same as wild type which implied lin-14 and lin-28 was the down streamed gene of lin-4.