Bettinger J C, Lee K, Rougvie A E
Department of Genetics and Cell Biology, University of Minnesota, St Paul 55108, USA.
Development. 1996 Aug;122(8):2517-27. doi: 10.1242/dev.122.8.2517.
The Caenorhabditis elegans gene lin-29 is required for the terminal differentiation of the lateral hypodermal seam cells during the larval-to-adult molt. We find that lin-29 protein accumulates in the nuclei of these cells, consistent with its predicted role as a zinc finger transcription factor. The earliest detectable LIN-29 accumulation in seam cell nuclei is during the last larval stage (L4), following the final seam cell division, which occurs during the L3-to-L4 molt. LIN-29 accumulates in all hypodermal nuclei during the L4 stage. The time of LIN-29 appearance in the hypodermis is controlled by the heterochronic gene pathway: LIN-29 accumulates in the hypodermis abnormally early, during the third larval stage, in loss-of-function lin-14, lin-28 and lin-42 mutants, and fails to accumulate in hypodermis of lin-4 mutants. LIN-29 also accumulates stage-specifically in the nuclei of a variety of non-hypodermal cells during development. Its accumulation is dependent upon the upstream heterochronic genes in some, but not all, of these non-hypodermal cells.
秀丽隐杆线虫基因lin-29在幼虫向成虫蜕皮过程中，对于侧皮下缝细胞的终末分化是必需的。我们发现lin-29蛋白在这些细胞的细胞核中积累，这与其作为锌指转录因子的预测作用一致。在缝细胞核中最早可检测到的LIN-29积累发生在最后一个幼虫阶段（L4），在L3至L4蜕皮期间最后一次缝细胞分裂之后。在L4阶段，LIN-29在所有皮下细胞核中积累。LIN-29在皮下出现的时间受异时性基因途径控制：在功能缺失的lin-14、lin-28和lin-42突变体中，LIN-29在第三幼虫阶段异常早期就在皮下积累，而在lin-4突变体的皮下则未能积累。在发育过程中，LIN-29也在多种非皮下细胞的细胞核中进行阶段特异性积累。在其中一些而非所有非皮下细胞中，其积累依赖于上游异时性基因。
