Siegfried E, Perkins L A, Capaci T M, Perrimon N
Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115.
Nature. 1990 Jun 28;345(6278):825-9. doi: 10.1038/345825a0.
The metameric pattern of the Drosophila embryo is regulated by a combination of maternal and zygotic genes. The segment-polarity class of genes are required for the correct patterning within each segmental unit. Mutations in any one of these genes results in deletions and duplications of parts of each segment. The segment-polarity genes act coordinately by means of local cellular interactions to assign and maintain an identity for each cell in the segment, and to establish segment boundaries. Here we describe the molecular characterization of a novel segment-polarity gene, zeste-white3 (zw3). Embryos derived from germ lines that are homozygous for zw3 mutations (zw3 embryos) have phenotypes similar to embryos that are mutant for the segment-polarity gene naked (nkd). These embryos lack most of the ventral denticles, which are differentiated structures derived from the most anterior region of each segment. We have isolated the zw3 gene and compared the structure of one maternal and one zygotic transcript encoded by the gene. The zw3 gene is unique among the segment-polarity genes so far characterized, in that it encodes proteins that have homology to serine-threonine protein kinases. This indicates that zw3 may play a part in a signal transduction pathway involved in the establishment of cell identity within each embryonic segment.
果蝇胚胎的体节模式受母体基因和合子基因共同调控。基因的体节极性类别对于每个节段单元内的正确模式形成是必需的。这些基因中任何一个发生突变都会导致每个节段部分的缺失和重复。体节极性基因通过局部细胞间相互作用协同作用，为节段中的每个细胞赋予并维持一种身份，并建立节段边界。在此，我们描述了一个新的体节极性基因——小体白色3（zw3）的分子特征。来自zw3突变纯合种系的胚胎（zw3胚胎）具有与体节极性基因裸（nkd）突变胚胎相似的表型。这些胚胎缺乏大部分腹侧齿，腹侧齿是源自每个节段最前部区域的分化结构。我们分离出了zw3基因，并比较了该基因编码的一个母体转录本和一个合子转录本的结构。zw3基因在目前已鉴定的体节极性基因中是独特的，因为它编码与丝氨酸 - 苏氨酸蛋白激酶具有同源性的蛋白质。这表明zw3可能在参与每个胚胎节段内细胞身份确立的信号转导途径中发挥作用。
