Affolter M, Montagne J, Walldorf U, Groppe J, Kloter U, LaRosa M, Gehring W J
Department of Cell Biology, Biozentrum, University of Basel, Switzerland.
Development. 1994 Apr;120(4):743-53. doi: 10.1242/dev.120.4.743.
The Drosophila homolog of the vertebrate serum response factor (SRF) was isolated by low stringency hybridization. Nucleotide sequence analysis revealed that the Drosophila SRF homolog (DSRF) codes for a protein that displays 93% sequence identity with human SRF in the MADS domain, the region required for DNA binding, dimerization and interaction with accessory factors. The DSRF gene is expressed during several phases of embryonic development. In the egg, both the RNA and the protein are maternal in origin and slowly decrease in amount during gastrulation. After germ band retraction, high levels of zygotic expression are observed in a distinct subset of peripheral tracheal cells distributed throughout the embryo. Many of these cells are at the tip of tracheal branches and are in direct contact with the target tissues. The DSRF gene was mapped to position 60C on the second chromosome, and overlapping deficiencies which remove the gene were identified. Analysis of tracheal development in embryos carrying these deletions revealed a degeneration of most of the major branches of the tracheal system. Although the initial migration of tracheal cells was not affected in those deficient embryos, many tracheal cells appeared not to maintain their correct position and continued to migrate. Thus, the DSRF gene might play a role in the proper formation and maintenance of the trachea.
通过低严谨度杂交分离出了脊椎动物血清反应因子（SRF）的果蝇同源物。核苷酸序列分析表明，果蝇SRF同源物（DSRF）编码一种蛋白质，该蛋白质在MADS结构域与人类SRF具有93%的序列同一性，MADS结构域是DNA结合、二聚化以及与辅助因子相互作用所必需的区域。DSRF基因在胚胎发育的几个阶段都有表达。在卵中，RNA和蛋白质均源自母体，在原肠胚形成期间数量缓慢减少。胚带回缩后，在遍布胚胎的外周气管细胞的一个特定子集中观察到高水平的合子表达。这些细胞中的许多位于气管分支的末端，并且与靶组织直接接触。DSRF基因被定位到第二条染色体上的60C位置，并鉴定出了缺失该基因的重叠缺失。对携带这些缺失的胚胎中的气管发育进行分析发现，气管系统的大多数主要分支发生退化。尽管在那些缺陷胚胎中气管细胞的初始迁移未受影响，但许多气管细胞似乎无法维持其正确位置并继续迁移。因此，DSRF基因可能在气管的正常形成和维持中发挥作用。
