Sánchez-Herrero E, Guerrero I, Sampedro J, González-Reyes A
Centro de Biología Molecular Severo Ochod, Facultad de Ciencias, Universidad Autónoma de Madrid, Spain.
Mech Dev. 1994 Jun;46(3):153-67. doi: 10.1016/0925-4773(94)90068-x.
The abdominal-A (abd-A) gene of Drosophila specifies abdominal segments two through eight (A2-A8). We have found that the uniform expression of the abd-A protein under heat shock control transforms embryonic segments anterior to the abd-A domain into an abdominal segment of the A2-A6 type. Posterior abdominal segments and telson undergo little or no transformation, that is, the abd-A product is phenotypically suppressed posterior to its realm of expression. The comparison of wildtype embryos with embryos carrying the heat shock-abd-A construct but no abd-A endogenous product indicate that some elements of the pattern-like shape of denticle belts or ventral pits depend on the amount of abd-A protein. The concurrent expression of abd-A and other homeotic genes suggest competition for common downstream genes. This competition has been studied by looking at the expression on the visceral mesoderm of a gene downstream of abd-A, decapentaplegic, when two homeoproteins with opposing effects on its transcription are simultaneously induced.
果蝇的腹部-A（abd-A）基因决定了腹部第二至八节（A2-A8）。我们发现，在热休克控制下abd-A蛋白的均匀表达会将abd-A结构域前方的胚胎节段转化为A2-A6类型的腹部节段。腹部后部节段和尾节几乎没有或没有发生转化，也就是说，abd-A产物在其表达区域后方在表型上受到抑制。将野生型胚胎与携带热休克-abd-A构建体但没有内源性abd-A产物的胚胎进行比较表明，齿带或腹侧坑的一些类似模式形状的元素取决于abd-A蛋白的量。abd-A与其他同源异型基因的同时表达表明存在对共同下游基因的竞争。通过观察当对其转录具有相反作用的两种同源蛋白同时被诱导时，abd-A下游基因decapentaplegic在内脏中胚层上的表达，对这种竞争进行了研究。
