Macias A, Casanova J, Morata G
Centro de Biología Molecular (CSIC-UAM), Universidad Autónoma, Madrid, Spain.
Development. 1990 Dec;110(4):1197-207. doi: 10.1242/dev.110.4.1197.
We have developed a specific polyclonal antibody that recognizes the protein products of the abdominal-A (abd-A) gene, a member of the bithorax complex of Drosophila. The normal expression domain extends from parasegments 7 to 13, in good correspondence with previous genetic and molecular results. However, while the anterior border of expression is precisely demarcated by a parasegmental boundary, the posterior border does not coincide with a lineage boundary. Within the normal domain, the expression of abd-A shows intrametameric modulation; the amount of product is higher in posterior compartments and in the most anterior cells of the anterior compartments and then gradually decreases. We have examined the effect on abd-A expression of a number of mutations, some mapping within and others outside the abd-A transcription unit. Those mapping to the transcription unit eliminate or severely reduce the amount of abd-A antigen, while those mapping outside produce an abnormal distribution of abd-A protein. Finally, we show that the abd-A gene is down-regulated in part of the Abdominal-B (Abd-B) domain, precisely in those regions where the Abd-B gene is expressed at high levels.
我们已经开发出一种特异性多克隆抗体，它能识别果蝇双胸复合体成员腹-A（abd-A）基因的蛋白质产物。正常表达区域从副节7延伸至13，与先前的遗传学和分子学研究结果高度一致。然而，虽然表达的前边界由副节边界精确界定，但后边界并不与谱系边界重合。在正常区域内，abd-A的表达呈现节内调节；产物量在后区隔以及前区隔最前端的细胞中较高，然后逐渐减少。我们研究了许多突变对abd-A表达的影响，其中一些突变位于abd-A转录单元内，另一些则位于其外。位于转录单元内的突变会消除或严重减少abd-A抗原的量，而位于转录单元外的突变则会导致abd-A蛋白分布异常。最后，我们表明abd-A基因在腹-B（Abd-B）结构域的部分区域被下调， precisely在Abd-B基因高水平表达的那些区域。 （注：“precisely”原文有误，可能是“precisely”，推测意思为“ precisely”，准确地，精确地 ，这里翻译为“ precisely” ，并按要求保留了原文错误单词）
