Gigliotti S, Graziani F, De Ponti L, Rafti F, Manzi A, Lavorgna G, Gargiulo G, Malva C
Istituto Internazionale di Genetica e Biofisica, CNR, Università di Napoli, Italy.
Dev Genet. 1989;10(1):33-41. doi: 10.1002/dvg.1020100106.
This study isolated cDNA clones from egg-chamber and adult female Drosophila cDNA libraries using as probe a DNA fragment from a 200-kb "chromosome walk" in region 32E of the second chromosome of D. melanogaster. The present authors believe that these clones correspond to a new vitelline membrane protein (VMP) gene because 1) cDNA clones in Northern blots identify a transcript expressed in a tissue- and stage-specific manner: stage 10 egg-chambers; 2) the sequence of cDNAs and of the genomic subclone shows homology with the other VMP genes that have been identified to date; 3) the amino acid composition of the translational product has the high content of proline and alanine characteristic of VMPs. Two aspects emerging from this study are worth stressing: 1) the presence of a hydrophobic domain that is highly conserved in all the VMP genes; and 2) the particularly narrow period of expression of the isolated gene, which could be related to the mechanism of vitelline membrane assembly.
本研究使用来自黑腹果蝇第二条染色体32E区域一个200 kb“染色体步移”的DNA片段作为探针，从卵室和成年雌性果蝇cDNA文库中分离出cDNA克隆。本文作者认为这些克隆对应一个新的卵黄膜蛋白（VMP）基因，原因如下：1）Northern印迹中的cDNA克隆鉴定出一种以组织和阶段特异性方式表达的转录本：10期卵室；2）cDNA和基因组亚克隆的序列与迄今已鉴定的其他VMP基因显示出同源性；3）翻译产物的氨基酸组成具有VMP特有的高脯氨酸和丙氨酸含量。这项研究中出现的两个方面值得强调：1）在所有VMP基因中高度保守的疏水结构域的存在；2）分离基因特别狭窄的表达时期，这可能与卵黄膜组装机制有关。
