Watanabe T, Kankel D R
Department of Biology, Yale University, New Haven, Connecticut 06511-8112.
Genetics. 1990 Dec;126(4):1033-44. doi: 10.1093/genetics/126.4.1033.
Previous genetic studies have shown that wild-type function of the l(1)ogre (lethal (1) optic ganglion reduced) locus is essential for the generation and/or maintenance of the postembryonic neuroblasts including those from which the optic lobe is descended. In the present study molecular isolation and characterization of the l(1)ogre locus was carried out to study the structure and expression of this gene in order to gain information about the nature of l(1)ogre function and its relevance to the development of the central nervous system. About 70 kilobases (kb) of genomic DNA were isolated that spanned the region where l(1)ogre was known to reside. Southern analysis of a l(1)ogre mutation and subsequent P element-mediated DNA transformation mapped the l(1)ogre+ function within a genomic fragment of 12.5 kb. Northern analyses showed that a 2.9-kb message transcribed from this 12.5-kb region represented l(1)ogre. A 2.15-kb portion of a corresponding cDNA clone was sequenced. An open reading frame (ORF) of 1,086 base paris was found, and a protein sequence of 362 amino acids with one highly hydrophobic segment was deduced from conceptual translation of this ORF.
先前的遗传学研究表明，l(1)ogre（致死(1)视叶神经节减少）基因座的野生型功能对于胚胎后神经母细胞的产生和/或维持至关重要，这些神经母细胞包括视叶起源的神经母细胞。在本研究中，对l(1)ogre基因座进行了分子分离和表征，以研究该基因的结构和表达，从而获取有关l(1)ogre功能的性质及其与中枢神经系统发育相关性的信息。分离出了约70千碱基（kb）的基因组DNA，其跨度为已知l(1)ogre所在的区域。对l(1)ogre突变进行Southern分析，随后进行P因子介导的DNA转化，将l(1)ogre+功能定位在一个12.5 kb的基因组片段内。Northern分析表明，从这个12.5 kb区域转录的一个2.9 kb的信使RNA代表l(1)ogre。对一个相应的cDNA克隆的2.15 kb部分进行了测序。发现了一个1086个碱基对的开放阅读框（ORF），并从该ORF的概念翻译中推导出一个含有一个高度疏水片段的362个氨基酸的蛋白质序列。
