Furia M, Digilio F A, Artiaco D, D'Avino P P, Cavaliere D, Polito L C
Dipartimento di Genetica, Università di Napoli, Italy.
Chromosoma. 1991 Oct;101(1):49-54. doi: 10.1007/BF00360686.
The Pre-intermoult gene-1 (Pig-1) of Drosophila melanogaster maps on the X chromosome, at polytene bands 3C11-12, and is nested within the 79 kb intron of the dunce gene. Pig-1 has so far been characterized only preliminarily and its function is still unknown. We analysed the molecular organization of the gene by cDNA clone isolation and sequencing as well as S1 mapping and primer extension analyses. The results obtained reveal that the gene is colinear with its genomic sequence and define the usage of both 5' and 3' alternative sites for Pig-1 transcription; two continuous open reading frames (ORFs) are fully contained within the Pig-1 transcribed region, although several lines of evidence suggest that only the longer ORF is likely to be translated. We also report that the level of Pig-1 transcript is nearly fourfold reduced in a variant strain carrying a deletion within the Pig-1 upstream sequence, thus identifying a regulatory element required for high level gene expression.
黑腹果蝇的蜕皮前基因1（Pig-1）定位于X染色体的多线带3C11-12处，嵌套在笨蛋基因79 kb的内含子中。到目前为止，Pig-1仅得到初步表征，其功能仍然未知。我们通过cDNA克隆分离和测序以及S1作图和引物延伸分析来分析该基因的分子组织。获得的结果表明，该基因与其基因组序列共线性，并确定了Pig-1转录的5'和3'可变位点的使用情况；Pig-1转录区域内完全包含两个连续的开放阅读框（ORF），尽管有几条证据表明只有较长的ORF可能被翻译。我们还报告说，在Pig-1上游序列内携带缺失的变异菌株中，Pig-1转录本水平降低了近四倍，从而确定了高水平基因表达所需的调控元件。
