Wojcik E, Murphy A M, Fares H, Dang-Vu K, Tsubota S I
Department of Biology, University of Michigan, Ann Arbor 48109.
Genetics. 1994 Dec;138(4):1163-70. doi: 10.1093/genetics/138.4.1163.
A hybrid dysgenesis-induced mutation, enhancer of rudimentaryp1 (e(r)p1), is a recessive enhancer of a weak rudimentary mutant phenotype in Drosophila melanogaster. The e(r) gene was cloned using P element tagging and localized to region 8B on the X chromosome. It encodes a 1.0-kb and a 1.2-kb transcript. The 1.0-kb transcript is present in both adult males and females, while the 1.2-kb transcript is predominantly found in females. The difference in the lengths of the two e(r) transcripts is caused by two different polyadenylation sites spaced 228 bp apart. The amounts of both of these transcripts are drastically reduced in the e(r)p1 mutant. The P element in e(r)p1 is inserted in the 5'-untranslated leader region near the start of transcription. It may be producing its effect by suppressing transcription and/or by providing transcription termination and polyadenylation signals. The putative e(r) protein is 104 amino acids in length and bears no striking resemblance to protein sequences in GenBank or PIR. While its biochemical function is unknown at this time, sequence analysis indicates that the e(r) protein is highly conserved and, presumably, functionally very important. The amino acid sequences of the D. melanogaster and the Drosophila virilis proteins are 95% identical.
一种杂种发育不全诱导的突变，即残基增强子p1（e(r)p1），是黑腹果蝇中一种弱残基突变体表型的隐性增强子。通过P因子标签克隆了e(r)基因，并将其定位到X染色体的8B区域。它编码一个1.0 kb和一个1.2 kb的转录本。1.0 kb的转录本在成年雄性和雌性中都存在，而1.2 kb的转录本主要在雌性中发现。这两种e(r)转录本长度的差异是由两个相距228 bp的不同聚腺苷酸化位点引起的。在e(r)p1突变体中，这两种转录本的量都大幅减少。e(r)p1中的P因子插入到转录起始附近的5'非翻译前导区域。它可能通过抑制转录和/或通过提供转录终止和聚腺苷酸化信号来产生其效应。推测的e(r)蛋白长度为104个氨基酸，与GenBank或PIR中的蛋白质序列没有明显相似性。虽然目前其生化功能尚不清楚，但序列分析表明e(r)蛋白高度保守，可能在功能上非常重要。黑腹果蝇和果蝇的蛋白质氨基酸序列有95%的同一性。
