Luo H, Perlin M H
Department of Biology, University of Louisville, KY 40292.
Gene. 1993 Dec 31;137(2):187-94. doi: 10.1016/0378-1119(93)90005-n.
The gene (gamma-tub) encoding gamma-tubulin (gamma-Tub) was isolated from a cosmid library constructed for Ustilago violacea by using a PCR-amplified DNA fragment as a probe. About 2.8 kb of DNA sequence was analyzed and found to encode a protein of 469 amino acids highly homologous to the gamma-Tub from other organisms. There were eight introns interrupting the coding sequence. A 'TATA'-like sequence was found 389 bp upstream from the initial Met codon. No polyadenylation signal was found in the 3' non-coding region. Southern blot analyses indicated that gamma-tub is a single-copy gene. Northern blot analyses indicated that a 1.81-kb RNA species was transcribed. Primer extension experiments determined that the transcription start point (tsp) is at 58 bp downstream from the putative TATA box, with another possible tsp at 95 bp downstream. The long 5' non-coding sequence of the RNA contained several small open reading frames; their possible roles in the regulation of gamma-tub translation are discussed.
通过使用PCR扩增的DNA片段作为探针，从为紫黑粉菌构建的粘粒文库中分离出编码γ-微管蛋白（γ-Tub）的基因（gamma-tub）。分析了约2.8 kb的DNA序列，发现其编码一个由469个氨基酸组成的蛋白质，该蛋白质与其他生物的γ-微管蛋白高度同源。有8个内含子中断编码序列。在起始甲硫氨酸密码子上游389 bp处发现了一个类似“TATA”的序列。在3'非编码区未发现多聚腺苷酸化信号。Southern印迹分析表明gamma-tub是单拷贝基因。Northern印迹分析表明转录出了一个1.81 kb的RNA分子。引物延伸实验确定转录起始点（tsp）位于假定的TATA框下游58 bp处，另一个可能的tsp位于下游95 bp处。RNA的长5'非编码序列包含几个小的开放阅读框；讨论了它们在γ-tub翻译调控中的可能作用。
