Alfonzo J D, Sahota A, Deeley M C, Ranjekar P, Taylor M W
Department of Biology, Indiana University, Bloomington 47405, USA.
Gene. 1995 Aug 8;161(1):81-5. doi: 10.1016/0378-1119(95)00239-3.
We have cloned, sequenced and characterized the APT1 (adenine phosphoribosyltransferase) gene from Saccharomyces cerevisiae. The APT1 sequence includes an open reading frame encoding 221 amino acids and is contained within a 1322-bp insert that complements APRT-deficient mutants to wild-type levels of enzyme activity. Analysis by primer extension revealed multiple transcription start points (tsp) and a major tsp 21-bp upstream from the ATG start codon. A transcript initiated at the major tsp would yield a 700-nt mRNA which is in agreement with the size observed by Northern analysis. Sequence comparison indicates that the yeast enzyme shares strong similarities with other known APRT of bacterial, invertebrate, plant and mammalian origins.
我们已经从酿酒酵母中克隆、测序并鉴定了APT1（腺嘌呤磷酸核糖转移酶）基因。APT1序列包含一个编码221个氨基酸的开放阅读框，位于一个1322碱基对的插入片段中，该片段可将APRT缺陷型突变体的酶活性恢复到野生型水平。引物延伸分析揭示了多个转录起始点（tsp），其中一个主要的tsp位于ATG起始密码子上游21个碱基处。从主要tsp起始的转录本将产生一个700个核苷酸的mRNA，这与Northern分析观察到的大小一致。序列比较表明，酵母中的这种酶与其他已知的来源于细菌、无脊椎动物、植物和哺乳动物的APRT有很强的相似性。
