单细胞蓝藻集胞藻6803 R2中藻蓝蛋白操纵子的复制

Duplication of the phycocyanin operon in the unicellular cyanobacterium Anacystis nidulans R2.

作者信息

Lau R H, Blakeley S D, Alvarado-Urbina G, Bailly J E, Condie J A, Lau P C

机构信息

Department of Botany, University of Toronto, Ontario, Canada.

出版信息

Gene. 1989 Aug 15;80(2):375-80. doi: 10.1016/0378-1119(89)90302-8.

DOI:10.1016/0378-1119(89)90302-8

PMID:2511077

Abstract

Two phycocyanin (PC) operons, each containing alpha- and beta-subunit genes, have been isolated from the unicellular cyanobacterium Anacystis nidulans R2. Using oligodeoxyribonucleotide probes for the PC-coding regions, three PstI fragments were obtained and shown to contain the two operons, which are 2.7 kb apart, with a proposed gene order of 5'-(beta I-alpha I)-(beta II-alpha II)-3'. The nucleotide sequences of both alpha-subunit genes are identical, as are the beta-sequences and the 51-bp intergenic regions. However, significant nucleotide sequence differences are found in both the 5' and 3' untranslated regions of the two operons. Two mRNA species of 1.65 and 1.5 kb were detected in A. nidulans R2 RNA when probed with either the alpha-specific or the beta-specific probe. The results demonstrate the existence of two PC operons which are both transcriptionally active.

摘要

已从单细胞蓝藻集胞藻6803（Anacystis nidulans R2）中分离出两个藻蓝蛋白（PC）操纵子，每个操纵子都包含α亚基基因和β亚基基因。使用针对PC编码区的寡脱氧核糖核苷酸探针，获得了三个PstI片段，这些片段被证明包含两个操纵子，它们相距2.7 kb，推测的基因顺序为5'-（βI-αI）-（βII-αII）-3'。两个α亚基基因的核苷酸序列相同，β序列和51 bp的基因间隔区也相同。然而，在两个操纵子的5'和3'非翻译区都发现了显著的核苷酸序列差异。当用α特异性或β特异性探针进行检测时，在集胞藻6803的RNA中检测到了1.65 kb和1.5 kb的两种mRNA。结果表明存在两个转录活性均较高的PC操纵子。