Sarkar P, Sengupta D, Basu S, Maitra U
Gene. 1985;33(3):351-5. doi: 10.1016/0378-1119(85)90243-4.
The entire nucleotide sequence of a 409-bp HincII fragment, located within the MboI-E fragment on bacteriophage T3 DNA and containing a major class-III T3 RNA polymerase promoter positioned at 98% on the standard T3 genetic map, has been determined. Alignment of this class-III promoter with previously determined T3 RNA polymerase promoters, with start points of transcription (+1) in register, indicates high degree of sequence conservation between position -16 to +6 among all T3 RNA polymerase promoters. The conserved portion of the (-) strand sequence is 5'-A-TA-T-AT-A-C-C-C-T-C-A-C-T-A-A-A-G-G-G-A---3'. This fragment also contains an open reading frame (ORF) with a translational start codon located at position +146 which is preceded by a potential ribosome binding site (RBS). There is more than 70% amino acid-sequence homology between the deduced sequences of the -NH2 terminal region of this putative T3 phage protein and the corresponding protein coded by bacteriophage T7 (protein of T7 gene 19.5).
已确定位于噬菌体T3 DNA的MboI-E片段内的一个409 bp HincII片段的完整核苷酸序列，该片段包含一个位于标准T3遗传图谱98%位置的主要III类T3 RNA聚合酶启动子。将该III类启动子与先前确定的T3 RNA聚合酶启动子进行比对，转录起始点（+1）对齐，结果表明所有T3 RNA聚合酶启动子在-16至+6位置之间具有高度的序列保守性。（-）链序列的保守部分为5'-A-TA-T-AT-A-C-C-C-T-C-A-C-T-A-A-A-G-G-G-A---3'。该片段还包含一个开放阅读框（ORF），其翻译起始密码子位于+146位置，在此之前有一个潜在的核糖体结合位点（RBS）。该推定的T3噬菌体蛋白的-NH2末端区域的推导序列与噬菌体T7编码的相应蛋白（T7基因19.5的蛋白）之间的氨基酸序列同源性超过70%。
