Analysis of sd sequence of cry id showed that it was obviously different from that of other cry genes published 分析cry1d基因的sd序列,發(fā)現(xiàn)與已報道的其它cry基因的sd序列不同。
The pa7 fragment was sequenced and several motifs similar to prokaryotic promoter elements such as - lobox , - 35box and up box were found . the sd sequence which was bound by ribosome and atg site were also found . the pat fragment was blast in genebank , but there is no its " homological sequence 對pa7片段的序列分析發(fā)現(xiàn)其距5 ’端931bp ? 1091bp處具有原核生物典型基因啟動子的保守結(jié)構(gòu)- 10區(qū)和- 35區(qū),以及翻譯必需的sd序列和翻譯起始位點等。
After site - mutation using pcr was introduced into cryld sd sequence ( gggga - ggagg ) , cryld - lacz expressed higher 1 . 0 - 1 . 6 times than before mutation , suggesting that ggagg might be most effective sd sequence for bacillus thuringiensis , meanwhile , low translational initiation efficiency caused by improper sd sequence might lead to low expression of cryld in hd133 利用pcr定點誘變技術(shù)突變其sd序列gggga為ggagg后, cry1d - lacz融合基因的表達提高了1 . 0 - 1 . 6倍。表明ggagg同樣是蘇云金芽胞桿菌最有效的sd序列,同時也揭示了基因cry1d表達量低的原因之一是不合適的sd序列而導(dǎo)致較低的翻譯起始效率。