烟草ACS基因家族鉴定及二氯喹啉酸胁迫条件下的表达分析

二氯喹啉酸药害给烟叶生产造成较大影响。为明确烟草二氯喹啉酸药害的发生机制，对1-氨基环丙烷-1-羧酸合酶(1-aminocyclopropane-1-carboxylate synthase，ACS)基因家族进行了鉴定，并对二氯喹啉酸胁迫条件下的基因表达模式进行分析。结果表明，普通烟草共有26个ACS基因。染色体定位分析显示，23个ACS基因定位在染色体上，3个定位在scaffold上。亚细胞定位分析显示，ACS主要定位于细胞核或细胞质中。进化分析表明，ACS蛋白进化形成3个类别。序列比对显示，ACS氨基酸序列含有家族保守结构域和活性位点。启动子分析发现，ACS基因启动子区含有脱落酸、茉莉酸、水杨酸、生长素和赤霉素5种激素反应共10种类型的顺式作用元件。表达分析显示，大部分ACS家族成员均受二氯喹啉酸诱导而上调表达。 

Identification of tobacco ACS gene family and its expression analysis under quinclorac stress

Quinclorac use causes significant losses in tobacco production. In order to clarify the mechanism of quinclorac phytotoxicity to tobacco, the ACS (1-aminocyclopropane-1-carboxylate synthase) family was identified and its expression pattern under quinclorac stress was analyzed. The results showed that there were 26 ACS genes in Nicotiana tabacum. The chromosomal location analysis suggested that 23 ACS genes were located on the chromosomes, and the other 3 genes were located on the scaffold. The subcellular localization prediction indicated that ACS genes were mainly localized in the nucleus or cytoplasm. Phylogenetic analysis showed ACS evolved into three types. The sequence alignment showed that amino acid sequences of ACS family contained conserved motifs and active sites. Cis-acting elements analysis revealed that NtACS genes contained 10 cis-acting elements, including abscisic acid, jasmonic acid, salicylic acid, auxin and gibberellin. Expression pattern analysis revealed that most ACS genes were up-regulated by quinclorac stress.