小苍兰ACC合成酶FhACS1基因的克隆与序列分析

以小苍兰品种“上农金皇后”为研究对象，利用PCR技术和染色体步移技术首次克隆到了ACC合成酶FhACS1基因的全长序列和编码序列。结果表明：FhACS1基因全长为2 576 bp，包含长为433 bp的5′端非编码区序列（5′-UTR）以及长为373 bp的3′端非编码区序列（3′-UTR）；开放读码框（ORF）长度为1 371 bp，推定编码457个氨基酸。分析表明，该基因包含3个内含子和4个外显子。序列分析结果显示，FhACS1推导蛋白具备ACS蛋白的7个保守结构域；在氨基酸水平上，FhACS1与小果芭蕉的同源性最高（85%）；系统进化分析表明，FhACS1与孟宗竹BaACS（BAC56949.1）、水稻OsACS1（AAA33888.1）、小果芭蕉MaACS1（AAQ13435）的亲缘关系最近。在其已知启动子区域，发现有多个对脱落酸、赤霉素、细胞分裂素等激素响应的顺式元件，以及对干旱和低温等逆境胁迫响应的顺式元件。

Cloning and Characterization of ACC Synthase FhACS1 Gene from Fressia

The full-length DNA and coding DNA sequence (CDS) of a new 1-aminocyclopropane-1-carboxylate synthase FhACS1 gene was cloned from Fressia hybrida ‘Shangnong Jinhuanghou’ for the first time. DNA sequence of FhACS1 was 2 576 bp long including 433 bp of 5′-UTR and 373 bp of 3′-UTR. Start codon and stop codon located at 434 and 2 201 nt, respectively. This gene contained 3 introns and 4 exons. The full length of CDS is 1 371 bp, encoding a 51.2 kDa protein with 457 amino acid residues. The results showed that FhACS1 contained seven conserved domains of ACS proteins, which was highly homologous to ACS of Musa acuminata with amino acid sequence homology of 85%. Phylogenetic analysis showed that FhACS1 gene in Fressia was closely related to BaACS(BAC56949.1) in bamboo, OsACS1(AAA33888.1) in rice, and MaACS1(AAQ13435) in banana. Several putative cis-elements responding to phytohormones(ABA, GA and CTK) and stress (dehydration and cold) in FhACS1 were predicted using online promoter analysis software.