关键词: 结球甘蓝, AUX/IAA, 基因克隆, 表达分析

Abstract: To explore the function of AUX/IAA family genes on leaves and shoot tips development in cabbage, and screen the key AUX/IAA genes associated with leaves and shoot tips development, this study took cabbage line ‘519’  as material and though transcriptome comparative analysis screened 2 AUX/IAA genes expressed significantly different in shoot and leaves tips during heading and rosette stages, named BoIAA2 and BoIAA19, respectively. The cDNA sequences of BoIAA2 and BoIAA19 gene were obtained by PCR. Their CDS  length was 519 bp and 585 bp, and encoded 172, 194 amino acids, respectively. Further sequences discovered that the comparability of BoIAA2 and BoIAA19 with BrIAA2 and BnIAA19 were 99%, which contained the typical AUX/IAA DomainⅠ, Ⅱ, Ⅲ and Ⅳ. The RT-PCR analysis showed that the relative expression levels of BoIAA2 and BoIAA19 genes during heading stage were higher than rosette stage both in leaves and shoot tips, which was completely consistent with expression trend of their binding protein genes BoTIR1 and BoARF8, suggesting that BoIAA2 and BoIAA19 might regulate auxin signal transduction by combining backward genes BoTIR1 with BoARF8, and participate in leaves and shoot tips development regulation in cabbage.

Key words: Brassica oleracea L. var. capitata L., AUX/IAA, gene cloning, expression analysis