【摘要】 NAC家族转录因子NST1 (NAC SECONDARY WALL THICKENING PROMOTING FACTOR 1)和SND1 (SECONDARY WALL-ASSOCIATED NAC DOMAIN 1)在调控植物次生细胞壁发育和木质素合成方面发挥着重要作用,然而NST1和SND1在菜心木质化或者发育过程中的表达特性和功能尚不明确。本研究以拟南芥AtNST1和AtSND1蛋白的氨基酸序列为参考,从菜心中鉴定到了二者的同源物,分别命名为BcNST1和BcSND1。生物信息学分析显示, BcNST1和BcSND1分别与AtNST1和AtSND1具有较高的氨基酸序列一致性和相似性,并且它们的亲缘关系较近。BcNST1和BcSND1蛋白均定于细胞核中,同时还具备转录激活活性。基因表达模式分析发现BcNST1和BcSND1基因在菜心角果中的表达水平最高,其次是薹茎,并且二者在薹茎中的表达水平随着束间纤维细胞次生细胞壁的发育而增高。上述的研究结果为进一步探究BcNST1和BcSND1调控菜心木质化的分子机理提供了前期研究基础。更多还原

【Abstract】 The NAC transcriptional regulators NST1(SECONDARY WALL THICKENING PROMOTING FACTOR 1) and SND1(SECONDARY WALL-ASSOCIATED NAC DOMAIN 1), play pivotal roles in directing secondary cell wall and lignin biosynthesis. However, the expression characteristics and functions of NST1and SND1 during lignification or development in Chinese flowering cabbage(Brassica campestris ssp.chinensis var. utilis) are not yet clear. This article revealed two Arabidopsis NST orthologs identified in Chinese flowering cabbage, designated as BcNST1 and BcSND1. Bioinformatics analysis showed that BcNST1 and BcSND1 had high amino acid sequence consistency and similarity with AtNST1 and AtSND1,respectively, and their genetic relationships were relatively close. Remarkably, both BcNST1 and BcSND1proteins demonstrated transcriptional activation functions and are predominantly localized in the nucleus.It was evident that stems and fruit tissues of Chinese flowering cabbage express BcNST1 and BcSND1 at elevated levels compared to root, leaf and flower tissues. Interestingly, the transcript abundance of BcNST1 and BcSND1 steadily magnified during interfascicular fibroblast’s secondary cell wall maturation stages. The above results provide a preliminary research basis for further exploring the molecular mechanism of BcNST1 and BcSND1 regulating lignification in Chinese flowering cabbage.更多还原