柳叶蜡梅PAL基因家族的鉴定及表达分析

Identification and Expression Patterns of PAL Gene Family in Chimonanthus salicifolius

苯丙氨酸解氨酶(PAL)是苯丙烷代谢的关键限速酶,在调节植物胁迫应答和生长发育方面发挥重要作用。为明确PAL基因家族在柳叶蜡梅生长发育中的功能,本研究系统分析了PAL基因家族成员的理化特征、顺式作用元件、系统发育树、保守基序、染色体定位及共线性关系,并比较了它们在不同组织、叶和花不同时期及不同激素处理下的表达模式。结果显示,7个柳叶蜡梅CsPAL家族基因锚定于5条染色体上,编码413~768个氨基酸,分为2个亚族,与腊梅CpPAL蛋白亲缘关系较近,存在基因复制现象。CsPAL家族基因启动子区域富集大量激素响应与胁迫应答的顺式元件。CsPAL家族基因在柳叶蜡梅不同组织、叶和花不同生长阶段及ABA、MeJA处理下呈现差异表达,CsPAL6在叶中高表达,受ABA、MeJA诱导,与黄酮物质在叶和花不同时期的减少相一致,推测可能与黄酮物质的合成有关。研究结果为将来研究CsPAL基因家族在黄酮生物合成中的功能提供了理论参考。

Phenylalanine ammonia-lyase(PAL)is a critical rate-limiting enzyme in phenylpropane metabolism,which plays an essential role in plant growth and stress response.To investigate the role of the PAL gene family in the growth and development of Chimonanthus salicifolius,physicochemical properties,cis-acting elements,conserved motifs,phylogenetic tree,chromosomal localization,and collinearity relationship were systematically investigated in this study.The expression patterns in different tissues,at various growth stages of leaves and flowers,and under the treatment of abscisic acid(ABA)and methyl jasmonate(MeJA)were compared.The results showed that 7 PAL family genes were located on 5 chromosomes,encoding proteins with 413-768 amino acids.They were classified into 2 subfamilies,showing close relationships with CpPAL proteins,and exhibited gene tandem duplications.A large number of cis-acting elements containing hormone responses and stress responses were enriched in the promoter regions of CsPAL family genes.The CsPAL family genes were differentially expressed in different tissues,at different developmental stages of leaves and flowers,and under the treatment of ABA and MeJA.CsPAL6 was highly expressed in leaves,and induced by ABA and MeJA,which was associated with the reduction of flavonoids,suggesting that CsPAL6 might be involved in the biosynthesis of flavonoids.The results provide a theoretical reference for further study the role of CsPAL gene family genes in the biosynthesis of C.salicifolius flavonoids.