牛樟芝MYB转录因子的全基因组鉴定与分析

Genome-wide Identification and Analysis of MYB Transcription Factors of Antrodia cinnamomea

MYB转录因子在真菌的生长发育和胁迫响应中发挥多种作用。为了解牛樟芝MYB的功能,本研究利用本地BLAST对牛樟芝基因组进行比对分析,获得了9个牛樟芝MYB基因序列,并对牛樟芝MYB转录因子进行功能预测分析,利用转录组测序分析MYB基因在不同段木培养条件下子实体和菌丝体中的表达情况。蛋白理化性质分析发现,9个牛樟芝MYB转录因子多为不稳定蛋白,理论等电点介于4.92~8.51;亚细胞定位预测结果显示有1个转录因子(ACMYB1)定位在细胞质中,推测其可能参与细胞质基因的转录调控;有8个定位在细胞核中,占总蛋白的88.9%。二级结构预测发现以无规则卷曲和α-螺旋为主要结构,β-转角为次要结构。将9个牛樟芝MYB转录因子与5个已知功能的MYB蛋白共同构建系统进化树,14个MYB转录因子分为Ⅰ、Ⅱ两个分支,其中ACMYB1、ACMYB5与冬虫夏草中参与菌丝生长的MYB-6聚为一支,ACMYB9与冬虫夏草中参与子实体生长的MYB-3聚为一支,ACMYB6与顶头孢霉AcMYBA聚为一支。分析牛樟芝MYB转录因子在不同段木菌丝和子实体中的相对表达量,发现ACMYB1、ACMYB5、ACMYB6均在香樟段木菌丝体阶段高表达,推测其参与了牛樟芝菌丝体的生长,ACMYB9基因在香樟段木子实体阶段表达量上调,说明ACMYB9可能参与调控牛樟芝子实体的发育。本研究结果可为进一步挖掘研究牛樟芝MYB转录因子的功能奠定基础。

MYB transcription factors play a variety of roles in fungal growth and stress response.In order to understand the function of MYB,the local BLAST was used to perform comparative analysis on the Antrodia cinnamomea genome and 9 MYB gene sequences were obtained,and performed functional prediction analysis on the transcription factor of A.cinnamomea.Transcriptome sequencing was used to analyze the expression of MYB gene in the sporophore and mycelium under different basswood culture conditions.The results of physicochemical properties analysis showed that most of the 9 MYB transcription factors of A.cinnamomea were unstable proteins,and the theoretical isoelectric point ranged from 4.92 to 8.51.Subcellular localization revealed that 1 transcription factor was located in the cytoplasm(ACMYB1),which was speculated to be involved in the transcriptional regulation of cytoplasmic genes.8 transcription factors were located in the nucleus,accounting for 88.9%of the total protein.It was found that random coilα-helix were the main structuresβ-turn was the secondary structure.The phylogenetic tree was constructed by combining 9 MYB transcription factors and 5 MYB genes with known functions,14 MYB transcription factors are divided intoⅠ,Ⅱtwo branches,Among them,ACMYB1 and ACMYB5were clustered into a branch with MYB-6 which was involved in the growth of mycelia in Ophiocordyceps sinensis,ACMYB9 was clustered into a branch with MYB-3 which was involved in the growth of fruitbody in O.sinensis,and ACMYB6 was clustered into a branch with Ac MYBA in Acremonium chrysogenum.The relative expression levels of MYB transcription factor of A.cinnamomea in hyphae and fruiting body of different basswood were analyzed,it was found that ACMYB1,ACMYB5 and ACMYB6 were highly expressed in the mycelium stage of Cinnamomum camphora,it is speculated that they are involved in the growth of mycelium of A.cinnamomea,the expression of ACMYB9 gene was up-regulated in the fruitbody stage of C.camphora,these results suggested that ACMYB9 may be involved in regulating the fruiting body development of A.cinnamomea.The results of this study lay the foundation for further research on MYB transcription factor.