阳桃木质素生物合成相关基因的筛选与分析  

Identification and Analysis Lignin Biosynthesis Genes of Averrhoa carambola

作　　者：赵亚梅 陈生煜 游乐 韩茹 翟俊文[1] 任惠[2] 吴沙沙[1] ZHAO Ya-mei;CHEN Sheng-yu;YOU Le;HAN Ru;ZHAI Jun-wen;REN Hui;WU Sha-sha(College ofLandscape Architecture,Fujian Agriculture and Forestry University/Key Laboratory of National Forestry and Grassland Administration far Orchid Conservation and Utilization,Fuzhou 350002;Horticulture Research Insistute of Guangxi Academy of Agricultural Science,Nanning 530007)

机构地区：[1]福建农林大学园林学院/兰科植物保护与利用国家林业和草原局重点实验室,福州350002 [2]广西壮族自治区农业科学院园艺研究所,南宁530007

出　　处：《植物遗传资源学报》2022年第2期527-540,共14页Journal of Plant Genetic Resources

基　　金：福建农林大学优秀硕士学位论文基金(1122YS01010);广西重点研发计划(桂科AB16380134);广西农业科学院基本科研任务专项(桂农科2021YT046);福建农林大学科技创新专项资金项目(KFA17331A);花卉产业专家指导服务团队(1891008001)。

摘　　要：木质素是植物次生细胞壁的主要成分,不仅可以为植物提供机械支持、促进水分运输,还对植物应对生物和非生物胁迫具有重要的影响。阳桃属于重要的经济与观赏树种,由于不耐强风、不耐寒、不耐旱等抗逆性条件的限制,严重约束了其种植范围,而木质素对其抗逆性提升具有非常重要的影响。为探究阳桃木质素生物合成过程,首先采用石蜡切片观察了其显微结构,其次测量小枝发育过程中木质素含量及酶活性的变化,最后利用阳桃基因组及转录组数据,对木质素合成相关结构基因及转录因子进行鉴定及生物信息学分析。结果显示,小枝在生长的过程中苯丙氨酸裂解酶(PAL,phenylalanine ammonia-lyase)、肉桂醇脱氢酶(CAD,cinnamyl alcohol dehydrogenase)和过氧化物酶(POD,peroxidase)3种酶活性都呈现上升的趋势,小枝逐渐出现木质部细胞,木质素含量不断增加。在阳桃基因组中共找到与木质素相关的41个结构基因、12个AcaMYBs和11个AcaNACs,表达分析显示同一家族中基因的表达模式存在较大的差异性。qRT-PCR的结果发现AcaPAL1、AcaC3H2、AcaC4H2、AcaF5H1和AcaMYB18基因都表现出明显的组织特异性,表明这些基因是木质素合成相关的特异性基因。结构基因与转录因子共表达网络分析发现AcaNAC29、AcaNAC39和AcaMYB47这3个基因是阳桃木质素合成过程中的关键调控基因。本研究为进一步研究转录因子与结构基因的关系及其对木质素生物合成的影响提供了重要的参考价值。Lignin is the key component in the secondary cell wall of plants,which provides mechanical support and promotes water transport as well as has important impact responding to various biological and abiotic stresses. Averrhoa carambola L. is an important economic and ornamental species,the growing zone of which is restricted by its sensitivity to environmental stress conditions,such as strong wind,cold,and drought.However,lignin has significant impact on the improvement of stress resistance.To explore the lignin biosynthesis process of A. carambola L.,the issue microstructure was visualized using paraffin sections,and the changes of lignin content and enzyme activity were measured at different development stages of twigs. Bioinformatic analyses based on genome sequencing and transcriptome profiling were conducted to identify structural genes and transcription factors that associated to the lignin biosynthesis. The results showed that the increase on the activity of three enzymes(PAL,CAD and POD)and on the lignin content,as well as the appearance of xylem cells were observed along with the twigs development. A total of 41 structural genes,transcription factors(12 AcaMYBs and 11 AcaNACs)were identified in the A. carambola L. genome,followed by analyzing the differential expression patterns of these genes. The results of qRT-PCR found that AcaPAL1,AcaC3H2,AcaC4H2,AcaF5H1 and AcaMYB18 exhibit obvious tissue specific expression pattern,indicating these are specific genes related to lignin biosynthesis. Co-expression network analysis showed that AcaNAC29,AcaNAC39 and AcaMYB47were the essential regulatory genes of lignin biosynthesis. Collectively,this study provided important information to facilitate future research on the transcription factors and structural genes of lignin biosynthesis in A.carambola L..

关 键 词：阳桃 木质素 结构基因 转录因子 表达模式 

分 类 号：Q943.2[生物学—植物学]