【作者】 孙健； 姚方杰； 鲁丽鑫； 张友民； 方明； 马晓旭； 邵凯胜； 孙旭；

【Author】 Jian Sun;Fangjie Yao;Lixin Lu;Youmin Zhang;Ming Fang;Xiaoxu Ma;Kaisheng Shao;Xu Sun;Engineering Research Centre of Chinese Ministry of Education for Edible and Medicinal Fungi,Jilin Agricultural University;Lab of Genetic Breeding of Edible Mushroom,Horticultural,College of Horticulture,Jilin Agricultural University;

【机构】 吉林农业大学食药用菌教育部工程研究中心； 吉林农业大学园艺学院；

【摘要】 黑木耳具有罕见的耐旱性,但其耐旱机制尚未进行系统研究。本研究以13株黑木耳菌株为研究对象,通过0和20%PEG模拟干旱胁迫,探究黑木耳的生理响应及其耐旱机制。20%PEG处理后,黑木耳的可溶性糖、可溶性蛋白质、超氧化物歧化酶、过氧化氢酶、丙二醛、生物量六项生理指标差异显著。黑木耳的耐旱性存在菌株间差异,根据隶属函数值对供试菌株进行耐旱性评价,将其分为四类:第一类为高度耐旱菌株:A;第二类为耐旱菌株:A127和C;第三类为中度耐旱菌株,包括:A124、A14、A386、A462、A184、A496、A125和B;第四类为干旱敏感菌株包括A356和A508。对耐旱菌株C干旱胁迫处理前后进行转录组测序,共获得1762个差异表达基因,其中上调表达基因798个,下调表达基因964个。通过KEGG富集分析,首次发现黑木耳海藻糖合成途径为TPS-TPP途径,且参与黑木耳干旱胁迫响应。同时,鉴定出海藻糖合成的两个关键酶基因:海藻糖-6-磷酸合成酶(AhTPS)和海藻糖-6-磷酸磷酸酶(AhTPP),并且在干旱胁迫后显著上调表达。11株菌株干旱胁迫处理后海藻糖含量显著增加,明确了海藻糖参与黑木耳干旱胁迫调控的机制。本研究首次发现海藻糖合成途径参与食用菌干旱胁迫响应,为黑木耳遗传改良和耐旱菌株的选育提供参考,也为其它食用菌抗性育种奠定理论基础。更多还原

【Abstract】 Auricularia heimuer has rare drought tolerance,but its mechanism has not been systematically studied.We selected 13 strains of A.heimuer to explore its physiological response and drought tolerance mechanism before and after simulated drought stress with 0 and 20%polyethylene glycol.After treatment with 20% PEG,there were significant differences in the physiological indicators of soluble sugar,soluble protein,superoxide dismutase,catalase,malondialdehyde,and biomass in A.heimuer.There were also differences in drought tolerance among the different strains of A.heimuer.The tested strains were classified into four categories according to their membership values:the first category was highly drought-tolerant strain A;the second was drought-tolerant strains A127 and C;the third was moderately drought-tolerant strains A124,A14,A386,A462,A184,A496,A125,and B;and the fourth was drought-sensitive strains A356 and A508.Transcriptome analysis was performed on C before and after drought stress treatment,and 1762 DEGs were obtained,including 798 up-and 964 down-regulated genes.Through KEGG enrichment analysis,it was found for the first time that the synthesis pathway of trehalose in A.heimuer is TPS-TPP,which is involved in the response of A.heimuer to drought stress.In addition,two key enzyme genes involved in trehalose synthesis were identified,trehalose-6-phosphate synthase(AhTPS) and trehalose-6-phosphate phosphatase(AhTPP),which were significantly up-regulated after drought stress.The trehalose content significantly increased in 11 strains after drought stress treatment,confirming the involvement of trehalose in the regulation mechanism of A.heimuer under drought stress.This study discovered,for the first time,that the synthesis pathway of trehalose is involved in the response of edible fungi to drought stress,thus providing a reference for the genetic improvement of A.heimuer and the selection of drought-tolerant strains,and laying a theoretical foundation for the resistance breeding of other edible fungi.更多还原