基于金观音(Camellia sinensis)单体型基因组CsUGT等位基因的鉴定及表达  

Identification and Expression of CsUGT Alleles Based on Haplotype-resolved Genomes of Camellia sinensis Jinguanyin

作　　者：雷小梅 张宇航 谷梦雅 郑玉成 叶乃兴[1] LEI Xiao-mei;ZHANG Yu-hang;GU Meng-ya;ZHENG Yu-cheng;YE Nai-xing(College of Horticulture,Fujian Agriculture and Forestry University/Key Laboratory of Tea Science at Universities in Fujian,Fuzhou,Fujian 350002,China)

机构地区：[1]福建农林大学园艺学院/茶学福建省高校重点实验室,福建福州350002

出　　处：《茶叶学报》2024年第3期11-33,共23页Acta Tea Sinica

基　　金：中国乌龙茶产业协同创新中心开放基金(2024W01);福建张天福茶叶发展基金会科技创新基金(FJZTF01)。

摘　　要：【目的】植物的尿苷二磷酸糖基转移酶(UGT)是催化次生代谢物糖基化的关键酶,UGT基因主要参与植物逆境胁迫的响应。对CsUGT等位基因进行鉴定与表达分析,为其在茶树抗性及乌龙茶加工中香气形成的作用提供理论参考。【方法】基于金观音(Camellia sinensis‘Jinguanyin’)单体型基因组,利用生物信息学方法分析,并通过实时荧光定量PCR技术分析CsUGT基因在低温(4℃)、干旱(10%PEG-6000溶液)和激素(100μmol·L^(−1)MeJA溶液)处理下0、3、6、12和24 h的表达,以及CsUGT基因在金观音乌龙茶加工过程中鲜叶、萎凋、一摇、二摇、三摇和杀青前的表达。【结果】生物信息学分析结果表明,从金观音单体型基因组中鉴定出了142对等位基因,多数定位于叶绿体中,并基于进化树将这些基因分为5个亚家族。CsUGT等位基因的结构较保守,相同基因的亲本等位基因的结构相似。转录组数据分析表明,发现多数CsUGT等位基因具有组织表达特性。实时荧光定量PCR检测发现,在MeJA处理下,CsUGT002、CsUGT047和CsUGT091的表达量在6 h达到峰值;在低温和干旱处理下,部分CsUGT基因的表达量分别在3或24 h时达到峰值。此外,在金观音乌龙茶加工过程中,CsUGT115的表达量显著上调,部分CsUGT基因在三摇时的表达量达到峰值。【结论】CsUGT蛋白多数为酸性和亲水性蛋白,并定位于叶绿体中;CsUGT等位基因结构较保守具有组织表达特性,部分CsUGT基因参与调控茶树的逆境胁迫及乌龙茶加工工艺中摇青时的香气合成。【Objective】Key genes responsible of generating uridine diphosphate glycosyltransferase(UGT)that catalyzes the glycosylation of the secondary metabolism associated with the stress response of Camellia sinensis were identified,and expressions under stress analyzed to decipher the aroma formation of oolong tea in processing.【Method】Based on the haplotype-resolved genomes of C.sinensis Jinguanyin,CsUGT alleles were analyzed by bioinformatics and RT-PCR.Expressions of CsUGT at 0,3,6,12,and 24 h under stresses of low temperature(4℃),drought(10%PEG-6000 solution),or hormone(100μmol·L^(−1)MeJA solution)as well as in the young leaves,withering,post-1st turning-over,post-2nd turning-over,post-3rd turning-over,and before firing in the processing stages of Jinguanyin oolong tea were determined.【Result】The 142 CsUGT allele pairs identified from the haplotype-resolved genomes were mostly in the chloroplasts and could be divided into 5 subfamilies based on the evolutionary tree.These alleles were conserved and similar in structure when came from the same parent.Expressions of most of the alleles were tissue specific playing an important role in different organs of the tea plant.The expressions of CsUGT002,CsUGT047,and CsUGT091 peaked at 6h under MeJA treatment,while some peaked in 3 h under cold stress and 24 h under drought conditions.The expression of CsUGT115 was significantly upregulated during processing,while some others peaked at the 3rd turning-over stage.【Conclusion】Most CsUGTs were acidic,hydrophilic,and found in the chloroplast.Expressions of CsUGT alleles were tissue specific.Some CsUGTs associated with the aroma synthesis were activated by the stresses exerted by the tea processing.

关 键 词：茶树 金观音 尿苷二磷酸糖基转移酶 等位基因 逆境胁迫 香气 生物信息学 

分 类 号：TS272[农业科学—茶叶生产加工]