Duplication and transcriptional divergence of three Kunitz protease inhibitor genes that modulate insect and pathogen defenses in tea plant(Camellia sinensis)  

作　　者：Junyan Zhu Yaxian He Xiaomei Yan Lu Liu Rui Guo Xiaobo Xia Daojie Cheng Xiaozeng Mi Lidiia Samarina Shenrui Liu Enhua Xia Chaoling Wei 

机构地区：[1]State Key Laboratory of Tea Plant Biology and Utilization/Key Laboratory of Tea Biology and Processing,Ministry of Agriculture,Anhui Agricultural University,West 130 Changjiang Road,Hefei 230036 Anhui,People’s Republic of China [2]Russian Research Institute of Floriculture and Subtropical Crops,354002Yana Fabritsiusa st.2/28,Sochi,Russian Federation

出　　处：《Horticulture Research》2019年第1期170-181,共12页园艺研究（英文）

基　　金：supported by the National Key Research and Development Program of China(2018YFD1000601);the National Natural Science Foundation of China(31171608);the Special Innovative Province Construction in Anhui Province(15czs08032);the Special Project for Central Guiding Science and Technology Innovation of Region in Anhui Province(2016080503B024);the Program for Changjiang Scholars and Innovative Research Team in University(IRT1101).

摘　　要：Kunitz protease inhibitors(KPIs)are ubiquitous in plants and act as crucial compounds in defense responses against insect attack and pathogen infection.However,the influence of gene duplication on the postdivergence of the CsKPI genes involved in biotic stresses in tea plant is not well known.Here,we identified three CsKPI genes from tea plant(Camellia sinensis)and characterized their expression and evolutionary patterns among plant species.We found that CsKPI1,CsKPI2,and CsKPI3 diverged from their common ancestor 72.94 million years ago(MYA),and the tandem duplication of CsKPI2 and CsKPI3 occurred 26.78 MYA.An in vitro protein assay showed that the three CsKPI proteins were functional and inhibited the production of p-nitroanilide(PNA)from an artificial substrate.The three CsKPI-GFP fusion proteins localized to the cytoplasm.We showed that salicylic acid(SA)and transcripts of CsKPI2 and CsKPI3 significantly accumulated after infection with Glomerella cingulata.The application of exogenous SA stimulated the high expression of both CsKPI2 and CsKPI3 by activating cis-elements within their promoters.Under Ectropis oblique attack,CsKPI1 expression and jasmonic acid(JA)levels were more abundant in both insect-damaged leaf tissues and undamaged neighboring leaves.The application of jasmonic acid methyl ester elicited high expression levels of CsKPI1,suggesting that CsKPI1 accumulation requires JA production in tea plant.The overall findings suggest that the transcriptional divergence of KPI genes after duplication led to the specialized role of CsKPI1 in the physiological response to insect stress;the functional conservation between CsKPI2 and CsKPI3 confers resistance to pathogen infection in tea plant.

关 键 词：SINENSIS inhibited DIVERGENCE 

分 类 号：R73[医药卫生—肿瘤]