Convergent evolution of AP2/ERF Ⅲ and IX subfamilies through recurrent polyploidization and tandem duplication during eudicot adaptation to paleoenvironmental changes  

作　　者：Liangyu Guo Shuo Wang Yuqi Nie Yirong Shen Xiaoxue Ye Wenwu Wu 

机构地区：[1]State Key Laboratory of Subtropical Silviculture,School of Forestry and Biotechnology,Zhejiang A&F University,Lin’an,Hangzhou 311300,China [2]Institute of Tropical Biosciences and Biotechnology,Chinese Academy of Tropical Agricultural Sciences,Haikou 571101,China

出　　处：《Plant Communications》2022年第6期74-88,共15页植物通讯（英文）

基　　金：supported by the National Natural Science Foundation of China(grant number 31871233);the National Key R&D Program of China(2018YFD1000604).

摘　　要：Whole-genome duplication(WGD or polyploidization)has been suggested as a genetic contributor to angiosperm adaptation to environmental changes.However,many eudicot lineages did not undergo recent WGD(R-WGD)around and/or after the Cretaceous-Paleogene(K-Pg)boundary,times of severe environmental changes;how those plants survived has been largely ignored.Here,we collected 22 plants from major branches of the eudicot phylogeny and classified them into two groups according to the occurrence or absence of R-WGD:12 R-WGD-containing plants(R-WGD-Y)and 10 R-WGD-lacking plants(R-WGD-N).Subsequently,we identified 496 gene-rich families in R-WGD-Y and revealed that members of the AP2/ERF transcription factor family were convergently over-retained after R-WGDs and showed exceptional cold stimulation.The evolutionary trajectories of the AP2/ERF family were then compared between R-WGD-Y and R-WGD-N to reveal convergent expansions of the AP2/ERF Ⅲ and IX subfamilies through recurrent independent WGDs and tandem duplications(TDs)after the radiation of the plants.The expansions showed coincident enrichments in-times around and/or after the K-Pg boundary,when global cooling was a major environmental stressor.Consequently,convergent expansions and co-retentions of AP2/ERF Ⅲ C-repeat binding factor(CBF)duplicates and their regulons in different eudicot lineages contributed to the rewiring of cold-specific regulatory networks.Moreover,promoter analysis of cold-responsive AP2/ERF genes revealed an underlying cis-regulatory code(G-box:CACGTG).We propose a seesaw model of WGDs and TDs in the convergent expansion of AP2/ERF Ⅲ and IX genes that has contributed to eudicot adaptation during paleoenvironmental changes,and we suggest that TD may be a reciprocal/alternative mechanism for genetic innovation in plants that lack WGD.

关 键 词：POLYPLOIDIZATION tandem duplication AP2/ERF family adaptive evolution global cooling abiotic stress 

分 类 号：Q94[生物学—植物学]