Genetic information has been instrumental in elucidating the relationship between the East Asian Summer Monsoon(EASM)and subtropical evergreen broad-leaved forests(EBLFs).However,how the genomic insights of EBLFs’spe...Genetic information has been instrumental in elucidating the relationship between the East Asian Summer Monsoon(EASM)and subtropical evergreen broad-leaved forests(EBLFs).However,how the genomic insights of EBLFs’species correspond to environmental shifts induced by the EASM remains limited.In this study,we investigated the adaptive mechanisms of evergreen Engelhardia species in response to the EASM through genome sequencing and comparative genomic analyses from the de novo genome assemblies of fiveclosely related Engelhardia taxa and one Rhoiptelea species.Our findingsrevealed that the divergence of evergreen trees from their sister deciduous species is closely associated with the onset and intensification of the EASM.This genomic transitionmayhave coincided with a significantexpansion of the terpene synthase(TPS)gene family in E.fenzelii,driven by four distinct modes of gene duplication.This expansion enhances the biosynthesis of terpene volatiles,providing a defensive mechanism against potential herbivory in EASM affected environments.We also identifieda shared whole-genome duplication(WGD)event across Engelhardia,along with substantial differences in transposable element(TE)composition and activity,which contributed to genome size variation between E.fenzelii and E.roxburghiana.In addition,demographic analyses revealed a continuous population decline over the past 10 million years,further exacerbated by recenthumandisturbance,underscoring the conservation urgency for these species.These results not only provide preliminary insights into the complex evolutionary dynamics within the Engelhardia genus from genomic insights(e.g.,the intricate relationships between genomic variations,environmental changes,and adaptive responses driven by significantclimatic events such as the EASM),but also provides valuable insights into the conservation significance of EBLFs.展开更多
A strong （weak） East Asian summer monsoon （EASM） is usually concurrent with the tripole pattern of North Atlantic SST anomalies on the interannual timescale during summer, which has positive （negative） SST anoma...A strong （weak） East Asian summer monsoon （EASM） is usually concurrent with the tripole pattern of North Atlantic SST anomalies on the interannual timescale during summer, which has positive （negative） SST anomalies in the northwestern North Atlantic and negative （positive） SST anomalies in the subpolar and tropical ocean. The mechanisms responsible for this linkage are diagnosed in the present study. It is shown that a barotropie wave-train pattern occurring over the Atlantic-Eurasia region likely acts as a link between the EASM and the SST tripole during summer. This wave-train pattern is concurrent with geopotential height anomalies over the Ural Mountains, which has a substantial effect on the EASM. Diagnosis based on observations and linear dynamical model results reveals that the mechanism for maintaining the wave-train pattern involves both the anomalous diabatic heating and synoptic eddy-vorticity forcing. Since the North Atlantic SST tripole is closely coupled with the North Atlantic Oscillation （NAO）, the relationships between these two factors and the EASM are also examined. It is found that the connection of the EASM with the summer SST tripole is sensitive to the meridional location of the tripole, which is characterized by large seasonal variations due to the north-south movement of the activity centers of the NAO. The SST tripole that has a strong relationship with the EASM appears to be closely coupled with the NAO in the previous spring rather than in the simultaneous summer.展开更多
基金supported by the National Natural Science Foundation of China(No.42171063)Southeast Asia Biodiversity Research Institute,Chinese Academy of Sciences(No.Y4ZK111B01)+6 种基金the Special Fund for ScientificResearch of Shanghai Landscaping&City Appearance Administrative Bureau(G242414,G242416)the“Yunnan Revitalization Talent Support Program”in Yunnan Province(XDYC-QNRC-2022-0028)Yunnan Revitalization Talent Support Program“Innovation Team”Project(202405AS350019)the CAS“Light of West China”Programthe 14th Five-Year Plan of Xishuangbanna Tropical Botanical Garden,Chinese Academy Sciences(XTBG-1450303)the European Research Council(ERC)under the European Union's Horizon 2020 research and innovation program(No.833522)GhentUniversity(Methusalem funding,BOF.MET.2021.0005.01).
文摘Genetic information has been instrumental in elucidating the relationship between the East Asian Summer Monsoon(EASM)and subtropical evergreen broad-leaved forests(EBLFs).However,how the genomic insights of EBLFs’species correspond to environmental shifts induced by the EASM remains limited.In this study,we investigated the adaptive mechanisms of evergreen Engelhardia species in response to the EASM through genome sequencing and comparative genomic analyses from the de novo genome assemblies of fiveclosely related Engelhardia taxa and one Rhoiptelea species.Our findingsrevealed that the divergence of evergreen trees from their sister deciduous species is closely associated with the onset and intensification of the EASM.This genomic transitionmayhave coincided with a significantexpansion of the terpene synthase(TPS)gene family in E.fenzelii,driven by four distinct modes of gene duplication.This expansion enhances the biosynthesis of terpene volatiles,providing a defensive mechanism against potential herbivory in EASM affected environments.We also identifieda shared whole-genome duplication(WGD)event across Engelhardia,along with substantial differences in transposable element(TE)composition and activity,which contributed to genome size variation between E.fenzelii and E.roxburghiana.In addition,demographic analyses revealed a continuous population decline over the past 10 million years,further exacerbated by recenthumandisturbance,underscoring the conservation urgency for these species.These results not only provide preliminary insights into the complex evolutionary dynamics within the Engelhardia genus from genomic insights(e.g.,the intricate relationships between genomic variations,environmental changes,and adaptive responses driven by significantclimatic events such as the EASM),but also provides valuable insights into the conservation significance of EBLFs.
基金jointly supported by the National Basic Research Program of China (Grant Nos. 2010CB950404, 2013CB430203, 2010CB950501 and 2012CB955901)the National Natural Science Foundation of China (Grant No. 41205058)+1 种基金the China Postdoctoral Science Foundation (Grant No. 2012M510634)the National Science and Technology Support Program of China (Grant No. 2009BAC51B05)
文摘A strong （weak） East Asian summer monsoon （EASM） is usually concurrent with the tripole pattern of North Atlantic SST anomalies on the interannual timescale during summer, which has positive （negative） SST anomalies in the northwestern North Atlantic and negative （positive） SST anomalies in the subpolar and tropical ocean. The mechanisms responsible for this linkage are diagnosed in the present study. It is shown that a barotropie wave-train pattern occurring over the Atlantic-Eurasia region likely acts as a link between the EASM and the SST tripole during summer. This wave-train pattern is concurrent with geopotential height anomalies over the Ural Mountains, which has a substantial effect on the EASM. Diagnosis based on observations and linear dynamical model results reveals that the mechanism for maintaining the wave-train pattern involves both the anomalous diabatic heating and synoptic eddy-vorticity forcing. Since the North Atlantic SST tripole is closely coupled with the North Atlantic Oscillation （NAO）, the relationships between these two factors and the EASM are also examined. It is found that the connection of the EASM with the summer SST tripole is sensitive to the meridional location of the tripole, which is characterized by large seasonal variations due to the north-south movement of the activity centers of the NAO. The SST tripole that has a strong relationship with the EASM appears to be closely coupled with the NAO in the previous spring rather than in the simultaneous summer.
