The remarkable diversity of the Cyprinidae family highlights the importance of hybridization and gene flow in generating genetic variation,adaptation,and even speciation.However,why do cyprinid fish frequently overcom...The remarkable diversity of the Cyprinidae family highlights the importance of hybridization and gene flow in generating genetic variation,adaptation,and even speciation.However,why do cyprinid fish frequently overcome postzygotic reproductive isolation,a mechanism that normally prevents successful reproduction after fertilization?To address this gap in knowledge,we conducted comparative studies using reciprocal F1hybrid lineages derived from intergeneric hybridization between the cyprinid species Megalobrama amblycephala and Culter alburnus.Utilizing long-read genome sequencing,ATAC-seq,Hi-C,and mRNA-seq technologies,we identified rapid genomic variations,chromatin remodeling,and gene expression changes in the testicular cells of F1hybrid individuals.By analyzing the distribution of these alterations across three gene categories(allelic genes,orphan genes,and testis-specific genes),we found that changes were less pronounced in allelic and testis-specific genes but significantly more pronounced in orphan genes.Furthermore,we hypothesize that rnf212b is a crucial testis-specific gene that regulates spermatogenesis.Our findings suggest that allelic and testis-specific genes potentially mitigate“genomic shock”on reproductive function following hybridization.This research offers potential insights into the formation mechanisms of homoploid hybridization by demonstrating the coordinated interplay of genomic variations,chromatin remodeling,and gene expression changes during testicular development and spermatogenesis.展开更多
Hybridization is a driving force in ecological transitions and speciation,yet direct evidence linking it to adaptive differentiation in natural systems remains limited.This study evaluates the role of hybridization in...Hybridization is a driving force in ecological transitions and speciation,yet direct evidence linking it to adaptive differentiation in natural systems remains limited.This study evaluates the role of hybridization in the speciation of Pinus densata,a keystone forest species on the southeastern Tibetan Plateau.By creating artificialinterspecificF1s and a long-term common garden experiment on the plateau,we provide in situ assessments on 44 growth and physiological traits across four seasons,along with RNA sequencing.We found significantphenotypic divergence between P.densata and its putative parental species P.tabuliformis and P.yunnanensis,with P.densata demonstrating superior growth and dynamic balance between photosynthesis and photoprotection.The F1s closely resembled P.densata in most traits.Gene expression revealed 19%–10%of 34,000 examined genes as differentially expressed in P.densata and F1s relative to mid-parent expression values.Both additive(4%)and non-additive gene actions(5%–6%in F1s,10%–12%in P.densata)were common,while transgressive expression occurred more frequently in the stabilized natural hybrids,illustrating transcriptomic reprogramming brought by hybridization and further divergence by natural selection.We provide compelling evidence for hybridization-derived phenotypic divergence at both physiological and gene expression levels that could have contributed to the adaptation of P.densata to high plateau habitat where both parental species have low fitness.The altered physiology and gene expression in hybrids serve both as a substrate for novel ecological adaptation and as a mechanism for the initiation of reproductive isolation.展开更多
We evaluated a novel and non-destructive method of the electrical impedance spectroscopy(EIS)to elucidate the genetic and evolutionary relationship of homoploid hybrid conifer of Pinus densata(P.d)and its parental spe...We evaluated a novel and non-destructive method of the electrical impedance spectroscopy(EIS)to elucidate the genetic and evolutionary relationship of homoploid hybrid conifer of Pinus densata(P.d)and its parental species Pinus tabuliformis(P.t)and Pinus yunnanensis(P.y),as well as the artificial hybrids of the P.t and P.y.Field common garden tests of96 trees sampled from 760 seedlings and 480 EIS records of 1,440 needles assessed the interspecific variation of the P.d,P.t,P.y and the artificial hybrids.We found that(1)EIS at different frequencies diverged significantly among germplasms;P.y was the highest,P.t was the lowest,and their artificial hybrids were within the range of P.t and P.y;(2)maternal species effect of EIS magnitudes in the hybrids and P.d was stronger than the paternal species characteristics;(3)EIS of the artificial hybrid confirmed the mid-parent and partial maternal species characteristics;(4)unified exponential model of EIS for the interspecific and hybrids can be constructed as|Z|=Af^(-B);(5)cluster analysis for species and hybrid combinations in total corroborated with the previous hybrid model of Pinus densata.Our non-destructive EIS method complemented the previous finding that Pinus densata was originated from P.t and P.y.We conclude that the impedance would be a viable indicator to investigate the interspecific genetic variations of conifers.展开更多
基金supported by the National Natural Science Foundation of China(32341057,32293252,U19A2040,32002372)Hunan Provincial Natural Science Foundation(2022JJ10035)+3 种基金National Key Research and Development Program of China(2023YFD2401602)Special Funds for Construction of Innovative Provinces in Hunan Province(2021NK1010)Earmarked Fund for China Agriculture Research System(CARS-45)111 Project(D20007)。
文摘The remarkable diversity of the Cyprinidae family highlights the importance of hybridization and gene flow in generating genetic variation,adaptation,and even speciation.However,why do cyprinid fish frequently overcome postzygotic reproductive isolation,a mechanism that normally prevents successful reproduction after fertilization?To address this gap in knowledge,we conducted comparative studies using reciprocal F1hybrid lineages derived from intergeneric hybridization between the cyprinid species Megalobrama amblycephala and Culter alburnus.Utilizing long-read genome sequencing,ATAC-seq,Hi-C,and mRNA-seq technologies,we identified rapid genomic variations,chromatin remodeling,and gene expression changes in the testicular cells of F1hybrid individuals.By analyzing the distribution of these alterations across three gene categories(allelic genes,orphan genes,and testis-specific genes),we found that changes were less pronounced in allelic and testis-specific genes but significantly more pronounced in orphan genes.Furthermore,we hypothesize that rnf212b is a crucial testis-specific gene that regulates spermatogenesis.Our findings suggest that allelic and testis-specific genes potentially mitigate“genomic shock”on reproductive function following hybridization.This research offers potential insights into the formation mechanisms of homoploid hybridization by demonstrating the coordinated interplay of genomic variations,chromatin remodeling,and gene expression changes during testicular development and spermatogenesis.
基金supported by the National Natural Science Foundation of China(32171816)T4F program Sweden.
文摘Hybridization is a driving force in ecological transitions and speciation,yet direct evidence linking it to adaptive differentiation in natural systems remains limited.This study evaluates the role of hybridization in the speciation of Pinus densata,a keystone forest species on the southeastern Tibetan Plateau.By creating artificialinterspecificF1s and a long-term common garden experiment on the plateau,we provide in situ assessments on 44 growth and physiological traits across four seasons,along with RNA sequencing.We found significantphenotypic divergence between P.densata and its putative parental species P.tabuliformis and P.yunnanensis,with P.densata demonstrating superior growth and dynamic balance between photosynthesis and photoprotection.The F1s closely resembled P.densata in most traits.Gene expression revealed 19%–10%of 34,000 examined genes as differentially expressed in P.densata and F1s relative to mid-parent expression values.Both additive(4%)and non-additive gene actions(5%–6%in F1s,10%–12%in P.densata)were common,while transgressive expression occurred more frequently in the stabilized natural hybrids,illustrating transcriptomic reprogramming brought by hybridization and further divergence by natural selection.We provide compelling evidence for hybridization-derived phenotypic divergence at both physiological and gene expression levels that could have contributed to the adaptation of P.densata to high plateau habitat where both parental species have low fitness.The altered physiology and gene expression in hybrids serve both as a substrate for novel ecological adaptation and as a mechanism for the initiation of reproductive isolation.
基金funded by National Natural Research Fund 31070591,“Adaptation research of Pinus densata,Pinus tabuliformis,Pinus yunnanensis and the hybrids at high elevation habitats”,P.R.China.
文摘We evaluated a novel and non-destructive method of the electrical impedance spectroscopy(EIS)to elucidate the genetic and evolutionary relationship of homoploid hybrid conifer of Pinus densata(P.d)and its parental species Pinus tabuliformis(P.t)and Pinus yunnanensis(P.y),as well as the artificial hybrids of the P.t and P.y.Field common garden tests of96 trees sampled from 760 seedlings and 480 EIS records of 1,440 needles assessed the interspecific variation of the P.d,P.t,P.y and the artificial hybrids.We found that(1)EIS at different frequencies diverged significantly among germplasms;P.y was the highest,P.t was the lowest,and their artificial hybrids were within the range of P.t and P.y;(2)maternal species effect of EIS magnitudes in the hybrids and P.d was stronger than the paternal species characteristics;(3)EIS of the artificial hybrid confirmed the mid-parent and partial maternal species characteristics;(4)unified exponential model of EIS for the interspecific and hybrids can be constructed as|Z|=Af^(-B);(5)cluster analysis for species and hybrid combinations in total corroborated with the previous hybrid model of Pinus densata.Our non-destructive EIS method complemented the previous finding that Pinus densata was originated from P.t and P.y.We conclude that the impedance would be a viable indicator to investigate the interspecific genetic variations of conifers.
基金The National Natural Science Foundation of China(NSFC 31270271 to J.H.Chen)the Project of Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No.:KSCX2-EW-J-24)+1 种基金Yunnan Natural Science Foundation(2010CD109 to J.H.Chen)the Youth Innovation Promotion Association,CAS
