Understanding the role of heterotic genes in contributing to heterosis is essential for advancing hybrid breeding.We analyzed plant height(PH),ear height(EH),and transcriptomic data from a maize hybrid pop-ulation.Gen...Understanding the role of heterotic genes in contributing to heterosis is essential for advancing hybrid breeding.We analyzed plant height(PH),ear height(EH),and transcriptomic data from a maize hybrid pop-ulation.Genome-wide association studies(GWASs)revealed that dominance effects of quantitative trait loci(QTLs)play a significant role in hybrid traits and mid-parent heterosis.By integrating GWAS,expression GWAS(eGWAS),and module eGWAS analysis,we prioritized six candidate heterotic genes underlying six QTLs,including one QTL that spans the bZIP29 gene.In the hybrid population,bZIP29 exhibits additive expression and dominance effects for both hybrid traits and mid-parent heterosis,with its favorable allele correlating positively with PH and EH.bZIP29 demonstrates dominance or over-dominance patterns in hy-brids derived from crosses between transgenic and wild-type lines,contingent upon its expression.A tsCUT&Tag assay revealed that bZIP29 protein binds directly to a gene regulated by its associated expres-sion QTL(eQTL)and six genes within expression modules governed by its associated module-eQTLs(meQTLs).Regulatory networks involving bZIP29 are more extensive in hybrid subpopulations than in the parental population.This study offers insights into key heterotic genes and networks that underpin the robust growth of hybrid maize.展开更多
基金supported by the National Key R&D Program of China(2023YFF1000400)the Biological Breeding-National Science and Technology Major Project(2023ZD04076)+1 种基金the China Agriculture Research System of Maize(CARS-02-13)the Innovation Program of the Chinese Academy of Agricultural Sciences.
文摘Understanding the role of heterotic genes in contributing to heterosis is essential for advancing hybrid breeding.We analyzed plant height(PH),ear height(EH),and transcriptomic data from a maize hybrid pop-ulation.Genome-wide association studies(GWASs)revealed that dominance effects of quantitative trait loci(QTLs)play a significant role in hybrid traits and mid-parent heterosis.By integrating GWAS,expression GWAS(eGWAS),and module eGWAS analysis,we prioritized six candidate heterotic genes underlying six QTLs,including one QTL that spans the bZIP29 gene.In the hybrid population,bZIP29 exhibits additive expression and dominance effects for both hybrid traits and mid-parent heterosis,with its favorable allele correlating positively with PH and EH.bZIP29 demonstrates dominance or over-dominance patterns in hy-brids derived from crosses between transgenic and wild-type lines,contingent upon its expression.A tsCUT&Tag assay revealed that bZIP29 protein binds directly to a gene regulated by its associated expres-sion QTL(eQTL)and six genes within expression modules governed by its associated module-eQTLs(meQTLs).Regulatory networks involving bZIP29 are more extensive in hybrid subpopulations than in the parental population.This study offers insights into key heterotic genes and networks that underpin the robust growth of hybrid maize.
