DNA methylation confers epigenetic regulation on gene expression and thereby on various biological processes.Tomato has emerged as an excellent system to study the function of DNA methylation in plant development.To d...DNA methylation confers epigenetic regulation on gene expression and thereby on various biological processes.Tomato has emerged as an excellent system to study the function of DNA methylation in plant development.To date,regulation and function of DNA methylation maintenance remains unclear in tomato plants.Here,we report the critical function of tomato(Solanum lycopersicum)Methyltransferase 1(Sl MET1)in plant development and DNA methylome and transcriptome regulation.Using CRISPR-Cas9 gene editing,we generated slmet1 mutants and observed severe developmental defects with a frame-shift mutation,including small and curly leaves,defective inflorescence,and parthenocarpy.In leaf tissues,mutations in Sl MET1 caused CG hypomethylation and CHH hypermethylationon a whole-genome scale,leading to a disturbed transcriptome including ectopic expression of many RIN target genes such as ACC2 in leaf tissues,which are normally expressed in fruits.Neither the CG hypomethylation nor CHH hypermethylation in the slmet1 mutants is related to tissue culture.Meanwhile,tissue culture induces non-CG hypomethylation,which occurs more frequently at gene regions than at TE regions.Our results depict Sl MET1-and tissue culture-dependent tomato DNA methylomes,and that Sl MET1 is required for maintaining a normal transcriptome and normal development of tomato.展开更多
RNA-directed DNA methylation(Rd DM) is a plant-specific de novo DNA methylation pathway,which has extensive cross-talk with histone modifications. Here, we report that the maize RdDM regulator SAWADEE HOMEODOMAIN HOMO...RNA-directed DNA methylation(Rd DM) is a plant-specific de novo DNA methylation pathway,which has extensive cross-talk with histone modifications. Here, we report that the maize RdDM regulator SAWADEE HOMEODOMAIN HOMOLOG 2(SHH2) is an H3 K9 me1 reader. Our structural studies reveal that H3 K9 me1 recognition is achieved by recognition of the methyl group via a classic aromatic cage and hydrogen-bonding and salt-bridge interactions with the free protons of the mono-methyllysine. The di-and tri-methylation states disrupt the polar interactions, decreasing the binding affinity. Our study reveals a monomethyllysine recognition mechanism which potentially links RdDM to H3 K9 me1 in maize.展开更多
基金supported by the Chinese Academy of Sciences and by the Thousand Talents Program for Young Scientists,China
文摘DNA methylation confers epigenetic regulation on gene expression and thereby on various biological processes.Tomato has emerged as an excellent system to study the function of DNA methylation in plant development.To date,regulation and function of DNA methylation maintenance remains unclear in tomato plants.Here,we report the critical function of tomato(Solanum lycopersicum)Methyltransferase 1(Sl MET1)in plant development and DNA methylome and transcriptome regulation.Using CRISPR-Cas9 gene editing,we generated slmet1 mutants and observed severe developmental defects with a frame-shift mutation,including small and curly leaves,defective inflorescence,and parthenocarpy.In leaf tissues,mutations in Sl MET1 caused CG hypomethylation and CHH hypermethylationon a whole-genome scale,leading to a disturbed transcriptome including ectopic expression of many RIN target genes such as ACC2 in leaf tissues,which are normally expressed in fruits.Neither the CG hypomethylation nor CHH hypermethylation in the slmet1 mutants is related to tissue culture.Meanwhile,tissue culture induces non-CG hypomethylation,which occurs more frequently at gene regions than at TE regions.Our results depict Sl MET1-and tissue culture-dependent tomato DNA methylomes,and that Sl MET1 is required for maintaining a normal transcriptome and normal development of tomato.
基金supported by National Natural Science Foundation of China(31770782)the Ministry of Science and Technology of China(2016YFA0503200)+1 种基金the Shenzhen Science and Technology Program(JCYJ20200109110403829 and KQTD20190929173906742)Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes(2019KSYS006)to J.D.
文摘RNA-directed DNA methylation(Rd DM) is a plant-specific de novo DNA methylation pathway,which has extensive cross-talk with histone modifications. Here, we report that the maize RdDM regulator SAWADEE HOMEODOMAIN HOMOLOG 2(SHH2) is an H3 K9 me1 reader. Our structural studies reveal that H3 K9 me1 recognition is achieved by recognition of the methyl group via a classic aromatic cage and hydrogen-bonding and salt-bridge interactions with the free protons of the mono-methyllysine. The di-and tri-methylation states disrupt the polar interactions, decreasing the binding affinity. Our study reveals a monomethyllysine recognition mechanism which potentially links RdDM to H3 K9 me1 in maize.