Heterosis is an important biological phenomenon and widely applied in agriculture.Although many studies have been performed by using vegetative organs of F_(1) hybrid plants,how heterosis (or hybrid vigor) is initiate...Heterosis is an important biological phenomenon and widely applied in agriculture.Although many studies have been performed by using vegetative organs of F_(1) hybrid plants,how heterosis (or hybrid vigor) is initiated and formed,particularly the underlying molecular mechanism,remain elusive.Hybrid contemporary seeds of rice indica varieties 9311 and PA64 were innovatively used and analysis of DNA methylome of embryo and endosperm at early developing stages revealed the globally decreased DNA methylation.Genes,especially those relate to hormones function and transcriptional regulation present non-additive methylation.Previously identified heterosis-related superior genes are non-additively methylated in early developing hybrid contemporary seeds,suggesting that key genes/loci responsible for heterosis are epigenetically modified even in early developing hybrid seeds and hypomethylation of hybrid seeds after cross-pollination finally result in the long-term transcriptional change of F_(1) hybrid vegetative tissues after germination,demonstrating that altered DNA methylation in hybrid seeds is essential for initiation regulation and maintenance of heterosis exhibiting in F_(1) hybrid plants.Notably,a large number of genes show non-additive methylation in the endosperm of reciprocal hybrids,suggesting that endosperm might also contribute to heterosis.展开更多
Potato is the fourth most important food crop in the world.Although with a long history for breeding approaches,genomic information and association between genes and agronomic traits remain largely unknown particularl...Potato is the fourth most important food crop in the world.Although with a long history for breeding approaches,genomic information and association between genes and agronomic traits remain largely unknown particularly in autotetraploid potato cultivars,which limit the molecular breeding progression.By resequencing the genome of 108 main cultivar potato accessions with rich genetic diversity and population structure from International Potato Center,with approximate 20-fold coverage,we revealed more than 27 million Single Nucleotide Polymorphisms and~3 million Insertion and Deletions with high quality and accuracy.Domestication analysis and genome-wide association studies(GWAS)identified candidate loci related to photoperiodic flowering time and temperature sensitivity as well as disease resistance,providing informative insights into the selection and domestication of cultivar potato.In addition,GWAS with GWASploy for 25 agronomic traits identified candidate loci by association signals,especially those related to tuber size,small-sized tuber weight and tuber thickness that was also validated by transcriptome analysis.Our study provides a valuable resource that facilitates the elucidation of domestication process as well as the genetic studies and agronomic improvement of autotetraploid potato.展开更多
基金supported by the Ministry of Science and Technology of China (2012CB944804)the National Transformation Science and Technology Program (2016ZX08001006-009)the National Key Research and Development Program of China (2016YFD0100501, 2016YFD0100902)。
文摘Heterosis is an important biological phenomenon and widely applied in agriculture.Although many studies have been performed by using vegetative organs of F_(1) hybrid plants,how heterosis (or hybrid vigor) is initiated and formed,particularly the underlying molecular mechanism,remain elusive.Hybrid contemporary seeds of rice indica varieties 9311 and PA64 were innovatively used and analysis of DNA methylome of embryo and endosperm at early developing stages revealed the globally decreased DNA methylation.Genes,especially those relate to hormones function and transcriptional regulation present non-additive methylation.Previously identified heterosis-related superior genes are non-additively methylated in early developing hybrid contemporary seeds,suggesting that key genes/loci responsible for heterosis are epigenetically modified even in early developing hybrid seeds and hypomethylation of hybrid seeds after cross-pollination finally result in the long-term transcriptional change of F_(1) hybrid vegetative tissues after germination,demonstrating that altered DNA methylation in hybrid seeds is essential for initiation regulation and maintenance of heterosis exhibiting in F_(1) hybrid plants.Notably,a large number of genes show non-additive methylation in the endosperm of reciprocal hybrids,suggesting that endosperm might also contribute to heterosis.
文摘Potato is the fourth most important food crop in the world.Although with a long history for breeding approaches,genomic information and association between genes and agronomic traits remain largely unknown particularly in autotetraploid potato cultivars,which limit the molecular breeding progression.By resequencing the genome of 108 main cultivar potato accessions with rich genetic diversity and population structure from International Potato Center,with approximate 20-fold coverage,we revealed more than 27 million Single Nucleotide Polymorphisms and~3 million Insertion and Deletions with high quality and accuracy.Domestication analysis and genome-wide association studies(GWAS)identified candidate loci related to photoperiodic flowering time and temperature sensitivity as well as disease resistance,providing informative insights into the selection and domestication of cultivar potato.In addition,GWAS with GWASploy for 25 agronomic traits identified candidate loci by association signals,especially those related to tuber size,small-sized tuber weight and tuber thickness that was also validated by transcriptome analysis.Our study provides a valuable resource that facilitates the elucidation of domestication process as well as the genetic studies and agronomic improvement of autotetraploid potato.
