Rice(Oryza sativa),a major staple throughout the world and a model system for plant genomics and breeding,was the first crop genome sequenced almost two decades ago.However,reference genomes for all higher organisms t...Rice(Oryza sativa),a major staple throughout the world and a model system for plant genomics and breeding,was the first crop genome sequenced almost two decades ago.However,reference genomes for all higher organisms to date contain gaps and missing sequences.Here,we report the assembly and analysis of gap-free reference genome sequences for two elite O.sativa xian/indica rice varieties,Zhenshan 97 and Minghui 63,which are being used as a model system for studying heterosis and yield.Gap-free reference genomes provide the opportunity for a global view of the structure and function of centromeres.We show that all rice centromeric regions share conserved centromere-specific satellite motifs with different copy numbers and structures.In addition,the similarity of CentO repeats in the same chromosome is higher than across chromosomes,supporting a model of local expansion and homogenization.Both genomes have over 395 non-TE genes located in centromere regions,of which∼41%are actively transcribed.Two large structural variants at the end of chromosome 11 affect the copy number of resistance genes between the two genomes.The availability of the two gap-free genomes lays a solid foundation for further understanding genome structure and function in plants and breeding climate-resilient varieties.展开更多
Advances in the next-generation and long-read sequencing technologies have promoted the development of genome-wide comparative genomics analysis,and constructing pangenomes and identifying structural variations(SVs)ar...Advances in the next-generation and long-read sequencing technologies have promoted the development of genome-wide comparative genomics analysis,and constructing pangenomes and identifying structural variations(SVs)are becoming the frontier of genomics.Comparative genomics is of critical importance for determining the gene function and the evolutionary basis of traits.展开更多
Dear Editor,The genus Citrus comprises more than 30 species worldwide(Swingle,1943).However,citrus genetics and traditional breeding are hindered due to asexual reproduction,long generation time,and empirical utilizat...Dear Editor,The genus Citrus comprises more than 30 species worldwide(Swingle,1943).However,citrus genetics and traditional breeding are hindered due to asexual reproduction,long generation time,and empirical utilization of the germplasm.The whole-genome information of different citrus species accelerates the genetic studies and improves the breeding efficiency by high-density markers.展开更多
基金This research was supported by the Natinal Key Research and Development Program of China(2016YFD0100904 and 2016YFD0100802)the National Natural Science Foundation of China(31871269)+1 种基金the Hubei Provincial Natural Science Foundation of China(2019CFA014)Fundamental Research Funds for the Central Universities(2662020SKPY010 to J.Z.).
文摘Rice(Oryza sativa),a major staple throughout the world and a model system for plant genomics and breeding,was the first crop genome sequenced almost two decades ago.However,reference genomes for all higher organisms to date contain gaps and missing sequences.Here,we report the assembly and analysis of gap-free reference genome sequences for two elite O.sativa xian/indica rice varieties,Zhenshan 97 and Minghui 63,which are being used as a model system for studying heterosis and yield.Gap-free reference genomes provide the opportunity for a global view of the structure and function of centromeres.We show that all rice centromeric regions share conserved centromere-specific satellite motifs with different copy numbers and structures.In addition,the similarity of CentO repeats in the same chromosome is higher than across chromosomes,supporting a model of local expansion and homogenization.Both genomes have over 395 non-TE genes located in centromere regions,of which∼41%are actively transcribed.Two large structural variants at the end of chromosome 11 affect the copy number of resistance genes between the two genomes.The availability of the two gap-free genomes lays a solid foundation for further understanding genome structure and function in plants and breeding climate-resilient varieties.
基金supported by the National Natural Science Foundation of China(32100526,31871269)Hubei Provincial Natural Science Foundation of China(2019CFA014)+1 种基金Innovation Project of Guangxi Graduate Education(YCSW2022038)the starting research grant for High-level Talents from Guangxi University。
文摘Advances in the next-generation and long-read sequencing technologies have promoted the development of genome-wide comparative genomics analysis,and constructing pangenomes and identifying structural variations(SVs)are becoming the frontier of genomics.Comparative genomics is of critical importance for determining the gene function and the evolutionary basis of traits.
基金the National Key Research and Development Program of China(2018YFD1000101)Hubei Provincial Natural Science Foundation of China(2021CFA017 and 2019CFA014)the National Natural ScienceFoundationof China(32001998).
文摘Dear Editor,The genus Citrus comprises more than 30 species worldwide(Swingle,1943).However,citrus genetics and traditional breeding are hindered due to asexual reproduction,long generation time,and empirical utilization of the germplasm.The whole-genome information of different citrus species accelerates the genetic studies and improves the breeding efficiency by high-density markers.