Asian lotus(Nelumbo nucifera Gaertn.)is an aquatic plant with ornamental,cultural,economic,and ecological values.China has abundant germplasm resources of Asian lotus.However,in many areas,the wild Asian lotuses have ...Asian lotus(Nelumbo nucifera Gaertn.)is an aquatic plant with ornamental,cultural,economic,and ecological values.China has abundant germplasm resources of Asian lotus.However,in many areas,the wild Asian lotuses have been destroyed and the germplasms is now facing extinction.In addition,the knowledge of the genetic diversity of the wild Asian lotus in China is poor.To identify and protect the germplasms of Chinese wild Asian lotus,eleven genomic-SSR primers,three EST-SSR primers,and three chloroplast DNA primers were used to investigate the genetic diversity among 69 samples of wild Asian lotus from 25 locations in northern China.The genetic diversity of 27 samples of wild Asian lotus from southern China and other countries,the ancient Asian lotus,Asian lotus cultivars from China,and Asian-American hybrids was also compared.The genetic diversity of the wild Asian lotus from northern China was characterized as medium,and themean values of observed heterozygosity(Ho)and expected heterozygosity(He)were 0.087 and 0.552,respectively.Based on a UPGMA dendrogram and STRUCTURE analysis,the wild Asian lotus samples in northern China were divided into three groups.The wild Asian lotus samples from northern China contained 16 haplotypes.The Nei’s genetic distance between the wild Asian lotus samples from the Songhua River basin and the Liao River basin in northeastern China was relatively small,and these germplasms might be relatively primitive compared to those from other regions.This study provides essential information regarding the genetic diversity of the wild Asian lotus resources in northern China,and provides a basis for further analysis of population-level genetic evolution through high-throughput sequencing.展开更多
American lotus(Nelumbo lutea)is one of the two species in Nelumbo and has only yellow flower.Identification of total flavonoids showed wild American lotus contained almost only flavonols with quercetin 3-O-glucuronide...American lotus(Nelumbo lutea)is one of the two species in Nelumbo and has only yellow flower.Identification of total flavonoids showed wild American lotus contained almost only flavonols with quercetin 3-O-glucuronide to be the dominant pigment.The variation tendency of the total flavonol content was coincident with yellow color variation of petals during flower development.To understand the mechanism of accumulation and constituent of pigments in petals,three pivotal genes,NlFLS1,NlFLS2 and NlFLS3,which were predicted to encode flavonol synthases were isolated and characterized by analyses of basic bioinformatics,temporal and spatial expression patterns and enzymatic activity.Their temporal expression levels showed the same variation tendency,which was also consistent with the development-dependent variation of total flavonol content.Spatial expression patterns indicated the three genes should function in petals.All the three proteins were demonstrated to be bifunctional dioxygenase,possessing both flavonol synthase activity and flavanone 3-hydroxylase activity.Besides,other flavonol biosynthesis related genes were also investigated on their expression levels to give more clues on the mechanism.Substrate preferences of the three FLSs,substrate competitions between the FLSs and other flavonol biosynthesis related enzymes,and the greatly differential expression levels between F3’H(flavonoid 3-hydroxylase)and F3’5’H(flavonoid 3,5-hydroxylase)contributed to the flavonol constituent in the petals of America lotus,namely abundant quercetin-derivatives while very few kaempferol-derivatives and myricetin-derivatives.展开更多
基金funded by Shanghai Administration Bureau of Landscape and City Appearance(Grant No.G182412).
文摘Asian lotus(Nelumbo nucifera Gaertn.)is an aquatic plant with ornamental,cultural,economic,and ecological values.China has abundant germplasm resources of Asian lotus.However,in many areas,the wild Asian lotuses have been destroyed and the germplasms is now facing extinction.In addition,the knowledge of the genetic diversity of the wild Asian lotus in China is poor.To identify and protect the germplasms of Chinese wild Asian lotus,eleven genomic-SSR primers,three EST-SSR primers,and three chloroplast DNA primers were used to investigate the genetic diversity among 69 samples of wild Asian lotus from 25 locations in northern China.The genetic diversity of 27 samples of wild Asian lotus from southern China and other countries,the ancient Asian lotus,Asian lotus cultivars from China,and Asian-American hybrids was also compared.The genetic diversity of the wild Asian lotus from northern China was characterized as medium,and themean values of observed heterozygosity(Ho)and expected heterozygosity(He)were 0.087 and 0.552,respectively.Based on a UPGMA dendrogram and STRUCTURE analysis,the wild Asian lotus samples in northern China were divided into three groups.The wild Asian lotus samples from northern China contained 16 haplotypes.The Nei’s genetic distance between the wild Asian lotus samples from the Songhua River basin and the Liao River basin in northeastern China was relatively small,and these germplasms might be relatively primitive compared to those from other regions.This study provides essential information regarding the genetic diversity of the wild Asian lotus resources in northern China,and provides a basis for further analysis of population-level genetic evolution through high-throughput sequencing.
基金supported by the Biological Resources Programme,Chinese Academy of Sciences(Grant No.KFJ-BRP-007)the National Natural Science Foundation of China(Grant No.32072620)the Shanghai Landscaping Administration Bureau(Grant No.G202405,G192415,G192407,G182412)。
文摘American lotus(Nelumbo lutea)is one of the two species in Nelumbo and has only yellow flower.Identification of total flavonoids showed wild American lotus contained almost only flavonols with quercetin 3-O-glucuronide to be the dominant pigment.The variation tendency of the total flavonol content was coincident with yellow color variation of petals during flower development.To understand the mechanism of accumulation and constituent of pigments in petals,three pivotal genes,NlFLS1,NlFLS2 and NlFLS3,which were predicted to encode flavonol synthases were isolated and characterized by analyses of basic bioinformatics,temporal and spatial expression patterns and enzymatic activity.Their temporal expression levels showed the same variation tendency,which was also consistent with the development-dependent variation of total flavonol content.Spatial expression patterns indicated the three genes should function in petals.All the three proteins were demonstrated to be bifunctional dioxygenase,possessing both flavonol synthase activity and flavanone 3-hydroxylase activity.Besides,other flavonol biosynthesis related genes were also investigated on their expression levels to give more clues on the mechanism.Substrate preferences of the three FLSs,substrate competitions between the FLSs and other flavonol biosynthesis related enzymes,and the greatly differential expression levels between F3’H(flavonoid 3-hydroxylase)and F3’5’H(flavonoid 3,5-hydroxylase)contributed to the flavonol constituent in the petals of America lotus,namely abundant quercetin-derivatives while very few kaempferol-derivatives and myricetin-derivatives.