Rice is a poor source of folate,an essential micronutrient for the body.Biofortification offers an effective way to enhance the folate content of rice and alleviate folate deficiencies in humans.In this study,we confi...Rice is a poor source of folate,an essential micronutrient for the body.Biofortification offers an effective way to enhance the folate content of rice and alleviate folate deficiencies in humans.In this study,we confirmed that OsADCS and OsGTPCHI,encoding the initial enzymes necessary for folate synthesis,positively regulate folate accumulation in knockout mutants of both japonica and indica rice backgrounds.The folate content in the low-folate japonica variety was slightly increased by the expression of the indica alleles driven by the endosperm-specific promoter.We further obtained co-expression lines by stacking OsADCS and OsGTPCHI genes;the folate accumulation in brown rice and polished rice reached 5.65μg/g and 2.95μg/g,respectively,representing 37.9-fold and 26.5-fold increases compared with the wild type.Transcriptomic analysis of rice grains from six transgenic lines showed that folate changes affected biological pathways involved in the synthesis and metabolism of rice seed storage substances,while the expression of other folate synthesis genes was weakly regulated.In addition,we identified Aus rice as a high-folate germplasm carrying superior haplotypes of OsADCS and OsGTPCHI through natural variation.This study provides an alternative and effective complementary strategy for rice biofortification,promoting the rational combination of metabolic engineering and conventional breeding to breed high-folate varieties.展开更多
Amylose content(AC)is the key determinant of eating and cooking quality(ECQ)of rice.The major Wxa allele of granule-bound starch synthase I(GBSS I)in indica rice produces higher AC,making rice hard and dry after cooki...Amylose content(AC)is the key determinant of eating and cooking quality(ECQ)of rice.The major Wxa allele of granule-bound starch synthase I(GBSS I)in indica rice produces higher AC,making rice hard and dry after cooking.Recent work has improved ECQ of japonica rice via clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9(CRISPR/Cas9)or cytosine base editing(CBE)techniques.展开更多
OsPho1 in Zhonghua 11(ZH11)was edited using the clustered regularly interspaced short palindromic repeatsassociated endonuclease 9(CRISPR/Cas9)system.Two homozygous T1 mutants(cr-pho1-34 and cr-pho1-37)displayed a cha...OsPho1 in Zhonghua 11(ZH11)was edited using the clustered regularly interspaced short palindromic repeatsassociated endonuclease 9(CRISPR/Cas9)system.Two homozygous T1 mutants(cr-pho1-34 and cr-pho1-37)displayed a chalky endosperm with a white core,which significantly decreased 1000-grain weight.In addition,many rounded starch granules and abnormal amyloplasts were present in the central region of mutant endosperm cells with increased amylose and lipid contents,decreased total protein content,and altered physicochemical properties of starch.The OsPho1 protein is localized in chloroplasts,and quantitative real-time PCR(qRT-PCR)andβ-glucuronidase(GUS)staining indicated that OsPho1 was highly expressed in seeds at 5 d after fertilization(DAF).OsPho1 mutations displayed close relationships with plastidial phosphoglucomutase and ADPGlc pyrophosphorylase based onα-D-glucose-1P at different temperatures.Moreover,the expressions of starch metabolismrelated genes were also altered in the mutant,and the overexpression of OsPho1 may cause grain chalkiness.展开更多
NRL3 is essential for the growth and development of rice leaves.In this study,we found that the loss function of NRL3 also delayed heading date under natural long daylight and short daylight conditions.The yeast two-h...NRL3 is essential for the growth and development of rice leaves.In this study,we found that the loss function of NRL3 also delayed heading date under natural long daylight and short daylight conditions.The yeast two-hybrid and the bimolecular fluorescence complementation proved that NRL3interacts with OsK4,a Snf1-related kinase.OsK4 localized to the nucleus and expressed in various rice tissues.The rhythmic expression pattern of Os K4 was similar to NRL3 under long daylight and short daylight conditions.Knock-out mutants of Os K4 exhibited early heading under long daylight conditions,indicating that it acts as a negative regulator of heading date in rice.Interestingly,the OsK4 mutant under the nrl3 mutant background rescued the late heading phenotype of nrl3 under long daylight conditions,suggesting that Os K4 functions downstream of NRL3.Moreover,both NRL3 and Os K4 controlled heading date through regulating the expression of Hd3a and RFT1 genes.These findings shed light on the heading date regulation in rice and provide a sound theoretical base to improve regional adaptability of rice.展开更多
基金supported by the Central Public-Interest Scientific Institution Basal Research Fund,China(Grant No.CPSIBRF-CNRRI-202403)。
文摘Rice is a poor source of folate,an essential micronutrient for the body.Biofortification offers an effective way to enhance the folate content of rice and alleviate folate deficiencies in humans.In this study,we confirmed that OsADCS and OsGTPCHI,encoding the initial enzymes necessary for folate synthesis,positively regulate folate accumulation in knockout mutants of both japonica and indica rice backgrounds.The folate content in the low-folate japonica variety was slightly increased by the expression of the indica alleles driven by the endosperm-specific promoter.We further obtained co-expression lines by stacking OsADCS and OsGTPCHI genes;the folate accumulation in brown rice and polished rice reached 5.65μg/g and 2.95μg/g,respectively,representing 37.9-fold and 26.5-fold increases compared with the wild type.Transcriptomic analysis of rice grains from six transgenic lines showed that folate changes affected biological pathways involved in the synthesis and metabolism of rice seed storage substances,while the expression of other folate synthesis genes was weakly regulated.In addition,we identified Aus rice as a high-folate germplasm carrying superior haplotypes of OsADCS and OsGTPCHI through natural variation.This study provides an alternative and effective complementary strategy for rice biofortification,promoting the rational combination of metabolic engineering and conventional breeding to breed high-folate varieties.
基金supported by the China National Key Research and Development Program(Grant No.2020YFE0202300)the Central Public-Interest Scientific Institution Basal Research Fund of China(Grant No&Y2020PT07 and Y2020YJ09)the International Science&Technology Innovation Program of Chinese Academy of Agricultural Sciences,China(Grant No.CAAS-ZDRW202109).
文摘Amylose content(AC)is the key determinant of eating and cooking quality(ECQ)of rice.The major Wxa allele of granule-bound starch synthase I(GBSS I)in indica rice produces higher AC,making rice hard and dry after cooking.Recent work has improved ECQ of japonica rice via clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9(CRISPR/Cas9)or cytosine base editing(CBE)techniques.
基金supported by the National Science Foundation of China(Grant No.3197150429).
文摘OsPho1 in Zhonghua 11(ZH11)was edited using the clustered regularly interspaced short palindromic repeatsassociated endonuclease 9(CRISPR/Cas9)system.Two homozygous T1 mutants(cr-pho1-34 and cr-pho1-37)displayed a chalky endosperm with a white core,which significantly decreased 1000-grain weight.In addition,many rounded starch granules and abnormal amyloplasts were present in the central region of mutant endosperm cells with increased amylose and lipid contents,decreased total protein content,and altered physicochemical properties of starch.The OsPho1 protein is localized in chloroplasts,and quantitative real-time PCR(qRT-PCR)andβ-glucuronidase(GUS)staining indicated that OsPho1 was highly expressed in seeds at 5 d after fertilization(DAF).OsPho1 mutations displayed close relationships with plastidial phosphoglucomutase and ADPGlc pyrophosphorylase based onα-D-glucose-1P at different temperatures.Moreover,the expressions of starch metabolismrelated genes were also altered in the mutant,and the overexpression of OsPho1 may cause grain chalkiness.
基金supported by the China National Natural Science Foundation(Grant No.31871597)the Key Research and Development Program of Zhejiang Province,China(Grant No.2021C02063-2)+2 种基金the Key Research and Development Program of China National Rice Research Institute(Grant No.CNRRI-2020-02)the Science and Technology Project of Jiangxi Provincial Department of Education,China(Grant No.GJJ180217)the Project supported by Jiangxi Youth Science Foundation,China(Grant No.20202BAB215001)。
文摘NRL3 is essential for the growth and development of rice leaves.In this study,we found that the loss function of NRL3 also delayed heading date under natural long daylight and short daylight conditions.The yeast two-hybrid and the bimolecular fluorescence complementation proved that NRL3interacts with OsK4,a Snf1-related kinase.OsK4 localized to the nucleus and expressed in various rice tissues.The rhythmic expression pattern of Os K4 was similar to NRL3 under long daylight and short daylight conditions.Knock-out mutants of Os K4 exhibited early heading under long daylight conditions,indicating that it acts as a negative regulator of heading date in rice.Interestingly,the OsK4 mutant under the nrl3 mutant background rescued the late heading phenotype of nrl3 under long daylight conditions,suggesting that Os K4 functions downstream of NRL3.Moreover,both NRL3 and Os K4 controlled heading date through regulating the expression of Hd3a and RFT1 genes.These findings shed light on the heading date regulation in rice and provide a sound theoretical base to improve regional adaptability of rice.
