Lutein is an oxygen-containing carotenoid synthesized in plant chloroplasts and chromoplasts.It plays an indispensable role in promoting plant growth and maintaining eye health in humans.The rate-limiting step of lute...Lutein is an oxygen-containing carotenoid synthesized in plant chloroplasts and chromoplasts.It plays an indispensable role in promoting plant growth and maintaining eye health in humans.The rate-limiting step of lutein biosynthesis is catalyzed by the lycopeneε-cyclase enzyme(LCYE).Although great progress has been made in the identification of transcription factors involved in the lutein biosynthetic pathway,many systematic molecular mechanisms remain to be elucidated.Here,using co-expression analysis,we identified a gene,G2-LIKE CAROTENOID REGULATOR(SlGCR),encoding a GARP G2-like transcription factor,as the potential regulator of SlLCYE in tomato.Silencing of SlGCR reduced the expression of carotenoid biosynthetic genes and the accumulation of carotenoids in tomato leaves.By contrast,overexpression of SlGCR in tomato fruit significantly increased the expression of relevant genes and enhanced the accumulation of carotenoids.SlGCR can directly bind to the SlLCYE promoter and activate its expression.In addition,we also discovered that expression of SlGCR was negatively regulated by the master regulator SlRIN,thereby inhibiting lutein synthesis during tomato fruit ripening.Taken together,we identified SlGCR as a novel regulator involved in tomato lutein biosynthesis,elucidated the regulatory mechanism,and provided a potential tool for tomato lutein metabolic engineering.展开更多
Stomata play critical roles in gas exchange and immunity to pathogens.While many genes regulating early stomatal development up to the production of young guard cells(GCs)have been identified in Arabidopsis,much less ...Stomata play critical roles in gas exchange and immunity to pathogens.While many genes regulating early stomatal development up to the production of young guard cells(GCs)have been identified in Arabidopsis,much less is known about how young GCs develop into mature functional stomata.Here we perform a maturomics study on stomata,with“maturomics”defined as omics analysis of the maturation process of a tissue or organ.We develop an integrative scheme to analyze three public stomata-related single-cell RNAseq datasets and identify a list of 586 genes that are specifically up-regulated in all three datasets during stomatal maturation and function formation.The list,termed sc_586,is enriched with known regulators of stomatal maturation and functions.To validate the reliability of the dataset,we selected two candidate G2-like transcription factor genes,MYS1 and MYS2,to investigate their roles in stomata.These two genes redundantly regulate the size and hoop rigidity of mature GCs,and the mys1 mys2 double mutants cause mature GCs with severe defects in regulating their stomatal apertures.Taken together,our results provide a valuable list of genes for studying GC maturation and function formation.展开更多
Phosphate （Pi） deficiency causes dramatic root system architecture （RSA） changes in higher plants. Here we report that overexpression of HRS1 leads to enhanced sensitivity to low Pi-elicited inhibition of primary ...Phosphate （Pi） deficiency causes dramatic root system architecture （RSA） changes in higher plants. Here we report that overexpression of HRS1 leads to enhanced sensitivity to low Pi-elicited inhibition of primary root growth in Arabidopsis thaliana seedlings. Bioinformatic investigations uncovered that HRS1 and its six homologs encode putative G2-like transcription factors in Arabidopsis. Analysis of promoter：：GUS reporter lines revealed that HRS1 transcripts were present mainly in the root hair region and root hair cells under Pi-sufficient conditions. Pi deprivation increased HRS1 expression level and expanded its expression domain. Although HRS1 knockout mutant did not differ from wild type （WT） control irrespective of Pi status, its overexpression lines were significantly more susceptible to low Pi-elicited primary root shortening. In both WT and HRS1 overexpression seedlings, low Pi-induced primary root shortening was accompanied by enhanced root hair cell differentiation, but this enhancement occurred to a greater extent in the latter genotype. Collectively, our data suggest that HRS1 may be involved in the modulation of primary root and root hair growth in Pi-deprived Arabidopsis seedlings, and provide useful clues for further research into the function of HRS1 and its homologs and the mechanisms behind RSA changes under Pi-deficient conditions.展开更多
基金funded by the Sichuan Science and Technology Program(2021YFYZ0027)the National Natural Science Foundation of China(32170266)+1 种基金the Institutional Research Fund of Sichuan University(2020SCUNL106)the Fundamental Research Funds for the Central Universities(SCU2022D003).We acknowledge the Mass Spectrometry Core Facility in the College of Life Sciences,Sichuan University,for assistance in metabolic analysis.
文摘Lutein is an oxygen-containing carotenoid synthesized in plant chloroplasts and chromoplasts.It plays an indispensable role in promoting plant growth and maintaining eye health in humans.The rate-limiting step of lutein biosynthesis is catalyzed by the lycopeneε-cyclase enzyme(LCYE).Although great progress has been made in the identification of transcription factors involved in the lutein biosynthetic pathway,many systematic molecular mechanisms remain to be elucidated.Here,using co-expression analysis,we identified a gene,G2-LIKE CAROTENOID REGULATOR(SlGCR),encoding a GARP G2-like transcription factor,as the potential regulator of SlLCYE in tomato.Silencing of SlGCR reduced the expression of carotenoid biosynthetic genes and the accumulation of carotenoids in tomato leaves.By contrast,overexpression of SlGCR in tomato fruit significantly increased the expression of relevant genes and enhanced the accumulation of carotenoids.SlGCR can directly bind to the SlLCYE promoter and activate its expression.In addition,we also discovered that expression of SlGCR was negatively regulated by the master regulator SlRIN,thereby inhibiting lutein synthesis during tomato fruit ripening.Taken together,we identified SlGCR as a novel regulator involved in tomato lutein biosynthesis,elucidated the regulatory mechanism,and provided a potential tool for tomato lutein metabolic engineering.
基金supported by grants from the Strategic Priority Research Program of the Chinese Academy of Science(XDA24010303)the National Natural Science Foundation of China(31770268)+1 种基金the Fundamental Research Funds for the Central Universities(WK2070000091)the University of Science and Technology of China(Start-up fund to S.M.)。
文摘Stomata play critical roles in gas exchange and immunity to pathogens.While many genes regulating early stomatal development up to the production of young guard cells(GCs)have been identified in Arabidopsis,much less is known about how young GCs develop into mature functional stomata.Here we perform a maturomics study on stomata,with“maturomics”defined as omics analysis of the maturation process of a tissue or organ.We develop an integrative scheme to analyze three public stomata-related single-cell RNAseq datasets and identify a list of 586 genes that are specifically up-regulated in all three datasets during stomatal maturation and function formation.The list,termed sc_586,is enriched with known regulators of stomatal maturation and functions.To validate the reliability of the dataset,we selected two candidate G2-like transcription factor genes,MYS1 and MYS2,to investigate their roles in stomata.These two genes redundantly regulate the size and hoop rigidity of mature GCs,and the mys1 mys2 double mutants cause mature GCs with severe defects in regulating their stomatal apertures.Taken together,our results provide a valuable list of genes for studying GC maturation and function formation.
基金Supported by the National Natural Science Foundation of China(30521001)the Ministry of Science and Technology of China(2005CB120904).
文摘Phosphate （Pi） deficiency causes dramatic root system architecture （RSA） changes in higher plants. Here we report that overexpression of HRS1 leads to enhanced sensitivity to low Pi-elicited inhibition of primary root growth in Arabidopsis thaliana seedlings. Bioinformatic investigations uncovered that HRS1 and its six homologs encode putative G2-like transcription factors in Arabidopsis. Analysis of promoter：：GUS reporter lines revealed that HRS1 transcripts were present mainly in the root hair region and root hair cells under Pi-sufficient conditions. Pi deprivation increased HRS1 expression level and expanded its expression domain. Although HRS1 knockout mutant did not differ from wild type （WT） control irrespective of Pi status, its overexpression lines were significantly more susceptible to low Pi-elicited primary root shortening. In both WT and HRS1 overexpression seedlings, low Pi-induced primary root shortening was accompanied by enhanced root hair cell differentiation, but this enhancement occurred to a greater extent in the latter genotype. Collectively, our data suggest that HRS1 may be involved in the modulation of primary root and root hair growth in Pi-deprived Arabidopsis seedlings, and provide useful clues for further research into the function of HRS1 and its homologs and the mechanisms behind RSA changes under Pi-deficient conditions.
