It is known that the high level of sugar including glucose suppresses seed germination through ABA signal.ABI5 is an essential component to mediate ABA-dependent seed germination inhibition,but underlying mechanism ne...It is known that the high level of sugar including glucose suppresses seed germination through ABA signal.ABI5 is an essential component to mediate ABA-dependent seed germination inhibition,but underlying mechanism needs more investigation.Previous study demonstrated the PIF4 activated the expression of ABI5 to suppress seed germination in darkness.Here we reported that PIF4 also mediated the seed germination inhibition through ABI5 under high concentration of glucose treatment.Furthermore,we found that PIF4 interacted with PAP1,the central factor to control anthocyanin biosynthesis.Such interaction was confirmed in vitro and in planta.Biochemical and physiological analysis revealed that PAP1 bond the promoter of ABI5 to suppress its expression,thus enhanced seed germination under high concentration of glucose treatment.Specially,PAP1 competed with PIF4 to antagonize the activation of PIF4 on ABI5 expression,thus promoted seed germination under high glucose treatment.Given these,we uncover a novel role for PIF4 and PAP1 in controlling seed germination under high glucose treatment,and reveal their antagonistic mechanism by which coordinates ABI5 expression to control seed germination in response to the glucose signal.展开更多
Anthocyanins play diverse roles in plant physiology and stress adaptation.In Arabidopsis,the MYB–bHLH–WD40(MBW)complex has a crucial role in the regulation of anthocyanin synthesis.Here,we report that the R2R3-MYB t...Anthocyanins play diverse roles in plant physiology and stress adaptation.In Arabidopsis,the MYB–bHLH–WD40(MBW)complex has a crucial role in the regulation of anthocyanin synthesis.Here,we report that the R2R3-MYB transcription factor MYB30 and the ubiquitin E3 ligase RHA2b participate in anthocyanin biosynthesis through regulation of the MBW complex.MYB30 was found to negatively regulate sucrose-induced anthocyanin biosynthesis in Arabidopsis seedlings.Expression of multiple genes involved inflavo-noid or anthocyanin biosynthesis was affected in the myb30 mutant,and MYB30 directly repressed the expression of MYB75,which encodes a core component of the MBW complex,by binding to its promoter.Moreover,MYB30 physically interacted with MYB75 to inhibit its activity by repressing MBW complex as-sembly.In addition,sucrose treatment signicantly promoted MYB30 degradation via the action of RHA2b.The ubiquitination and degradation of MYB30 were signicantly attenuated in the rha2b mutant un-der high-sucrose treatment,and further analysis showed that MYB75 directly promoted RHA2b expression in response to high sucrose.Our work thus reveals an anthocyanin biosynthetic regulatory module,RHA2b–MYB30,that controls the function of the MBW complex via MYB75.The repression of MYB75 by MYB30 is released by MYB75-induced RHA2b expression,thus ensuring the self-activation of MYB75 when anthocy-anin synthesis is needed.展开更多
Anthocyanins are important natural plant pigments and play diverse roles in plant growth and adaptation.Anthocyanins function as screens to protect photosynthetic tissues from photoinhibition.However,the regulatory me...Anthocyanins are important natural plant pigments and play diverse roles in plant growth and adaptation.Anthocyanins function as screens to protect photosynthetic tissues from photoinhibition.However,the regulatory mechanisms underlying the biosynthesis and spatial accumulation pattern of anthocyanins remain some unresolved issues.Here,we demonstrate that the GARP-type transcription factor GOLDEN2-LIKE 1(GLK1)functions as a positive factor in anthocyanin accumulation.GLK1 enhances the transcriptional activation activities of MYB75,MYB90,and MYB113 via direct proteinprotein interactions to increase the expression of anthocyanin-specific biosynthetic genes.Anthocyanins accumulate in an acropetal manner in Arabidopsis.We also found that the expression pattern of GLK1 overall mimicked the accumulation pattern of anthocyanin from the base of the main stem to the shoot apex.Based on these findings,we established a working model for the role of GLK1 in anthocyanin accumulation and propose that GLK1mediates the spatial distribution pattern of anthocyanins by affecting the transcriptional activation activities of MYB75,MYB90,and MYB113.展开更多
基金funded by the National Natural Science Foundation of China(Grant No.31970289).
文摘It is known that the high level of sugar including glucose suppresses seed germination through ABA signal.ABI5 is an essential component to mediate ABA-dependent seed germination inhibition,but underlying mechanism needs more investigation.Previous study demonstrated the PIF4 activated the expression of ABI5 to suppress seed germination in darkness.Here we reported that PIF4 also mediated the seed germination inhibition through ABI5 under high concentration of glucose treatment.Furthermore,we found that PIF4 interacted with PAP1,the central factor to control anthocyanin biosynthesis.Such interaction was confirmed in vitro and in planta.Biochemical and physiological analysis revealed that PAP1 bond the promoter of ABI5 to suppress its expression,thus enhanced seed germination under high concentration of glucose treatment.Specially,PAP1 competed with PIF4 to antagonize the activation of PIF4 on ABI5 expression,thus promoted seed germination under high glucose treatment.Given these,we uncover a novel role for PIF4 and PAP1 in controlling seed germination under high glucose treatment,and reveal their antagonistic mechanism by which coordinates ABI5 expression to control seed germination in response to the glucose signal.
基金supported by the National Natural Science Foundation of China (grants 32170295 and 31870241 to H.Z.)the China Postdoctoral Science Foundation (grant 2023M730776 to J.H.)the Institutional Research Fund of Sichuan University (grant 2020SCUNL212 to H.L.).
文摘Anthocyanins play diverse roles in plant physiology and stress adaptation.In Arabidopsis,the MYB–bHLH–WD40(MBW)complex has a crucial role in the regulation of anthocyanin synthesis.Here,we report that the R2R3-MYB transcription factor MYB30 and the ubiquitin E3 ligase RHA2b participate in anthocyanin biosynthesis through regulation of the MBW complex.MYB30 was found to negatively regulate sucrose-induced anthocyanin biosynthesis in Arabidopsis seedlings.Expression of multiple genes involved inflavo-noid or anthocyanin biosynthesis was affected in the myb30 mutant,and MYB30 directly repressed the expression of MYB75,which encodes a core component of the MBW complex,by binding to its promoter.Moreover,MYB30 physically interacted with MYB75 to inhibit its activity by repressing MBW complex as-sembly.In addition,sucrose treatment signicantly promoted MYB30 degradation via the action of RHA2b.The ubiquitination and degradation of MYB30 were signicantly attenuated in the rha2b mutant un-der high-sucrose treatment,and further analysis showed that MYB75 directly promoted RHA2b expression in response to high sucrose.Our work thus reveals an anthocyanin biosynthetic regulatory module,RHA2b–MYB30,that controls the function of the MBW complex via MYB75.The repression of MYB75 by MYB30 is released by MYB75-induced RHA2b expression,thus ensuring the self-activation of MYB75 when anthocy-anin synthesis is needed.
基金supported by grants from the National Natural Science Foundation of China(31970263 to HL32070213 to DZ)+4 种基金the Sichuan Science and Technology Program(2022JDRC0032)Open Project Funding of the State Key Laboratory of Crop Stress Adaptation and Improvementthe Institutional Research Fund of Sichuan University(2020SCUNL212)the Fundamental Research Funds for the Central Universities(SCU2020D003)the Sichuan Forage Innovation Team Program。
文摘Anthocyanins are important natural plant pigments and play diverse roles in plant growth and adaptation.Anthocyanins function as screens to protect photosynthetic tissues from photoinhibition.However,the regulatory mechanisms underlying the biosynthesis and spatial accumulation pattern of anthocyanins remain some unresolved issues.Here,we demonstrate that the GARP-type transcription factor GOLDEN2-LIKE 1(GLK1)functions as a positive factor in anthocyanin accumulation.GLK1 enhances the transcriptional activation activities of MYB75,MYB90,and MYB113 via direct proteinprotein interactions to increase the expression of anthocyanin-specific biosynthetic genes.Anthocyanins accumulate in an acropetal manner in Arabidopsis.We also found that the expression pattern of GLK1 overall mimicked the accumulation pattern of anthocyanin from the base of the main stem to the shoot apex.Based on these findings,we established a working model for the role of GLK1 in anthocyanin accumulation and propose that GLK1mediates the spatial distribution pattern of anthocyanins by affecting the transcriptional activation activities of MYB75,MYB90,and MYB113.
