Monocarpic senescence,characterized by whole-plant senescence following a single flowering phase,is widespread in seed plants,particularly in crops,determining seed harvest time and quality.However,how external and in...Monocarpic senescence,characterized by whole-plant senescence following a single flowering phase,is widespread in seed plants,particularly in crops,determining seed harvest time and quality.However,how external and internal signals are systemically integrated into monocarpic senescence remains largely unknown.Here,we report that the Arabidopsis thaliana transcription factor WRKY1 plays essential roles in multiple key steps of monocarpic senescence.WRKY1 expression is induced by age,salicylic acid(SA),and nitrogen(N)deficiency.Flowering and leaf senescence are accelerated in the WRKY1 overexpression lines but are delayed in the wrky1 mutants.The combined DNA affinity purification sequencing and RNA sequencing analyses uncover the direct target genes of WRKY1.Further studies show that WRKY1 coordinately regulates three processes in monocarpic senescence:(1)suppressing FLOWERING LOCUS C gene expression to initiate flowering,(2)inducing SA biosynthesis genes to promote leaf senescence,and(3)activating the N assimilation and transport genes to trigger N remobilization.In summary,our study reveals how one stress-responsive transcription factor,WRKY1,integrates flowering,leaf senescence,and N remobilization processes into monocarpic senescence,providing important insights into plant lifetime regulation.展开更多
WRKY is a plant-specific transcription factor(TF) involved in the regulation of many biological processes; however, its role in leaf senescence of leafy vegetables remains unknown. In the present work, a WRKY TF, term...WRKY is a plant-specific transcription factor(TF) involved in the regulation of many biological processes; however, its role in leaf senescence of leafy vegetables remains unknown. In the present work, a WRKY TF, termed Br WRKY75 was isolated from Chinese flowering cabbage [Brassica rapa L. ssp. chinensis(L.) Mokino var. utilis Tsen et Lee]. Analysis of deduced amino acid sequence and the phylogenetic tree showed that Br WRKY75 has high homology with WRKY75 from Brassica oleracea and Arabidopsis thaliana, and belongs to the II c sub-group. Sub-cellular localization and transcriptional activity analysis revealed that Br WRKY75 is a nuclear protein with transcriptional repression activity, and was up-regulated during leaf senescence. Electrophoretic mobility shift assay confirmed that Br WRKY75 directly bound to the W-box(TTGAC) cis-element. Collectively,these results provide a basis for further investigation of the transcriptional regulation of Chinese flowering cabbage leaf senescence.展开更多
Leaf senescence is controlled by a complex regulatory network in which robustness is ensured by the activity of transcription factors and epigenetic regulators.However,how these coordinate the process of leaf senescen...Leaf senescence is controlled by a complex regulatory network in which robustness is ensured by the activity of transcription factors and epigenetic regulators.However,how these coordinate the process of leaf senescence remains poorly understood.We found that WHIRLY1 interacts with Histone Deacetylase(HDA)15,a Reduced Potassium Dependence3(RPD3)/HDA1-type HDA,by using green fluorescent protein-nanotrap-mass spectrum assays.The development-dependent interaction between WHIRLY1 and HDA15 was further confirmed by bimolecular fluorescence complementation assays and co-immunoprecipitation assays in Arabidopsis.Multi-omics genome-wide transcriptome and H3K9 acetylome enrichment analysis showed that HDA15 delays leaf senescence and flowering by repressing the expression of the positive regulators of leaf senescence and flowering,such as LOX2 and LARP1 C,and reducing H3K9 ac levels at these loci;WHIRLY1 and HDA15 co-target to the region near the transcription start site of a subset of nutrient recycling-related genes(e.g.,Glutathione S-transferases 10,non-coding RNA,and photosystem II protein D1 synthesizer attenuator PDIL1-2),as well as WRKY53 and ELF4,and co-repress their expression by removing H3K9 acetylation.Our study revealed a key transcription regulatory node of nutrient recycling and senescence-associated genes involved in leaf senescence and flowering via the recruitment of HDA15 by the single-stranded DNA/RNA-binding protein WHIRLY1.展开更多
Ethylene regulates multiple physiological processes in cotton (Gossypium hirsutum L.) ranging from square and boll abscission to senescence. This field study investigated the effect of an ethylene inhibiting compound ...Ethylene regulates multiple physiological processes in cotton (Gossypium hirsutum L.) ranging from square and boll abscission to senescence. This field study investigated the effect of an ethylene inhibiting compound 1-methylcyclopropene (1-MCP) on boll development and the corresponding subtending leaves. The study was conducted in 2011 and 2012 at the Texas A & M Agri-LIFE Research Farm in Burleson County, TX. The study consisted of two rates of 1-MCP (0 and 10 g a.i. ha-1) applied at one and two weeks after first flower. Boll development and subtending leaves were studied on the tagged flowers during the growing season. 1-MCP treatment increased cotton boll weight at 20 days after flowering. This study showed that 1-MCP-treated subtending leaves exhibited decreased membrane damage and lipid peroxidation, and higher chlorophyll content and photosynthetic efficiency at 20 to 30 days after flowering. The healthier state of subtending leaves should have provided more carbohydrates for the fruits which could partially explain the reason for the increased boll weight. However, this beneficial effect of 1-MCP did not last to the end of the growing season and failed to result in a yield increase ultimately. Multiple applications or extending effective duration of 1-MCP is desirable to enhance the activity of 1-MCP to make a significant difference in cotton yield.展开更多
基金the Zhejiang Provincial Natural Science Foundation of China(grant LZ23C020001 to K.Z.)the National Natural Science Foundation of China(grant 31670277 to K.Z.).
文摘Monocarpic senescence,characterized by whole-plant senescence following a single flowering phase,is widespread in seed plants,particularly in crops,determining seed harvest time and quality.However,how external and internal signals are systemically integrated into monocarpic senescence remains largely unknown.Here,we report that the Arabidopsis thaliana transcription factor WRKY1 plays essential roles in multiple key steps of monocarpic senescence.WRKY1 expression is induced by age,salicylic acid(SA),and nitrogen(N)deficiency.Flowering and leaf senescence are accelerated in the WRKY1 overexpression lines but are delayed in the wrky1 mutants.The combined DNA affinity purification sequencing and RNA sequencing analyses uncover the direct target genes of WRKY1.Further studies show that WRKY1 coordinately regulates three processes in monocarpic senescence:(1)suppressing FLOWERING LOCUS C gene expression to initiate flowering,(2)inducing SA biosynthesis genes to promote leaf senescence,and(3)activating the N assimilation and transport genes to trigger N remobilization.In summary,our study reveals how one stress-responsive transcription factor,WRKY1,integrates flowering,leaf senescence,and N remobilization processes into monocarpic senescence,providing important insights into plant lifetime regulation.
基金supported by the ‘The Twelfth Five-Year Plan’ National Science and Technology Support Program (2013BAD19B07)
文摘WRKY is a plant-specific transcription factor(TF) involved in the regulation of many biological processes; however, its role in leaf senescence of leafy vegetables remains unknown. In the present work, a WRKY TF, termed Br WRKY75 was isolated from Chinese flowering cabbage [Brassica rapa L. ssp. chinensis(L.) Mokino var. utilis Tsen et Lee]. Analysis of deduced amino acid sequence and the phylogenetic tree showed that Br WRKY75 has high homology with WRKY75 from Brassica oleracea and Arabidopsis thaliana, and belongs to the II c sub-group. Sub-cellular localization and transcriptional activity analysis revealed that Br WRKY75 is a nuclear protein with transcriptional repression activity, and was up-regulated during leaf senescence. Electrophoretic mobility shift assay confirmed that Br WRKY75 directly bound to the W-box(TTGAC) cis-element. Collectively,these results provide a basis for further investigation of the transcriptional regulation of Chinese flowering cabbage leaf senescence.
基金supported by the grant of National Natural Science Foundation of China(31770318,31470383)the grant of excellent PhD candidate program of Fujian Agriculture and Forestry University(324-1122yb049)+1 种基金the grant of Chinese Postdoctoral Science Foundation(2019M652232)the grant of Novel Project of Fujian Agriculture and Forestry University(KFA19048A)。
文摘Leaf senescence is controlled by a complex regulatory network in which robustness is ensured by the activity of transcription factors and epigenetic regulators.However,how these coordinate the process of leaf senescence remains poorly understood.We found that WHIRLY1 interacts with Histone Deacetylase(HDA)15,a Reduced Potassium Dependence3(RPD3)/HDA1-type HDA,by using green fluorescent protein-nanotrap-mass spectrum assays.The development-dependent interaction between WHIRLY1 and HDA15 was further confirmed by bimolecular fluorescence complementation assays and co-immunoprecipitation assays in Arabidopsis.Multi-omics genome-wide transcriptome and H3K9 acetylome enrichment analysis showed that HDA15 delays leaf senescence and flowering by repressing the expression of the positive regulators of leaf senescence and flowering,such as LOX2 and LARP1 C,and reducing H3K9 ac levels at these loci;WHIRLY1 and HDA15 co-target to the region near the transcription start site of a subset of nutrient recycling-related genes(e.g.,Glutathione S-transferases 10,non-coding RNA,and photosystem II protein D1 synthesizer attenuator PDIL1-2),as well as WRKY53 and ELF4,and co-repress their expression by removing H3K9 acetylation.Our study revealed a key transcription regulatory node of nutrient recycling and senescence-associated genes involved in leaf senescence and flowering via the recruitment of HDA15 by the single-stranded DNA/RNA-binding protein WHIRLY1.
文摘Ethylene regulates multiple physiological processes in cotton (Gossypium hirsutum L.) ranging from square and boll abscission to senescence. This field study investigated the effect of an ethylene inhibiting compound 1-methylcyclopropene (1-MCP) on boll development and the corresponding subtending leaves. The study was conducted in 2011 and 2012 at the Texas A & M Agri-LIFE Research Farm in Burleson County, TX. The study consisted of two rates of 1-MCP (0 and 10 g a.i. ha-1) applied at one and two weeks after first flower. Boll development and subtending leaves were studied on the tagged flowers during the growing season. 1-MCP treatment increased cotton boll weight at 20 days after flowering. This study showed that 1-MCP-treated subtending leaves exhibited decreased membrane damage and lipid peroxidation, and higher chlorophyll content and photosynthetic efficiency at 20 to 30 days after flowering. The healthier state of subtending leaves should have provided more carbohydrates for the fruits which could partially explain the reason for the increased boll weight. However, this beneficial effect of 1-MCP did not last to the end of the growing season and failed to result in a yield increase ultimately. Multiple applications or extending effective duration of 1-MCP is desirable to enhance the activity of 1-MCP to make a significant difference in cotton yield.
