Drought stress impairs plant growth and other physiological functions. MeHDZ14, a homeodomainleucine zipper I transcription factor, is strongly induced by drought stress in various cassava cultivars.However, the role ...Drought stress impairs plant growth and other physiological functions. MeHDZ14, a homeodomainleucine zipper I transcription factor, is strongly induced by drought stress in various cassava cultivars.However, the role of MeHDZ14 in cassava growth regulation has remained unclear. Here we report that MeHDZ14 affected plant height, such that a dwarf phenotype and altered internode elongation were observed in transgenic cassava lines. MeHDZ14 was found to negatively regulate the biosynthesis of lignin. Its overexpression resulted in abaxially rolled leaves. The morphogenesis of leaf epidermal cells was inhibited by overexpression of MeHDZ14, with decreased auxin and gibberellin and increased cytokinin contents. MeHDZ14 was found to regulate many drought-responsive genes, including genes involved in cell wall synthesis and expansion. MeHDZ14 bound to the promoter of caffeic acid 3-Omethyltransferase 1(MeCOMT1), acting as a transcriptional repressor of genes involved in cell wall development. MeHDZ14 appears to act as a negative regulator of internode elongation and epidermal cell morphogenesis during cassava leaf development.展开更多
In this study, we analyze the binding of nuclear proteins isolated from the hydroxyurea (Hu)-induced and uninduced HEL cells to the DNasel hypersensitive sites Ⅲ (HS3 -14991 --14716 bp) and Ⅳ(HS4 -18586-18306 bp) in...In this study, we analyze the binding of nuclear proteins isolated from the hydroxyurea (Hu)-induced and uninduced HEL cells to the DNasel hypersensitive sites Ⅲ (HS3 -14991 --14716 bp) and Ⅳ(HS4 -18586-18306 bp) in the human p-globin gene locus control region (LCR). Using Western blot assay, we demonstrate that GATA-1 transcription factor in HEL cells is increased following the induction of Hu, while GATA-2 transcription factor is decreased. Based on both the competition EMSA and the Western blot assay, our data reveal that the nuclear protein isolated from the uninduced HEL cells, which can bind to the HS3 and HS4 core DNA sequences, is mainly GATA-2; however, the nuclear proteins isolated from the Hu-induced HEL cells, which can bind to the HS3 and HS4 core DNA sequences, are mainly GATA-1 and GATA-X (a kind of unknown GATA factor). These results suggest that the erythroid specific transcription factors (GATA-1 and GATA-2) in the Hu-induced and uninduced HEL cells can selectively bind to the HS3展开更多
Homeobox 1 in Malusxdomestica （MdHB-1） is a transcription factor that belongs to homeodomain-leucine zipper I （HD-Zip I） protein subfamily. According to previous reports, MdHB-1 could regulate ethylene synthesis b...Homeobox 1 in Malusxdomestica （MdHB-1） is a transcription factor that belongs to homeodomain-leucine zipper I （HD-Zip I） protein subfamily. According to previous reports, MdHB-1 could regulate ethylene synthesis by binding with the MdAC01 promoter, but other functions of MdHB-1 are still unknown. To reveal more clues concerning the characters of the MdHB-1 gene promoter and the functions of MdHB-1, the promoter region of MdHB-1 was cloned from the Royal Gala apple genome and recombined with the 13-glucuronidase （GUS） gene in this study. This research was conducted in Nicotiana tabacum and supported by Agrobacterium-mediated transient transformation and bioinformatics analysis. Deletion analysis of the MdHB-1 promoter showed that the GUS gene could be activated by serially deleted promoters, and the activity promoted by 680 nucleotides （nt） was the lowest. The region, which is 266 nt upstream of the initiation code （ATG）, was effective for GUS expression. Meanwhile, the activity of the MdHB-1 promoter （-1 057 nt）, which was stronger than MdHB-1 promoter （-1 057 to -266 nt） and lack the 5＂-untranslated region （5＂-UTR）, showed that 5＂-UTR may have a positive effect on gene transcription. After the sequence analysis, the cis-acting elements that respond to hormones and environmental stresses were identified in the promoter region. The MdHB-1 promoter （1 057 nt） activity in Nicotiana tabacum was positively induced by ethrel and darkness, and it was suppressed by gibberellic acid （GA）, whereas abscisic acid （ABA）, salicylic acid （SA）, wounding, and Pseudomonas syringae pv. tomato （DC3000） treatments revealed a slight auxo-action. These results reveal that the MdHB-1 promoter receive internal or external signals, and MdHB-1 may refer to many biological activities in apple, such as its stress response, development, and ripening.展开更多
The zinc finger motif was used as a vehicle for the initial discovery of Ikaros in the context of T-cell differentiation and has been central to all subsequent analyses of Ikaros function.The Ikaros gene is alternatel...The zinc finger motif was used as a vehicle for the initial discovery of Ikaros in the context of T-cell differentiation and has been central to all subsequent analyses of Ikaros function.The Ikaros gene is alternately spliced to produce several isoforms that confer diversity of function and consequently have complicated analysis of the function of Ikaros in vivo.Key features of Ikaros in vivo function are associated with six C2H2 zinc fingers;four of which are alternately incorporated in the production of the various Ikaros isoforms.Although no complete structures are available for the Ikaros protein or any of its family members,considerable evidence has accumulated about the structure of zinc fingers and the role that this structure plays in the functions of the Ikaros family of proteins.This review summarizes the structural aspects of Ikaros zinc fingers,individually,and in tandem to provide a structural context for Ikaros function and to provide a structural basis to inform the design of future experiments with Ikaros and its family members.展开更多
Transcription factors play key roles in plant development and stress responses through their interaction with cis-elements and/or other transcription factors. Homeodomain associated leucine zipper proteins (HD-Zip) co...Transcription factors play key roles in plant development and stress responses through their interaction with cis-elements and/or other transcription factors. Homeodomain associated leucine zipper proteins (HD-Zip) constitute a family of transcription factors that are characterized by the presence of a DNA-binding domain closely linked with leucine zipper motif functioning in dimer formation. This type of association is unique to plants and considered as an excellent candidate to activate developmental responses to altering environmental conditions. Cotton is the most important fiber plant with a lot of local and commercial uses in the world. HD-Zip proteins not only have key roles in different stages of vascular and inter-fascicular fiber differentiation of cotton but also are suggested to have an important role against abiotic stress that is one of the key factors limiting cotton productivity. Plants have developed various strategies to manage stress conditions through a combination of metabolic, physiological and morphological adaptations. These adaptive changes rely largely on alterations in gene expression. Therefore, transcriptional regulators play a crucial role in stress tolerance. Being a transcription factor HD-Zip might be a useful target for genetic engineering to generate multiple stress tolerance in susceptible plants. In the following chapter, we discussed how the HD-Zip proteins would play a useful role for cotton development both in fiber production and stress adaptation.展开更多
It is of great importance to better understand how trees regulate nitrogen(N) uptake under N deficiency conditions which severely challenge afforestation practices, yet the underlying molecular mechanisms have not bee...It is of great importance to better understand how trees regulate nitrogen(N) uptake under N deficiency conditions which severely challenge afforestation practices, yet the underlying molecular mechanisms have not been well elucidated. Here,we functionally characterized PuHox52, a Populus ussuriensis HD-ZIP transcription factor, whose overexpression greatly enhanced nutrient uptake and plant growth under N deficiency. We first conducted an RNA sequencing experiment to obtain root transcriptome using PuHox52-overexpression lines of P. ussuriensis under low N treatment. We then performed multiple genetic and phenotypic analyses to identify key target genes of PuHox52 and validated how they acted against N deficiency under PuHox52 regulation.PuHox52 was specifically induced in roots by N deficiency, and overexpression of PuHox52promoted N uptake, plant growth, and root development. We demonstrated that several nitrate-responsive genes(PuNRT1.1, PuNRT2.4,PuCLC-b, PuNIA2, PuNIR1, and PuNLP1),phosphate-responsive genes(PuPHL1A and PuPHL1B), and an iron transporter gene(PuIRT1) were substantiated to be direct targets of PuHox52. Among them, PuNRT1.1, PuPHL1A/B, and PuIRT1 were upregulated to relatively higher levels during PuHox52-mediated responses against N deficiency in PuHox52-overexpression lines compared to WT. Our study revealed a novel regulatory mechanism underlying root adaption to N deficiency where PuHox52 modulated a coordinated uptake of nitrate, phosphate, and iron through 'PuHox52-PuNRT1.1', 'PuHox52-PuPHL1A/PuPHL1B', and'PuHox52-PuIRT1' regulatory relationships in poplar roots.展开更多
基金supported by the China Agriculture Research System (CARS11-HNCX)the Major Science and Technology Plan of Hainan Province (ZDKJ2021012)+3 种基金the Central Public-interest Scientific Institution Basal Research Fund for Chinese Academy of Tropical Agricultural Sciences (1630052022008)the National Key Research and Development Program of China (2018YFD1000501)the National Natural Science Foundation of China (31501378)the Hainan Yazhou Bay Seed Lab (B21HJ0303)。
文摘Drought stress impairs plant growth and other physiological functions. MeHDZ14, a homeodomainleucine zipper I transcription factor, is strongly induced by drought stress in various cassava cultivars.However, the role of MeHDZ14 in cassava growth regulation has remained unclear. Here we report that MeHDZ14 affected plant height, such that a dwarf phenotype and altered internode elongation were observed in transgenic cassava lines. MeHDZ14 was found to negatively regulate the biosynthesis of lignin. Its overexpression resulted in abaxially rolled leaves. The morphogenesis of leaf epidermal cells was inhibited by overexpression of MeHDZ14, with decreased auxin and gibberellin and increased cytokinin contents. MeHDZ14 was found to regulate many drought-responsive genes, including genes involved in cell wall synthesis and expansion. MeHDZ14 bound to the promoter of caffeic acid 3-Omethyltransferase 1(MeCOMT1), acting as a transcriptional repressor of genes involved in cell wall development. MeHDZ14 appears to act as a negative regulator of internode elongation and epidermal cell morphogenesis during cassava leaf development.
文摘In this study, we analyze the binding of nuclear proteins isolated from the hydroxyurea (Hu)-induced and uninduced HEL cells to the DNasel hypersensitive sites Ⅲ (HS3 -14991 --14716 bp) and Ⅳ(HS4 -18586-18306 bp) in the human p-globin gene locus control region (LCR). Using Western blot assay, we demonstrate that GATA-1 transcription factor in HEL cells is increased following the induction of Hu, while GATA-2 transcription factor is decreased. Based on both the competition EMSA and the Western blot assay, our data reveal that the nuclear protein isolated from the uninduced HEL cells, which can bind to the HS3 and HS4 core DNA sequences, is mainly GATA-2; however, the nuclear proteins isolated from the Hu-induced HEL cells, which can bind to the HS3 and HS4 core DNA sequences, are mainly GATA-1 and GATA-X (a kind of unknown GATA factor). These results suggest that the erythroid specific transcription factors (GATA-1 and GATA-2) in the Hu-induced and uninduced HEL cells can selectively bind to the HS3
基金supported by the Modern Agricultural Industry Technology System of China (225020611)the National Natural Science Foundation of China (31501724)the China Postdoctoral Science Foundation (2015M580881)
文摘Homeobox 1 in Malusxdomestica （MdHB-1） is a transcription factor that belongs to homeodomain-leucine zipper I （HD-Zip I） protein subfamily. According to previous reports, MdHB-1 could regulate ethylene synthesis by binding with the MdAC01 promoter, but other functions of MdHB-1 are still unknown. To reveal more clues concerning the characters of the MdHB-1 gene promoter and the functions of MdHB-1, the promoter region of MdHB-1 was cloned from the Royal Gala apple genome and recombined with the 13-glucuronidase （GUS） gene in this study. This research was conducted in Nicotiana tabacum and supported by Agrobacterium-mediated transient transformation and bioinformatics analysis. Deletion analysis of the MdHB-1 promoter showed that the GUS gene could be activated by serially deleted promoters, and the activity promoted by 680 nucleotides （nt） was the lowest. The region, which is 266 nt upstream of the initiation code （ATG）, was effective for GUS expression. Meanwhile, the activity of the MdHB-1 promoter （-1 057 nt）, which was stronger than MdHB-1 promoter （-1 057 to -266 nt） and lack the 5＂-untranslated region （5＂-UTR）, showed that 5＂-UTR may have a positive effect on gene transcription. After the sequence analysis, the cis-acting elements that respond to hormones and environmental stresses were identified in the promoter region. The MdHB-1 promoter （1 057 nt） activity in Nicotiana tabacum was positively induced by ethrel and darkness, and it was suppressed by gibberellic acid （GA）, whereas abscisic acid （ABA）, salicylic acid （SA）, wounding, and Pseudomonas syringae pv. tomato （DC3000） treatments revealed a slight auxo-action. These results reveal that the MdHB-1 promoter receive internal or external signals, and MdHB-1 may refer to many biological activities in apple, such as its stress response, development, and ripening.
文摘The zinc finger motif was used as a vehicle for the initial discovery of Ikaros in the context of T-cell differentiation and has been central to all subsequent analyses of Ikaros function.The Ikaros gene is alternately spliced to produce several isoforms that confer diversity of function and consequently have complicated analysis of the function of Ikaros in vivo.Key features of Ikaros in vivo function are associated with six C2H2 zinc fingers;four of which are alternately incorporated in the production of the various Ikaros isoforms.Although no complete structures are available for the Ikaros protein or any of its family members,considerable evidence has accumulated about the structure of zinc fingers and the role that this structure plays in the functions of the Ikaros family of proteins.This review summarizes the structural aspects of Ikaros zinc fingers,individually,and in tandem to provide a structural context for Ikaros function and to provide a structural basis to inform the design of future experiments with Ikaros and its family members.
文摘Transcription factors play key roles in plant development and stress responses through their interaction with cis-elements and/or other transcription factors. Homeodomain associated leucine zipper proteins (HD-Zip) constitute a family of transcription factors that are characterized by the presence of a DNA-binding domain closely linked with leucine zipper motif functioning in dimer formation. This type of association is unique to plants and considered as an excellent candidate to activate developmental responses to altering environmental conditions. Cotton is the most important fiber plant with a lot of local and commercial uses in the world. HD-Zip proteins not only have key roles in different stages of vascular and inter-fascicular fiber differentiation of cotton but also are suggested to have an important role against abiotic stress that is one of the key factors limiting cotton productivity. Plants have developed various strategies to manage stress conditions through a combination of metabolic, physiological and morphological adaptations. These adaptive changes rely largely on alterations in gene expression. Therefore, transcriptional regulators play a crucial role in stress tolerance. Being a transcription factor HD-Zip might be a useful target for genetic engineering to generate multiple stress tolerance in susceptible plants. In the following chapter, we discussed how the HD-Zip proteins would play a useful role for cotton development both in fiber production and stress adaptation.
基金supported by the NSFC (31971671)the Fundamental Research Funds for the Central Universities of China (2572018CL04)+1 种基金the China Postdoctoral Science Foundation (2021M700733)the Heilongjiang Touyan Innovation Team Program (Tree Genetics and Breeding Innovation Team)。
文摘It is of great importance to better understand how trees regulate nitrogen(N) uptake under N deficiency conditions which severely challenge afforestation practices, yet the underlying molecular mechanisms have not been well elucidated. Here,we functionally characterized PuHox52, a Populus ussuriensis HD-ZIP transcription factor, whose overexpression greatly enhanced nutrient uptake and plant growth under N deficiency. We first conducted an RNA sequencing experiment to obtain root transcriptome using PuHox52-overexpression lines of P. ussuriensis under low N treatment. We then performed multiple genetic and phenotypic analyses to identify key target genes of PuHox52 and validated how they acted against N deficiency under PuHox52 regulation.PuHox52 was specifically induced in roots by N deficiency, and overexpression of PuHox52promoted N uptake, plant growth, and root development. We demonstrated that several nitrate-responsive genes(PuNRT1.1, PuNRT2.4,PuCLC-b, PuNIA2, PuNIR1, and PuNLP1),phosphate-responsive genes(PuPHL1A and PuPHL1B), and an iron transporter gene(PuIRT1) were substantiated to be direct targets of PuHox52. Among them, PuNRT1.1, PuPHL1A/B, and PuIRT1 were upregulated to relatively higher levels during PuHox52-mediated responses against N deficiency in PuHox52-overexpression lines compared to WT. Our study revealed a novel regulatory mechanism underlying root adaption to N deficiency where PuHox52 modulated a coordinated uptake of nitrate, phosphate, and iron through 'PuHox52-PuNRT1.1', 'PuHox52-PuPHL1A/PuPHL1B', and'PuHox52-PuIRT1' regulatory relationships in poplar roots.
