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1.
Plant Cell ; 35(9): 3504-3521, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37440281

RESUMO

ADAPTOR-ASSOCIATED PROTEIN KINASE1 (AAK1) is a known regulator of clathrin-mediated endocytosis in mammals. Human AAK1 phosphorylates the µ2 subunit of the ADAPTOR PROTEIN-2 (AP-2) complex (AP2M) and plays important roles in cell differentiation and development. Previous interactome studies discovered the association of AAK1 with AP-2 in Arabidopsis (Arabidopsis thaliana), but its function was unclear. Here, genetic analysis revealed that the Arabidopsis aak1 and ap2m mutants both displayed altered root tropic growth, including impaired touch- and gravity-sensing responses. In Arabidopsis, AAK1-phosphorylated AP2M on Thr-163, and expression of the phospho-null version of AP2M in the ap2m mutant led to an aak1-like phenotype, whereas the phospho-mimic forms of AP2M rescued the aak1 mutant. In addition, we found that the AAK1-dependent phosphorylation state of AP2M modulates the frequency distribution of endocytosis. Our data indicate that the phosphorylation of AP2M on Thr-163 by AAK1 fine-tunes endocytosis in the Arabidopsis root to control its tropic growth.


Assuntos
Subunidades mu do Complexo de Proteínas Adaptadoras , Arabidopsis , Raízes de Plantas , Animais , Humanos , Complexo 2 de Proteínas Adaptadoras/genética , Complexo 2 de Proteínas Adaptadoras/metabolismo , Subunidades mu do Complexo de Proteínas Adaptadoras/metabolismo , Arabidopsis/metabolismo , Clatrina/metabolismo , Endocitose/genética , Mamíferos/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
2.
Plant Physiol ; 195(3): 1807-1817, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38513700

RESUMO

Signal transduction relies largely on the activity of kinases and phosphatases that control protein phosphorylation. However, we still know very little about phosphorylation-mediated signaling networks. Plant MITOGEN-ACTIVATED PROTEIN KINASE KINASE KINASE KINASEs (MAP4Ks) have recently gained more attention, given their role in a wide range of processes, including developmental processes and stress signaling. We analyzed MAP4K expression patterns and mapped protein-MAP4K interactions in Arabidopsis (Arabidopsis thaliana), revealing extensive coexpression and heterodimerization. This heterodimerization is regulated by the C-terminal, intrinsically disordered half of the MAP4K, and specifically by the coiled coil motif. The ability to heterodimerize is required for proper activity and localization of the MAP4Ks. Taken together, our results identify MAP4K-interacting proteins and emphasize the functional importance of MAP4K heterodimerization. Furthermore, we identified MAP4K4/TARGET OF TEMPERATURE3 (TOT3) and MAP4K5/TOT3-INTERACTING PROTEIN 5 (TOI5) as key regulators of the transition from cell division to elongation zones in the primary root tip.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Multimerização Proteica , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/enzimologia , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Domínios Proteicos , Fosforilação , Plantas Geneticamente Modificadas
3.
EMBO Rep ; 24(9): e54709, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37458257

RESUMO

Endocytosis regulates the turnover of cell surface localized receptors, which are crucial for plants to rapidly respond to stimuli. The evolutionary ancient TPLATE complex (TPC) plays an essential role in endocytosis in Arabidopsis plants. Knockout or knockdown of single TPC subunits causes male sterility and seedling lethality phenotypes, complicating analysis of the roles of TPC during plant development. Partially functional alleles of TPC subunits however only cause mild developmental deviations. Here, we took advantage of the partially functional TPLATE allele, WDXM2, to investigate a role for TPC-dependent endocytosis in receptor-mediated signaling. We discovered that reduced TPC-dependent endocytosis confers a hypersensitivity to very low doses of CLAVATA3 peptide signaling. This hypersensitivity correlated with the abundance of the CLAVATA3 receptor protein kinase CLAVATA1 at the plasma membrane. Genetic and biochemical analysis as well as live-cell imaging revealed that TPC-dependent regulation of CLAVATA3-dependent internalization of CLAVATA1 from the plasma membrane is required for shoot stem cell homeostasis. Our findings provide evidence that TPC-mediated endocytosis and degradation of CLAVATA1 is a mechanism to dampen CLAVATA3-mediated signaling during plant development.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Endocitose , Regulação da Expressão Gênica de Plantas , Meristema/genética , Plantas/metabolismo , Receptores de Superfície Celular/metabolismo , Transdução de Sinais
4.
Proc Natl Acad Sci U S A ; 119(11): e2118220119, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35254915

RESUMO

SignificanceChemical genetics, which investigates biological processes using small molecules, is gaining interest in plant research. However, a major challenge is to uncover the mode of action of the small molecules. Here, we applied the cellular thermal shift assay coupled with mass spectrometry (CETSA MS) to intact Arabidopsis cells and showed that bikinin, the plant-specific glycogen synthase kinase 3 (GSK3) inhibitor, changed the thermal stability of some of its direct targets and putative GSK3-interacting proteins. In combination with phosphoproteomics, we also revealed that GSK3s phosphorylated the auxin carrier PIN-FORMED1 and regulated its polarity that is required for the vascular patterning in the leaf.


Assuntos
Brassinosteroides/metabolismo , Ácidos Indolacéticos/metabolismo , Proteoma , Transdução de Sinais , Aminopiridinas/metabolismo , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Fosfoproteínas/metabolismo , Ligação Proteica , Estabilidade Proteica , Proteômica/métodos , Succinatos/metabolismo
5.
Genes Dev ; 31(6): 617-627, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28404632

RESUMO

In many plants, the asymmetric division of the zygote sets up the apical-basal axis of the embryo. Unlike animals, plant zygotes are transcriptionally active, implying that plants have evolved specific mechanisms to control transcriptional activation of patterning genes in the zygote. In Arabidopsis, two pathways have been found to regulate zygote asymmetry: YODA (YDA) mitogen-activated protein kinase (MAPK) signaling, which is potentiated by sperm-delivered mRNA of the SHORT SUSPENSOR (SSP) membrane protein, and up-regulation of the patterning gene WOX8 by the WRKY2 transcription factor. How SSP/YDA signaling is transduced into the nucleus and how these pathways are integrated have remained elusive. Here we show that paternal SSP/YDA signaling directly phosphorylates WRKY2, which in turn leads to the up-regulation of WOX8 transcription in the zygote. We further discovered the transcription factors HOMEODOMAIN GLABROUS11/12 (HDG11/12) as maternal regulators of zygote asymmetry that also directly regulate WOX8 transcription. Our results reveal a framework of how maternal and paternal factors are integrated in the zygote to regulate embryo patterning.


Assuntos
Arabidopsis/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Transcrição Gênica , Zigoto/metabolismo , Arabidopsis/enzimologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/biossíntese , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Sistema de Sinalização das MAP Quinases , Herança Materna , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Herança Paterna , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Zigoto/enzimologia
6.
EMBO J ; 39(1): e101515, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31617603

RESUMO

The phytohormone auxin controls plant growth and development via TIR1-dependent protein degradation of canonical AUX/IAA proteins, which normally repress the activity of auxin response transcription factors (ARFs). IAA33 is a non-canonical AUX/IAA protein lacking a TIR1-binding domain, and its role in auxin signaling and plant development is not well understood. Here, we show that IAA33 maintains root distal stem cell identity and negatively regulates auxin signaling by interacting with ARF10 and ARF16. IAA33 competes with the canonical AUX/IAA repressor IAA5 for binding to ARF10/16 to protect them from IAA5-mediated inhibition. In contrast to auxin-dependent degradation of canonical AUX/IAA proteins, auxin stabilizes IAA33 protein via MITOGEN-ACTIVATED PROTEIN KINASE 14 (MPK14) and does not affect IAA33 gene expression. Taken together, this study provides insight into the molecular functions of non-canonical AUX/IAA proteins in auxin signaling transduction.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ácidos Indolacéticos/farmacologia , Proteínas Nucleares/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA/genética , Proteínas Nucleares/genética , Fosforilação , Reguladores de Crescimento de Plantas/farmacologia , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Proteólise , Transdução de Sinais
7.
New Phytol ; 241(2): 687-702, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37950543

RESUMO

Hypocotyl elongation is controlled by several signals and is a major characteristic of plants growing in darkness or under warm temperature. While already several molecular mechanisms associated with this process are known, protein degradation and associated E3 ligases have hardly been studied in the context of warm temperature. In a time-course phosphoproteome analysis on Arabidopsis seedlings exposed to control or warm ambient temperature, we observed reduced levels of diverse proteins over time, which could be due to transcription, translation, and/or degradation. In addition, we observed differential phosphorylation of the LRR F-box protein SLOMO MOTION (SLOMO) at two serine residues. We demonstrate that SLOMO is a negative regulator of hypocotyl growth, also under warm temperature conditions, and protein-protein interaction studies revealed possible interactors of SLOMO, such as MKK5, DWF1, and NCED4. We identified DWF1 as a likely SLOMO substrate and a regulator of warm temperature-mediated hypocotyl growth. We propose that warm temperature-mediated regulation of SLOMO activity controls the abundance of hypocotyl growth regulators, such as DWF1, through ubiquitin-mediated degradation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas F-Box , Arabidopsis/metabolismo , Hipocótilo/metabolismo , Proteínas de Arabidopsis/metabolismo , Temperatura , Proteínas F-Box/metabolismo , Regulação da Expressão Gênica de Plantas
8.
Plant Physiol ; 192(1): 256-273, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36747317

RESUMO

Throughout the exploration of the soil, roots interact with their environment and adapt to different conditions. Directional root growth is guided by asymmetric molecular patterns but how these become established or are dynamically regulated is poorly understood. Asymmetric gradients of the phytohormone auxin are established during root gravitropism, mainly through directional transport mediated by polarized auxin transporters. Upon gravistimulation, PIN-FORMED2 (PIN2) is differentially distributed and accumulates at the lower root side to facilitate asymmetric auxin transport up to the elongation zone where it inhibits cell elongation. GOLVEN (GLV) peptides function in gravitropism by affecting PIN2 abundance in epidermal cells. In addition, GLV signaling through ROOT GROWTH FACTOR 1 INSENSITIVE (RGI) receptors regulates root apical meristem maintenance. Here, we show that GLV-RGI signaling in these 2 processes in Arabidopsis (Arabidopsis thaliana) can be mapped to different cells in the root tip and that, in the case of gravitropism, it operates mainly in the lateral root cap (LRC) to maintain PIN2 levels at the plasma membrane (PM). Furthermore, we found that GLV signaling upregulates the phosphorylation level of PIN2 in an RGI-dependent manner. In addition, we demonstrated that the RGI5 receptor is asymmetrically distributed in the LRC and accumulates in the lower side of the LRC after gravistimulation. Asymmetric GLV-RGI signaling in the root cap likely accounts for differential PIN2 abundance at the PM to temporarily support auxin transport up to the elongation zone, thereby representing an additional level of control on the asymmetrical auxin flux to mediate differential growth of the root.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Gravitropismo/fisiologia , Proteínas de Arabidopsis/metabolismo , Raízes de Plantas/metabolismo , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo
9.
J Exp Bot ; 75(15): 4611-4624, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38872385

RESUMO

Post-translational modifications (PTMs) greatly increase protein diversity and functionality. To help the plant research community interpret the ever-increasing number of reported PTMs, the Plant PTM Viewer (https://www.psb.ugent.be/PlantPTMViewer) provides an intuitive overview of plant protein PTMs and the tools to assess it. This update includes 62 novel PTM profiling studies, adding a total of 112 000 modified peptides reporting plant PTMs, including 14 additional PTM types and three species (moss, tomato, and soybean). Furthermore, an open modification re-analysis of a large-scale Arabidopsis thaliana mass spectrometry tissue atlas identified previously uncharted landscapes of lysine acylations predominant in seed and flower tissues and 3-phosphoglycerylation on glycolytic enzymes in plants. An extra 'Protein list analysis' tool was developed for retrieval and assessing the enrichment of PTMs in a protein list of interest. We conducted a protein list analysis on nuclear proteins, revealing a substantial number of redox modifications in the nucleus, confirming previous assumptions regarding the redox regulation of transcription. We encourage the plant research community to use PTM Viewer 2.0 for hypothesis testing and new target discovery, and also to submit new data to expand the coverage of conditions, plant species, and PTM types, thereby enriching our understanding of plant biology.


Assuntos
Proteínas de Plantas , Processamento de Proteína Pós-Traducional , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Plantas/metabolismo
10.
Plant Cell Physiol ; 63(12): 1968-1979, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34679169

RESUMO

The rice root system is primarily composed of shoot-borne adventitious/crown roots (ARs/CRs) that develop from the coleoptile base, and therefore, it is an excellent model system for studying shoot-to-root trans-differentiation process. We reveal global changes in protein and metabolite abundance and protein phosphorylation in response to an auxin stimulus during CR development. The liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) analyses of developing crown root primordia (CRP) and emerged CRs identified 334 proteins and 12 amino acids, respectively, that were differentially regulated upon auxin treatment. Gene ontology enrichment analysis of global proteome data uncovered the biological processes associated with chromatin conformational change, gene expression and cell cycle that were regulated by auxin signaling. Spatial gene expression pattern analysis of differentially abundant proteins disclosed their stage-specific dynamic expression pattern during CRP development. Further, our tempo-spatial gene expression and functional analyses revealed that auxin creates a regulatory module during CRP development and activates ethylene biosynthesis exclusively during CRP initiation. Further, the phosphoproteome analysis identified 8,220 phosphosites, which could be mapped to 1,594 phosphoproteins and of which 66 phosphosites were differentially phosphorylated upon auxin treatment. Importantly, we observed differential phosphorylation of the cyclin-dependent kinase G-2 (OsCDKG;2) and cell wall proteins, in response to auxin signaling, suggesting that auxin-dependent phosphorylation may be required for cell cycle activation and cell wall synthesis during root organogenesis. Thus, our study provides evidence for the translational and post-translational regulation during CR development downstream of the auxin signaling pathway.


Assuntos
Fenômenos Biológicos , Oryza , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/metabolismo , Oryza/metabolismo , Proteoma/metabolismo , Cromatografia Líquida , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Espectrometria de Massas em Tandem , Transdução de Sinais/genética , Regulação da Expressão Gênica de Plantas
11.
New Phytol ; 238(1): 270-282, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36597715

RESUMO

Guard cells control the opening of stomatal pores in the leaf surface, with the use of a network of protein kinases and phosphatases. Loss of function of the CBL-interacting protein kinase 23 (CIPK23) was previously shown to decrease the stomatal conductance, but the molecular mechanisms underlying this response still need to be clarified. CIPK23 was specifically expressed in Arabidopsis guard cells, using an estrogen-inducible system. Stomatal movements were linked to changes in ion channel activity, determined with double-barreled intracellular electrodes in guard cells and with the two-electrode voltage clamp technique in Xenopus oocytes. Expression of the phosphomimetic variant CIPK23T190D enhanced stomatal opening, while the natural CIPK23 and a kinase-inactive CIPK23K60N variant did not affect stomatal movements. Overexpression of CIPK23T190D repressed the activity of S-type anion channels, while their steady-state activity was unchanged by CIPK23 and CIPK23K60N . We suggest that CIPK23 enhances the stomatal conductance at favorable growth conditions, via the regulation of several ion transport proteins in guard cells. The inhibition of SLAC1-type anion channels is an important facet of this response.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico/metabolismo , Ânions/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Membrana/metabolismo , Estômatos de Plantas/fisiologia , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo
12.
Plant Cell ; 32(9): 2979-2996, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32690720

RESUMO

The anaphase promoting complex/cyclosome (APC/C) controls unidirectional progression through the cell cycle by marking key cell cycle proteins for proteasomal turnover. Its activity is temporally regulated by the docking of different activating subunits, known in plants as CELL DIVISION PROTEIN20 (CDC20) and CELL CYCLE SWITCH52 (CCS52). Despite the importance of the APC/C during cell proliferation, the number of identified targets in the plant cell cycle is limited. Here, we used the growth and meristem phenotypes of Arabidopsis (Arabidopsis thaliana) CCS52A2-deficient plants in a suppressor mutagenesis screen to identify APC/CCCS52A2 substrates or regulators, resulting in the identification of a mutant cyclin CYCA3;4 allele. CYCA3;4 deficiency partially rescues the ccs52a2-1 phenotypes, whereas increased CYCA3;4 levels enhance the scored ccs52a2-1 phenotypes. Furthermore, whereas the CYCA3;4 protein is promptly broken down after prophase in wild-type plants, it remains present in later stages of mitosis in ccs52a2-1 mutant plants, marking it as a putative APC/CCCS52A2 substrate. Strikingly, increased CYCA3;4 levels result in aberrant root meristem and stomatal divisions, mimicking phenotypes of plants with reduced RETINOBLASTOMA-RELATED PROTEIN1 (RBR1) activity. Correspondingly, RBR1 hyperphosphorylation was observed in CYCA3;4 gain-of-function plants. Our data thus demonstrate that an inability to timely destroy CYCA3;4 contributes to disorganized formative divisions, possibly in part caused by the inactivation of RBR1.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/citologia , Proteínas de Ciclo Celular/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Ciclo Celular/genética , Diferenciação Celular/genética , Divisão Celular , Metanossulfonato de Etila/farmacologia , Regulação da Expressão Gênica de Plantas , Meristema/citologia , Meristema/genética , Mutação , Fosforilação , Células Vegetais/efeitos dos fármacos , Folhas de Planta/citologia , Folhas de Planta/genética , Raízes de Plantas/citologia , Raízes de Plantas/genética , Caules de Planta/citologia , Plantas Geneticamente Modificadas , Polimorfismo de Nucleotídeo Único
13.
Nat Rev Mol Cell Biol ; 12(3): 177-88, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21346731

RESUMO

Asymmetric cell division generates two cells with different fates and has an important role in plant development. It produces distinct cell types and new organs, and maintains stem cell niches. To handle the constraints of having immobile cells, plants possess numerous unique features to obtain asymmetry, such as specific regulators of intrinsic polarity. Although several components have not yet been identified, new findings, together with knowledge from different developmental systems, now allow us to take an important step towards a mechanistic overview of asymmetric cell division in plants and algae. Strikingly, several key regulators are used for different developmental processes, and common mechanisms can be recognized.


Assuntos
Células Vegetais , Estramenópilas/citologia , Arabidopsis/citologia , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Ciclo Celular , Diferenciação Celular , Divisão Celular , Polaridade Celular , Fucus/citologia , Modelos Biológicos , Desenvolvimento Vegetal , Plantas/genética
14.
Mol Cell Proteomics ; 20: 100040, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33372050

RESUMO

The F-box protein MORE AXILLARY GROWTH 2 (MAX2) is a central component in the signaling cascade of strigolactones (SLs) as well as of the smoke-derived karrikins (KARs) and the so far unknown endogenous KAI2 ligand (KL). The two groups of molecules are involved in overlapping and unique developmental processes, and signal-specific outcomes are attributed to perception by the paralogous α/ß-hydrolases DWARF14 (D14) for SL and KARRIKIN INSENSITIVE 2/HYPOSENSITIVE TO LIGHT (KAI2/HTL) for KAR/KL. In addition, depending on which receptor is activated, specific members of the SUPPRESSOR OF MAX2 1 (SMAX1)-LIKE (SMXL) family control KAR/KL and SL responses. As proteins that function in the same signal transduction pathway often occur in large protein complexes, we aimed at discovering new players of the MAX2, D14, and KAI2 protein network by tandem affinity purification in Arabidopsis cell cultures. When using MAX2 as a bait, various proteins were copurified, among which were general components of the Skp1-Cullin-F-box complex and members of the CONSTITUTIVE PHOTOMORPHOGENIC 9 signalosome. Here, we report the identification of a novel interactor of MAX2, a type 5 serine/threonine protein phosphatase, designated PHYTOCHROME-ASSOCIATED PROTEIN PHOSPHATASE 5 (PAPP5). Quantitative affinity purification pointed at PAPP5 as being more present in KAI2 rather than in D14 protein complexes. In agreement, mutant analysis suggests that PAPP5 modulates KAR/KL-dependent seed germination under suboptimal conditions and seedling development. In addition, a phosphopeptide enrichment experiment revealed that PAPP5 might dephosphorylate MAX2 in vivo independently of the synthetic SL analog, rac-GR24. Together, by analyzing the protein complexes to which MAX2, D14, and KAI2 belong, we revealed a new MAX2 interactor, PAPP5, that might act through dephosphorylation of MAX2 to control mainly KAR/KL-related phenotypes and, hence, provide another link with the light pathway.


Assuntos
Proteínas de Arabidopsis/metabolismo , Proteínas de Transporte/metabolismo , Proteínas Nucleares/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Transporte/química , Proteínas de Transporte/genética , Germinação , Proteínas Nucleares/genética , Fosfoproteínas Fosfatases/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Nicotiana/genética
15.
J Integr Plant Biol ; 65(12): 2587-2603, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37846823

RESUMO

Interploidy hybridization between hexaploid and tetraploid genotypes occurred repeatedly during genomic introgression events throughout wheat evolution, and is commonly employed in wheat breeding programs. Hexaploid wheat usually serves as maternal parent because the reciprocal cross generates progeny with severe defects and poor seed germination, but the underlying mechanism is poorly understood. Here, we performed detailed analysis of phenotypic variation in endosperm between two interploidy reciprocal crosses arising from tetraploid (Triticum durum, AABB) and hexaploid wheat (Triticum aestivum, AABBDD). In the paternal- versus the maternal-excess cross, the timing of endosperm cellularization was delayed and starch granule accumulation in the endosperm was repressed, causing reduced germination percentage. The expression profiles of genes involved in nutrient metabolism differed strongly between these endosperm types. Furthermore, expression patterns of parental alleles were dramatically disturbed in interploidy versus intraploidy crosses, leading to increased number of imprinted genes. The endosperm-specific TaLFL2 showed a paternally imprinted expression pattern in interploidy crosses partially due to allele-specific DNA methylation. Paternal TaLFL2 binds to and represses a nutrient accumulation regulator TaNAC019, leading to reduced storage protein and starch accumulation during endosperm development in paternal-excess cross, as confirmed by interploidy crosses between tetraploid wild-type and clustered regularly interspaced palindromic repeats (CRISPR) - CRISPR-associated protein 9 generated hexaploid mutants. These findings reveal a contribution of genomic imprinting to paternal-excess interploidy hybridization barriers during wheat evolution history and explains why experienced breeders preferentially exploit maternal-excess interploidy crosses in wheat breeding programs.


Assuntos
Fatores de Transcrição , Triticum , Fatores de Transcrição/metabolismo , Triticum/genética , Sementes/genética , Tetraploidia , Melhoramento Vegetal , Isolamento Reprodutivo , Cruzamentos Genéticos , Endosperma/genética , Amido/metabolismo
16.
Plant J ; 108(1): 55-66, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34273207

RESUMO

Aluminium (Al) stress is a major limiting factor for worldwide crop production in acid soils. In Arabidopsis thaliana, the TAA1-dependent local auxin biosynthesis in the root-apex transition zone (TZ), the major perception site for Al toxicity, is crucial for the Al-induced root-growth inhibition, while the mechanism underlying Al-regulated auxin accumulation in the TZ is not fully understood. In the present study, the role of auxin transport in Al-induced local auxin accumulation in the TZ and root-growth inhibition was investigated. Our results showed that PIN-FORMED (PIN) proteins such as PIN1, PIN3, PIN4 and PIN7 and AUX1/LAX proteins such as AUX1, LAX1 and LAX2 were all ectopically up-regulated in the root-apex TZ in response to Al stress and coordinately regulated local auxin accumulation in the TZ and root-growth inhibition. The ectopic up-regulation of PIN1 in the TZ under Al stress was regulated by both ethylene and auxin, with auxin signalling acting downstream of ethylene. Al-induced PIN1 up-regulation and auxin accumulation in the root-apex TZ was also regulated by the calossin-like protein BIG. Together, our results provide insight into how Al stress induces local auxin accumulation in the TZ and root-growth inhibition through the local regulation of auxin transport.


Assuntos
Alumínio/toxicidade , Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Etilenos/metabolismo , Ácidos Indolacéticos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Transporte Biológico , Proteínas de Ligação a Calmodulina/genética , Proteínas de Ligação a Calmodulina/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Membrana Transportadoras/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Estresse Fisiológico , Regulação para Cima
17.
New Phytol ; 233(4): 1719-1731, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34787921

RESUMO

Heat stress is a major limiting factor for global wheat production and causes dramatic yield loss worldwide. The TaMBF1c gene is upregulated in response to heat stress in wheat. Understanding the molecular mechanisms associated with heat stress responses will pave the way to improve wheat thermotolerance. Through CRISPR/Cas9-based gene editing, polysome profiling coupled with RNA-sequencing analysis, and protein-protein interactions, we show that TaMBF1c conferred heat response via regulating a specific gene translation in wheat. The results showed that TaMBF1c is evolutionarily conserved in diploid, tetraploid and hexaploid wheat species, and its knockdown and knockout lines show increased heat sensitivity. TaMBF1c is colocalized with the stress granule complex and interacts with TaG3BP. TaMBF1c affects the translation efficiency of a subset of heat responsive genes, which are significantly enriched in the 'sequence-specific DNA binding' term. Moreover, gene expression network analysis demonstrated that TaMBF1c is closely associated with the translation of heat shock proteins. Our findings reveal a contribution of TaMBF1c in regulating the heat stress response via the translation process, and provide a new target for improving heat tolerance in wheat breeding programs.


Assuntos
Termotolerância , Triticum , Regulação da Expressão Gênica de Plantas , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Biossíntese de Proteínas , Grânulos de Estresse , Termotolerância/genética , Triticum/metabolismo
18.
J Exp Bot ; 73(8): 2308-2319, 2022 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-35085386

RESUMO

Much of what we know about the role of auxin in plant development derives from exogenous manipulations of auxin distribution and signaling, using inhibitors, auxins, and auxin analogs. In this context, synthetic auxin analogs, such as 1-naphthalene acetic acid (1-NAA), are often favored over the endogenous auxin, indole-3-acetic acid (IAA), in part due to their higher stability. While such auxin analogs have proven instrumental in revealing the various faces of auxin, they display in some cases bioactivities distinct from IAA. Here, we focused on the effect of auxin analogs on the accumulation of PIN proteins in brefeldin A-sensitive endosomal aggregations (BFA bodies), and correlation with the ability to elicit Ca2+ responses. For a set of commonly used auxin analogs, we evaluated if auxin analog-induced Ca2+ signaling inhibits PIN accumulation. Not all auxin analogs elicited a Ca2+ response, and their differential ability to elicit Ca2+ responses correlated partially with their ability to inhibit BFA-body formation. However, in tir1/afb and cngc14, 1-NAA-induced Ca2+ signaling was strongly impaired, yet 1-NAA still could inhibit PIN accumulation in BFA bodies. This demonstrates that TIR1/AFB-CNGC14-dependent Ca2+ signaling does not inhibit BFA body formation in Arabidopsis roots.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Cálcio/metabolismo , Ácidos Indolacéticos/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/metabolismo
19.
Mol Cell Proteomics ; 19(8): 1248-1262, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32404488

RESUMO

Peptides derived from non-functional precursors play important roles in various developmental processes, but also in (a)biotic stress signaling. Our (phospho)proteome-wide analyses of C-TERMINALLY ENCODED PEPTIDE 5 (CEP5)-mediated changes revealed an impact on abiotic stress-related processes. Drought has a dramatic impact on plant growth, development and reproduction, and the plant hormone auxin plays a role in drought responses. Our genetic, physiological, biochemical, and pharmacological results demonstrated that CEP5-mediated signaling is relevant for osmotic and drought stress tolerance in Arabidopsis, and that CEP5 specifically counteracts auxin effects. Specifically, we found that CEP5 signaling stabilizes AUX/IAA transcriptional repressors, suggesting the existence of a novel peptide-dependent control mechanism that tunes auxin signaling. These observations align with the recently described role of AUX/IAAs in stress tolerance and provide a novel role for CEP5 in osmotic and drought stress tolerance.


Assuntos
Adaptação Fisiológica , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Ácidos Indolacéticos/metabolismo , Peptídeos/metabolismo , Proteômica , Estresse Fisiológico , Adaptação Fisiológica/genética , Arabidopsis/genética , Transporte Biológico/genética , Secas , Regulação da Expressão Gênica de Plantas , Osmose , Fosfoproteínas/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteoma/metabolismo , Plântula/crescimento & desenvolvimento , Estresse Fisiológico/genética , Transcrição Gênica
20.
Proc Natl Acad Sci U S A ; 116(17): 8597-8602, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-30944225

RESUMO

In plants, postembryonic formation of new organs helps shape the adult organism. This requires the tight regulation of when and where a new organ is formed and a coordination of the underlying cell divisions. To build a root system, new lateral roots are continuously developing, and this process requires the tight coordination of asymmetric cell division in adjacent pericycle cells. We identified EXPANSIN A1 (EXPA1) as a cell wall modifying enzyme controlling the divisions marking lateral root initiation. Loss of EXPA1 leads to defects in the first asymmetric pericycle cell divisions and the radial swelling of the pericycle during auxin-driven lateral root formation. We conclude that a localized radial expansion of adjacent pericycle cells is required to position the asymmetric cell divisions and generate a core of small daughter cells, which is a prerequisite for lateral root organogenesis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Divisão Celular , Raízes de Plantas , Arabidopsis/citologia , Arabidopsis/enzimologia , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiologia , Divisão Celular/genética , Divisão Celular/fisiologia , Parede Celular/genética , Parede Celular/fisiologia , Raízes de Plantas/citologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/fisiologia , Transcriptoma
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