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1.
Plant J ; 66(6): 1020-31, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21435046

RESUMO

The BASIC PENTACYSTEINE (BPC) proteins are a plant-specific transcription factor family that is present throughout land plants. The Arabidopsis BPC proteins have been categorized into three classes based on sequence similarity, and we demonstrate that there is functional overlap between classes. Single gene mutations produce no visible phenotypic effects, and severe morphological phenotypes occur only in higher order mutants between members of classes I and II, with the most severe phenotype observed in bpc1-1 bpc2 bpc4 bpc6 plants. These quadruple mutants are dwarfed and display small curled leaves, aberrant ovules, altered epidermal cells and reduced numbers of lateral roots. Affected processes include coordinated growth of cell layers, cell shape determination and timing of senescence. Disruption of BPC3 function rescues some aspects of the bpc1-1 bpc2 bpc4 bpc6 phenotype, indicating that BPC3 function may be antagonistic to other members of the family. Ethylene response is diminished in bpc1-1 bpc2 bpc4 bpc6 plants, although not all aspects of the phenotype can be explained by reduced ethylene sensitivity. Our data indicate that the BPC transcription factor family is integral for a wide range of processes that support normal growth and development.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Família Multigênica , Fatores de Transcrição/metabolismo , Alelos , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/ultraestrutura , Proteínas de Arabidopsis/genética , Clonagem Molecular , Etilenos/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Pleiotropia Genética , Hipocótilo/crescimento & desenvolvimento , Inflorescência/crescimento & desenvolvimento , Mutagênese Insercional , Óvulo Vegetal/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/ultraestrutura , Raízes de Plantas/crescimento & desenvolvimento , Mutação Puntual , Regiões Promotoras Genéticas , Pseudogenes , Fatores de Transcrição/genética
2.
Plant J ; 46(3): 522-31, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16623911

RESUMO

The Arabidopsis aberrant testa shape (ats) mutant produces a single integument instead of the two integuments seen in wild-type ovules. Cellular anatomy and patterns of marker gene expression indicate that the single integument results from congenital fusion of the two integuments of the wild type. Isolation of the ATS locus showed it to encode a member of the KANADI (KAN) family of putative transcription factors, previously referred to as KAN4. ATS was expressed at the border between the two integuments at the time of their initiation, with expression later confined to the abaxial layer of the inner integument. In an inner no outer (ino) mutant background, where an outer integument does not form, the ats mutation led to amorphous inner integument growth. The kan1kan2 double mutant exhibits a similar amorphous growth of the outer integument without affecting inner integument growth. We hypothesize that ATS and KAN1/KAN2 play similar roles in the specification of polarity in the inner and outer integuments, respectively, that parallel the known roles of KAN proteins in promoting abaxial identity during leaf development. INO and other members of the YABBY gene family have been hypothesized to have similar parallel roles in outer integument and leaf development. Together, these two hypotheses lead us to propose a model for normal integument growth that also explains the described mutant phenotypes.


Assuntos
Proteínas de Arabidopsis/fisiologia , Fatores de Transcrição/fisiologia , Sequência de Aminoácidos , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Polaridade Celular/fisiologia , Flores/crescimento & desenvolvimento , Flores/metabolismo , Flores/ultraestrutura , Dados de Sequência Molecular , Família Multigênica , Mutação , Sementes/citologia , Sementes/crescimento & desenvolvimento , Sementes/ultraestrutura , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
3.
Cancer Genet Cytogenet ; 161(1): 70-3, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16080960

RESUMO

Fluorescence in situ hybridization (FISH) analysis of the bone marrow of a 24-year-old man diagnosed with acute promyelocytic leukemia (APL) revealed a variant pattern with one fusion signal instead of the typical two fusions expected with the probe set used. The combined FISH and conventional chromosome analyses suggested that two subsequent translocations had occurred in this patient involving the same chromosomes 15 and 17. As the prognostic outcome in APL is strictly associated with the presence of a PML/RARA fusion, it is useful and necessary to perform both cytogenetic and FISH analyses of a variant t(15;17) to determine the status of the PML/RARA fusion.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 15/genética , Cromossomos Humanos Par 17/genética , Leucemia Promielocítica Aguda/genética , Proteínas de Neoplasias/genética , Proteínas de Fusão Oncogênica/genética , Translocação Genética/genética , Adulto , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Leucemia Promielocítica Aguda/patologia , Masculino , Proteínas de Neoplasias/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Células Tumorais Cultivadas
4.
Plant Physiol ; 137(2): 651-62, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15665244

RESUMO

Members of the YABBY family of putative transcription factors participate in abaxial-adaxial identity determination in lateral organs in Arabidopsis (Arabidopsis thaliana). Two YABBY genes specifically expressed in reproductive structures, CRABS CLAW (CRC) and INNER NO OUTER (INO), have additional activities, with CRC promoting nectary development and carpel fusion, and INO responding to spatial regulation by SUPERMAN during ovule development. All YABBY coding regions, except YABBY5, were able to restore outer integument growth in ino-1 mutants when expressed from the INO promoter (PRO(INO)). However, INO was the only YABBY family member that responded correctly to SUPERMAN to maintain the wild-type gynoapical-gynobasal asymmetry of the outer integument. By contrast, INO, FILAMENTOUS FLOWER, and YABBY3 failed to complement crc-1 when expressed from PRO(CRC). Roles of individual regions of CRC and INO in these effects were assessed using chimeric proteins with PRO(INO) and PRO(CRC) and the relatively constitutive cauliflower mosaic virus PRO(35S). Regions of CRC were found to contribute additively to CRC-specific functions in nectary and carpel formation, with a nearly direct relationship between the amount of CRC included and the degree of complementation of crc-1. When combined with INO sequences, the central and carboxyl-terminal regions of CRC were individually sufficient to overcome inhibitory effects of SUPERMAN within the outer integument. Reproductive phenotypes resulting from constitutive expression were dependent on the nature of the central region with some contributions from the amino terminus. Thus, the YABBY family members have both unique and common functional capacities, and residues involved in differential activities are distributed throughout the protein sequences.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/fisiologia , Família Multigênica/fisiologia , Fatores de Transcrição/fisiologia , Sequência de Aminoácidos , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Plantas Geneticamente Modificadas , Proteínas Recombinantes de Fusão , Reprodução , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Fatores de Transcrição/química , Fatores de Transcrição/genética
5.
Plant J ; 37(3): 426-38, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14731261

RESUMO

INNER NO OUTER (INO) expression is limited to the abaxial cell layer of the incipient and developing outer integument in Arabidopsis ovules. Using deletion analysis of the previously defined INO promoter (P-INO), at least three distinct regions that contribute to the endogenous INO expression pattern were identified. One such positive element, designated POS9, which comprises at least three distinct subelements, was found to include sufficient information to duplicate the INO expression pattern when four or more copies were used in conjunction with a heterologous minimal promoter. While known regulators of INO, including INO, SUPERMAN, BELL1, and AINTEGUMENTA, did not detectably interact with POS9 in yeast one-hybrid assays, two groups of proteins that interact specifically with POS9 were identified in one-hybrid library screens. Members of one group include C2H2 zinc finger motifs. Members of the second group contain a novel, conserved DNA-binding region and were designated the BASIC PENTACYSTEINE (BPC) proteins on the basis of conserved features of this region. The BPC proteins are nuclear localized and specifically bind in vitro to GA dinucleotide repeats located within POS9. The widespread expression patterns of the BPCs and the large number of GA repeat potential target sequences in the Arabidopsis genome indicate that BPC proteins may affect expression of genes involved in a variety of plant processes.


Assuntos
Arabidopsis/genética , Sequências Reguladoras de Ácido Nucleico , Sequência de Aminoácidos , Sequência de Bases , DNA de Plantas , Ensaio de Desvio de Mobilidade Eletroforética , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Homologia de Sequência de Aminoácidos
6.
Development ; 129(18): 4281-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12183380

RESUMO

The outer integument of Arabidopsis ovules exhibits marked polarity in its development, growing extensively from the abaxial side, but only to a very limited extent from the adaxial side of the ovule. Mutations in two genes affect this asymmetric growth. In strong inner no outer (ino) mutants outer integument growth is eliminated, whereas in superman (sup) mutants integument growth on the adaxial side is nearly equal to wild-type growth on the abaxial side. Through complementation and reporter gene analysis, a region of INO 5'-flanking sequences was identified that contains sufficient information for appropriate expression of INO. Using this INO promoter (P-INO) we show that INO acts as a positive regulator of transcription from P-INO, but is not sufficient for de novo initiation of transcription in other plant parts. Protein fusions demonstrate nuclear localization of INO, consistent with a proposed role as a transcription factor for this member of the YABBY protein family. Through its ability to inhibit expression of the endogenous INO gene and transgenes driven by P-INO, SUP is shown to be a negative regulator of INO transcription. Substitution of another YABBY protein coding region (CRABS CLAW) for INO overcomes this negative regulation, indicating that SUP suppresses INO transcription through attenuation of the INO positive autoregulatory loop.


Assuntos
Proteínas de Arabidopsis , Arabidopsis/fisiologia , Regulação da Expressão Gênica de Plantas , Mutação , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Sequência de Bases , Polaridade Celular , Genes Reporter , Glucuronidase/genética , Homeostase , Plantas Geneticamente Modificadas , Proteínas Recombinantes de Fusão/metabolismo , Mapeamento por Restrição , Sementes/fisiologia , Supressão Genética , Dedos de Zinco
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