Linked Life Data

14731256

Source:http://linkedlifedata.com/resource/pubmed/id/14731256

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2004-1-20
pubmed:abstractText
HAB1 was originally cloned on the basis of sequence homology to ABI1 and ABI2, and indeed, a multiple sequence alignment of 32 Arabidopsis protein phosphatases type-2C (PP2Cs) reveals a cluster composed by the four closely related proteins, ABI1, ABI2, HAB1 and At1g17550 (here named HAB2). Characterisation of transgenic plants harbouring a transcriptional fusion ProHAB1: green fluorescent protein (GFP) indicates that HAB1 is broadly expressed within the plant, including key target sites of abscisic acid (ABA) action as guard cells or seeds. The expression of the HAB1 mRNA in vegetative tissues is strongly upregulated in response to exogenous ABA. In this work, we show that constitutive expression of HAB1 in Arabidopsis under a cauliflower mosaic virus (CaMV) 35S promoter led to reduced ABA sensitivity both in seeds and vegetative tissues, compared to wild-type plants. Thus, in the field of ABA signalling, this work represents an example of a stable phenotype in planta after sustained overexpression of a PP2C genes. Additionally, a recessive T-DNA insertion mutant of HAB1 was analysed in this work, whereas previous studies of recessive alleles of PP2C genes were carried out with intragenic revertants of the abi1-1 and abi2-1 mutants that carry missense mutations in conserved regions of the PP2C domain. In the presence of exogenous ABA, hab1-1 mutant shows ABA-hypersensitive inhibition of seed germination; however, its transpiration rate was similar to that of wild-type plants. The ABA-hypersensitive phenotype of hab1-1 seeds together with the reduced ABA sensitivity of 35S:HAB1 plants are consistent with a role of HAB1 as a negative regulator of ABA signalling. Finally, these results provide new genetic evidence on the function of a PP2C in ABA signalling.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0960-7412
pubmed:author
pubmed:issnType
Print
pubmed:volume
37
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
354-69
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Gain-of-function and loss-of-function phenotypes of the protein phosphatase 2C HAB1 reveal its role as a negative regulator of abscisic acid signalling.
pubmed:affiliation
Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas, Camino de Vera, E-46022 Valencia, Spain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't