Linked Life Data

12941880

Source:http://linkedlifedata.com/resource/pubmed/id/12941880

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2003-8-27
pubmed:abstractText
The Arabidopsis thaliana AHK4 histidine kinase (also known as CRE1 or WOL) acts as a cytokinin signal transducer, presumably, in concert with downstream components, such as histidine-containing phosphotransfer factors (AHPs) and response regulators (ARRs), through the histidine-to-aspartate (His-->Asp) phosphorelay. Among 10 members of the type-A ARR family, the cytokinin-induced expression of ARR15 in roots is selectively impaired in the cre1-1 mutant, which carries a mutation in the AHK4 gene, suggesting a link between this type-A response regulator and the AHK4-mediated cytokinin signal transduction in roots. To address this issue further, we characterized a T-DNA insertion mutant of ARR15, and also constructed transgenic lines (referred to as ARR15-ox) that overexpress the ARR15 gene in a manner independent of cytokinin. While the T-DNA insertion mutant (arr15-1) showed no apparent phenotype, the cytokinin-independent overexpression of ARR15 in ARR15-ox plants resulted in a reduced sensitivity toward exogenously applied cytokinin, not only in elongation of roots in plants, but also in green callus formation (or shoot formation) in explants. Cytokinin-induced expressions of certain type-A ARRs were also down-regulated in ARR15-ox plants. These results support the view that ARR15 acts as a repressor that mediates a negative feedback loop in the cytokinin and AHK4-mediated His-->Asp phosphorelay.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0032-0781
pubmed:author
pubmed:issnType
Print
pubmed:volume
44
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
868-74
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
The type-A response regulator, ARR15, acts as a negative regulator in the cytokinin-mediated signal transduction in Arabidopsis thaliana.
pubmed:affiliation
Laboratory of Molecular Microbiology, School of Agriculture, Nagoya University, Chikusa-ku, Nagoya 464-8601, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't