Linked Life Data

20203237

Source:http://linkedlifedata.com/resource/pubmed/id/20203237

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2010-4-12
pubmed:abstractText
Plant phytochromes, molecular light switches that regulate various aspects of plant growth and development, are phosphoproteins that are also known to be autophosphorylating serine/threonine kinases. Although a few protein phosphatases that directly interact with and dephosphorylate phytochromes have been identified, no protein kinase that acts on phytochromes has been reported thus far, and the exact site of phytochrome autophosphorylation has not been identified. In this study, we investigated the functional role of phytochrome autophosphorylation. We first mapped precisely the autophosphorylation sites of oat phytochrome A (phyA), and identified Ser8 and Ser18 in the 65 amino acid N-terminal extension (NTE) region as being the autophosphorylation sites. The in vivo functional roles of phytochrome autophosphorylation were examined by introducing autophosphorylation site mutants into phyA-deficient Arabidopsis thaliana. We found that all the transgenic plants expressing the autophosphorylation site mutants exhibited hypersensitive light responses, indicating an increase in phyA activity. Further analysis showed that these phyA mutant proteins were degraded at a significantly slower rate than wild-type phyA under light conditions, which suggests that the increased phyA activity of the mutants is related to their increased protein stability. In addition, protoplast transfection analyses with green fluorescent protein (GFP)-fused phyA constructs showed that the autophosphorylation site mutants formed sequestered areas of phytochrome (SAPs) in the cytosol much more slowly than did wild-type phyA. These results suggest that the autophosphorylation of phyA plays an important role in the regulation of plant phytochrome signaling through the control of phyA protein stability.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
1471-9053
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
51
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
596-609
pubmed:dateRevised
2011-3-1
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Functional characterization of phytochrome autophosphorylation in plant light signaling.
pubmed:affiliation
Department of Biotechnology and Kumho Life Science Laboratory, Chonnam National University, Gwangju 500-757, Korea.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't