Linked Life Data

16709197

Source:http://linkedlifedata.com/resource/pubmed/id/16709197

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2006-5-19
pubmed:abstractText
The red and far-red light-absorbing phytochromes interact with the circadian clock, a central oscillator that sustains a 24-h period, to measure accurately seasonal changes in day-length and regulate the expression of several key flowering genes. The interactions and subsequent signalling steps upstream of the flowering genes such as CONSTANS (CO) and FLOWERING LOCUS T (FT) remain largely unknown. We report here that a photomorphogenic mutant, red and far-red insensitive 2-1 ( rfi2-1), flowered early particularly under long days. The rfi2-1 mutation also enhanced the expression of CO and FT under day/night cycles or constant light. Both co-2 and gigantea-2 (gi-2) were epistatic to rfi2-1 in their flowering responses. The gi-2 mutation was also epistatic to the rfi2-1 mutation in the expression of CO and hypocotyl elongation. However, the rfi2-1 mutation did not affect the expression of GI, a gene that mediates between the circadian clock and the expression of CO. Like many other flowering genes, the expression of RFI2 oscillated under day/night cycles and was rhythmic under constant light. The amplitude of the rhythmic expression of RFI2 was significantly reduced in phyB-9 or lhy-20 plants, and was also affected by the gi-2 mutation. As previously reported, the gi-2 mutation affects the period length and amplitude of CCA1 and LHY expression, and GI may act through a feedback loop to maintain a proper circadian function. We propose a regulatory step in which RFI2 represses the expression of CO, whereas GI may maintain the proper expression of RFI2 through its positive action on the circadian clock. The regulatory step serves to tune the circadian outputs that control the expression of CO and photoperiodic flowering.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0960-7412
pubmed:author
pubmed:issnType
Print
pubmed:volume
46
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
823-33
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
RFI2, a RING-domain zinc finger protein, negatively regulates CONSTANS expression and photoperiodic flowering.
pubmed:affiliation
Department of Plant Biology, University of Minnesota, St Paul, 55108, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't