The FAR1 locus encodes a novel nuclear protein specific to phytochrome A signaling
AUTOR(ES)
Hudson, Matthew
FONTE
Cold Spring Harbor Laboratory Press
RESUMO
The phytochrome family of photoreceptors has a well-defined role in regulating gene expression in response to informational light signals. Little is known, however, of the early steps of phytochrome signal transduction. Here we describe a new Arabidopsis mutant, far1 (far-red-impaired response), which has reduced responsiveness to continuous far-red light, but responds normally to other light wavelengths. This phenotype implies a specific requirement for FAR1 in phyA signal transduction. The far1 locus maps to the south arm of chromosome 4, and is not allelic to photomorphogenic loci identified previously. All five far1 alleles isolated have single nucleotide substitutions that introduce stop codons in a single ORF. The FAR1 gene encodes a protein with no significant sequence similarity to any proteins of known function. The FAR1 protein contains a predicted nuclear localization signal and is targeted to the nucleus in transient transfection assays. This result supports an emerging view that early steps in phytochrome signaling may be centered in the nucleus. The FAR1 gene defines a new multigene family, which consists of at least four genes in Arabidopsis. This observation raises the possibility of redundancy in the phyA-signaling pathway, which could account for the incomplete block of phyA signaling observed in the far1 mutant.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=316922Documentos Relacionados
- Arabidopsis FHY3 defines a key phytochrome A signaling component directly interacting with its homologous partner FAR1
- Nuclear-specific degradation of Far1 is controlled by the localization of the F-box protein Cdc4
- The Arabidopsis thaliana HY1 locus, required for phytochrome-chromophore biosynthesis, encodes a protein related to heme oxygenases
- msg1, a novel melanocyte-specific gene, encodes a nuclear protein and is associated with pigmentation.
- Sucrose Export Defective1 Encodes a Novel Protein Implicated in Chloroplast-to-Nucleus Signaling