title: Effects of missense mutation on structure and function of photoreceptor.
abstract: Phytochromes (PHYs) are photoreceptors of the red (R ~660 nm) and far-red (FR ~730 nm) light, and they control a wide range of responses affecting crucial aspects of plant life. There are five genes PHYA-PHYE encoding for phytochromes of different but overlapping function. One of these, PHYA has the unique function controlling specific responses in high irradiance far-red, as well as in very weak light. Appropriate PHYA functioning requires not only the photoreversibility of molecule but also the proper nuclear localization and degradation of receptor. Recently, we identified and described a mutant PHYA allele (phyA-5) in Arabidopsis thaliana, which showed reduced binding affinity to FHY1/FHL, the proteins regulating its nuclear transport, resulting in impaired nuclear localization and altered signaling under certain conditions. We present here a hypothesis to explain how the identified amino acid substitution may lead to structural changes manifested as altered signaling and phenotype displayed by the phyA-5 mutant.
authors.affiliation: Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary.
authors.forename: Balázs
authors.initials: B
authors.lastname: Leitgeb
authors.forename: Vladyslava
authors.initials: V
authors.lastname: Sokolova
authors.forename: Eberhard
authors.initials: E
authors.lastname: Schäfer
authors.forename: András
authors.initials: A
authors.lastname: Viczián
mesh_terms: D000483:Alleles; D019943:Amino Acid Substitution; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D002467:Cell Nucleus; D017343:Genes, Plant; D008027:Light; D020125:Mutation, Missense; D010641:Phenotype; D010834:Phytochrome / Q000378:metabolism; D051942:Phytochrome A / Q000235:genetics* / Q000378:metabolism; D011485:Protein Binding; D021381:Protein Transport; D015398:Signal Transduction; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; C524723:FHL protein, Arabidopsis; C441269:FHY1 protein, Arabidopsis; D051942:Phytochrome A; D014157:Transcription Factors; D010834:Phytochrome