Arabidopsis RNA-binding protein UBA2a relocalizes into nuclear speckles in response to abscisic acid.
The Arabidopsis thaliana RNA binding protein UBA2a is the closest homologue of the Vicia faba AKIP1 (56% identity). Like AKIP1, UBA2a is a constitutively-expressed nuclear protein and in response to ABA it is also reorganized within the nucleus in "speckles" suggesting a possible role of this protein in the regulation of mRNA metabolism during ABA signaling. AKIP1 interacts with, and is phosphorylated by, the upstream ABA-activated protein kinase AAPK. We have investigated if a pathway similar to that described in Vicia faba also exists in Arabidopsis. Our results showed that despite the resemblance between the corresponding Vicia and Arabidopsis proteins, it appears that the function of UBA2a is independent of OST1 phosphorylation.
Riera
Marta
M
Institut des Sciences du Végétal, Centre National de la Recherche Scientifique UPR2355, Avenue de la Terrasse, 91198 Gif-sur-Yvette, France. mriera@pasteur.fr
Redko
Yulia
Y
Leung
Jeffrey
J
D000040:Abscisic Acid / Q000494:pharmacology*; D021581:Active Transport, Cell Nucleus / Q000187:drug effects / Q000502:physiology; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation / Q000187:drug effects; D010937:Plant Growth Regulators / Q000494:pharmacology*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D011499:Protein Processing, Post-Translational / Q000187:drug effects / Q000502:physiology; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D031307:Vicia faba / Q000235:genetics / Q000378:metabolism
D029681:Arabidopsis Proteins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D016601:RNA-Binding Proteins; D000040:Abscisic Acid; D011494:Protein Kinases; C472139:OST1 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases