title: Lack of SMALL ACIDIC PROTEIN 1 (SMAP1) causes increased sensitivity to an inhibitor of RUB/NEDD8-activating enzyme in Arabidopsis seedlings.
abstract: SMALL ACIDIC PROTEIN 1 (SMAP1) functions upstream of the degradation of AUX/IAA-proteins in the response to 2,4-dichlorophenoxyacetic acid and physically interacts with the COP9 SIGNALOSOME (CSN). Also, its function is linked to RELATED TO UBIQUITIN (RUB) modification. To further investigate the relationship between SMAP1 and the RUB modification system, we examined the effect of MLN4924, an inhibitor of RUB/NEDD8-activating E1 enzyme, on the growth of Arabidopsis thaliana. We found that the anti-auxin resistant 1 mutants, which lack SMAP1, are more sensitive to MLN4924 than wild type and that SMAP1 is responsible for this hypersensitivity. This new evidence supports our previous speculation that SMAP1 acts in Cullin-RING ubiquitin E3 ligase regulated signaling processes via its interaction with components associated with the RUB modification system.
authors.affiliation: Medical and Biotechnological Application Division; Japan Atomic Energy Agency (JAEA); Takasaki, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Oono
authors.forename: Akari
authors.initials: A
authors.lastname: Nakasone
mesh_terms: D017360:Arabidopsis / Q000187:drug effects* / Q000201:enzymology*; D029681:Arabidopsis Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D003517:Cyclopentanes / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D007210:Indoleacetic Acids / Q000378:metabolism; D011743:Pyrimidines / Q000494:pharmacology; D036226:Seedlings / Q000187:drug effects* / Q000378:metabolism*; D014452:Ubiquitins / Q000037:antagonists & inhibitors*
chemical_list: D029681:Arabidopsis Proteins; D003517:Cyclopentanes; D004791:Enzyme Inhibitors; D007210:Indoleacetic Acids; D011743:Pyrimidines; C513170:RUB1 protein, Arabidopsis; C514677:SMAP1 protein, Arabidopsis; D014452:Ubiquitins; C539933:pevonedistat
keywords: MLN4924; Nedd8; RUB; Related to ubiquitin; SMAP1; auxin