The IPB has once again been recognized for its exemplary actions in terms of equal opportunity-oriented personnel and organizational policies and has received the TOTAL E-QUALITY certification for the…
The Plant Science Student Conference (PSSC) has been organised by students from the two Leibniz institutes, IPK and IPB, every year for the last 20 years. In this interview, Christina Wäsch (IPK) and…
Bagchi, R.; Melnyk, C. W.; Christ, G.; Winkler, M.; Kirchsteiner, K.; Salehin, M.; Mergner, J.; Niemeyer, M.; Schwechheimer, C.; Calderón Villalobos, L. I. A.; Estelle, M.;The Arabidopsis ALF4 protein is a regulator of SCF E3 ligasesEMBO J.37255-268(2018)DOI: 10.15252/embj.201797159
The cullin‐RING E3 ligases (CRLs) regulate diverse cellular processes in all eukaryotes. CRL activity is controlled by several proteins or protein complexes, including NEDD8, CAND1, and the CSN. Recently, a mammalian protein called Glomulin (GLMN) was shown to inhibit CRLs by binding to the RING BOX (RBX1) subunit and preventing binding to the ubiquitin‐conjugating enzyme. Here, we show that Arabidopsis ABERRANT LATERAL ROOT FORMATION4 (ALF4) is an ortholog of GLMN. The alf4 mutant exhibits a phenotype that suggests defects in plant hormone response. We show that ALF4 binds to RBX1 and inhibits the activity of SCFTIR1, an E3 ligase responsible for degradation of the Aux/IAA transcriptional repressors. In vivo, the alf4 mutation destabilizes the CUL1 subunit of the SCF. Reduced CUL1 levels are associated with increased levels of the Aux/IAA proteins as well as the DELLA repressors, substrate of SCFSLY1. We propose that the alf4 phenotype is partly due to increased levels of the Aux/IAA and DELLA proteins.