Protein function
Encodes an E3 SUMO protein ligase.
Phenotype
Single mutant: siz1 single mutant is early flowering under both SD and LD conditions.
[Lü¾Œ–”¼zaro et al., 2012][Jin et al., 2008] Function:E3 SUMO protein ligase involved in regulation processes. Mediates SUMO/ attachment to PHR1, a MYB transcriptional activator controlling the phosphate deficiency responses. Functions as an upstream negative regulator of salicylic acid (SA) accumulation and subsequent SA-mediated systemic acquired resistance (SAR) signaling. Probably not involved in jasmonic acid (JA)-mediated defense response. Participates in abiotic stress-induced sumoylation. Controls heat shock-induced SUMO1 and SUMO2 conjugation and facilitates basal thermotolerance. Involved in freezing tolerance by mediating sumoylation of ICE1, a transcription activator of the cold signaling regulator CBF3/DREB1A. Acts as positive regulator of drought stress tolerance. Acts as floral repressor that promotes FLC expression by repressing FLD activity through sumoylation. Acts as negative regulator of abscisic acid (ABA) signaling through ABI5 sumoylation. Mediates sumoylation of SCE1, GTE3 and GTE5.
[Data from UniProt]
Regulators, targets and interactors
Downstream actors
Upstream actors
Protein-protein interactions