InterPro domain: IPR044563

This entry includes protein Sgt1 (Suppressor of G2 allele of SKP1) and its homologues. In budding yeasts, Sgt1 is required for both SCF (Skp1p/Cdc53p-Cullin-F-box)-mediated ubiquitination, cyclic AMP pathway activity and kinetochore function [ 1 ]. Its Schizosaccharomyces pombe homologue, Git7, is required for glucose and cyclic AMP signaling, cell wall integrity, and septation [ 2 ]. Its two homologues in Arabidopsis, SGT1a and SGT1b, can complement two yeast temperature-sensitive sgt1 mutant alleles, suggesting that fundamental cellular function(s) of yeast SGT1in SCF-mediated protein ubiquitylation. Moreover, SGT1a and SGT1b can act as cochaperones with HSP90 and HSC70 and function in regulating multiple resistance (R) genes and environmental responses [ 3 , 4 , 5 , 6 ].

1. Sgt1p contributes to cyclic AMP pathway activity and physically interacts with the adenylyl cyclase Cyr1p/Cdc35p in budding yeast. Eukaryot Cell 1, 568-82
2. Schizosaccharomyces pombe Git7p, a member of the Saccharomyces cerevisiae Sgtlp family, is required for glucose and cyclic AMP signaling, cell wall integrity, and septation. Eukaryot Cell 1, 558-67
3. Regulatory role of SGT1 in early R gene-mediated plant defenses. Science 295, 2077-80
4. The RAR1 interactor SGT1, an essential component of R gene-triggered disease resistance. Science 295, 2073-6
5. Role of SGT1 in the regulation of plant R gene signalling. Microbes Infect 5, 969-76
6. Interaction between SGT1 and cytosolic/nuclear HSC70 chaperones regulates Arabidopsis immune responses. Plant Cell 19, 4061-76