{PDOC51044} {PS51044; ZF_SP_RING} {BEGIN} ************************************ * Zinc finger SP-RING-type profile * ************************************ SIZ1, SIZ2, and PIAS (protein inhibitor of activated STAT) proteins form a conserved family defined by an unusual RING-related domain, the Siz/PIAS RING finger (SP-RING) [1]. While RING fingers coordinate two Zn2+ ions, with a cross-brace architecture, the SP-RING finger contains only one Zn2+ ion in site B, which is coordinated in a tetrahedral configuration (see ). Three of the four amino acid side chains that coordinate the Zn2+ ion at site A in RING proteins are lacking in Siz/PIAS proteins [2]. Like classical RING fingers SP-RINGs function as an E3 enzyme but specific for sumoylation (see for more details on the ubiquitination pathway). The SP-RING zinc finger has the capacity to interact with Ubc9 (the SUMO specific E2 enzyme) and the substrate and thus can increase the rate of substrate sumoylation [3,4]. Some proteins known to contain an SP-RING zinc finger are listed below: - Mammalian PIAS proteins (PIAS 1,3,x and y). They bind to STAT transcription factors and prevent STAT-activated transcription. The mouse PIAS3 protein has also been called Msx-interacting-zinc finger protein (Miz1) [5]. - Drosophila Su(var)2-10. It is required for proper chromosome structure and chromosome inheritance [6]. - Yeast SIZ1 and SIZ2. They are required for SUMO attachment to the cytoskeletal septin proteins. - Pli1, the unique fission yeast member of the SP-RING family. It is involved in centromeric function. The profile we developed covers the whole SP-RING-type zinc finger. -Sequences known to belong to this class detected by the profile: ALL. -Other sequence(s) detected in Swiss-Prot: NONE. -Note: The SP-RING-type zinc finger is also known as the MIZ-type zinc finger [5]. -Last update: March 2021 / Profile revised. [ 1] Hochstrasser M. "SP-RING for SUMO: new functions bloom for a ubiquitin-like protein." Cell 107:5-8(2001). PubMed=11595179 [ 2] Yunus A.A., Lima C.D. "Structure of the Siz/PIAS SUMO E3 ligase Siz1 and determinants required for SUMO modification of PCNA." Mol. Cell 35:669-682(2009). PubMed=19748360; DOI=10.1016/j.molcel.2009.07.013 [ 3] Johnson E.S., Gupta A.A. "An E3-like factor that promotes SUMO conjugation to the yeast septins." Cell 106:735-744(2001). PubMed=11572779 [ 4] Seeler J.S., Dejean A. "Nuclear and unclear functions of SUMO." Nat. Rev. Mol. Cell Biol. 4:690-699(2003). PubMed=14506472; DOI=10.1038/nrm1200 [ 5] Wu L., Wu H., Ma L., Sangiorgi F., Wu N., Bell J.R., Lyons G.E., Maxson R. "Miz1, a novel zinc finger transcription factor that interacts with Msx2 and enhances its affinity for DNA." Mech. Dev. 65:3-17(1997). PubMed=9256341 [ 6] Hari K.L., Cook K.R., Karpen G.H. "The Drosophila Su(var)2-10 locus regulates chromosome structure and function and encodes a member of the PIAS protein family." Genes Dev. 15:1334-1348(2001). PubMed=11390354; DOI=10.1101/gad.877901 -------------------------------------------------------------------------------- PROSITE is copyrighted by the SIB Swiss Institute of Bioinformatics and distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives (CC BY-NC-ND 4.0) License, see https://prosite.expasy.org/prosite_license.html -------------------------------------------------------------------------------- {END}