SUMO: Difference between revisions

<StructureSection load='3kyc' size='350' scene='' caption='Human SUMO-1 (yellow) complex with SUMO-activating enzyme subunit 1 (grey),  SUMO-activating enzyme subunit 2 (green), adenosine derivative and Zn+2 ion (grey) (PDB code [[3kyc]])'>

== Function ==

[[SUMO]] is a '''Small Ubiquitin-like MOdifier''' which covalently attaches to cellular proteins to modify their function.  SUMO is similar in structure but not in sequence to [[Ubiquitin|ubiquitin]].  In several organisms SUMO is called SMT3.  The SUMO-conjugating enzyme (E2) is called UBC9.  The sentrin specific protease (SEPN) cleaves the C-terminal peptide from SUMO which then can bind to ubiquitin activating enzyme (E1). For details on SUMO-1 protein complex see <br />

Sumoylation may have a potential role in Alzheimer disease and decrease sumoylation of lamina A is a causative factor in familial dilated cardiomyopathy<ref>PMID:19282183</ref>.

[[Ubiquitin]] (Ub) and ubiquitin-like (Ubl) proteins attached to their target proteins and modulating the activities of those targets in various ways. Three types of evolutionarily conserved enzymes — E1 activating enzymes, E2 conjugating enzymes and E3 ligase enzymes — act sequentially through parallel yet distinct pathways to conjugate ubiquitin and Ubl proteins, such as SUMO and NEDD8, to their targets. The E1 enzyme uses the <scene name='3kyc/Cv/3'>adenosine triphosphate (ATP)</scene> and magnesium to adenylate the C-terminal Ub/Ubl glycine, releasing pyrophosphate and resulting in <scene name='3kyc/Cv/8'>adenosine monophosphate (AMP)</scene>. A non-hydrolysable <scene name='3kyc/Cv/4'>mimic of the acyl adenylate intermediate (AMSN)</scene> and <scene name='3kyc/Cv/5'>mimic of the tetrahedral intermediate (AVSN)</scene> were constructed. In both these compounds the atom of <font color='orange'><b>phosphorus</b></font> is replaced by sulfur (colored <font color='yellow'><b>yellow</b></font>).