Ubiquitinconjugating Enzyme H6 (UbcH6), also known as Ubiquitinconjugating Enzyme E2E 1
(UBE2E1), is a ubiquitously expressed protein with a predicted molecular weight of 21 kDa. Human
UbcH6/UBE2E1 shares 99% and 100% amino acid sequence identity with mouse and rat UBE2E1,
respectively. UbcH6/UBE2E1 mediates the selective degradation of shortlived and abnormal proteins.
UbcH6/UBE2E1 catalytic activity is modulated following the addition of the Ubiquitinlike protein ISG15 to
Lys136. In the nucleus, the Nterminal fragment of UbcH6/UBE2E1 interacts with the Ubiquitin ligase
(E3) TRIM21 to mediate substrate ubiquitination. UbcH6/UBE2E1 also interacts with the viral E3,
ICP0, during HSV1 infection. In addition, UbcH6/UBE2E1dependent protein ubiquitination is
implicated in polyglutamine tract disorders such as ataxia.