IndraLab
Statements
"Indeed, ataxin-3 not only deubiquitinated CHIP, but also trimmed Ub conjugates on CHIP substrates, thereby regulating the length of Ub chains."
reach
"Importantly, ataxin-3 deubiquitinates CHIP, terminating CHIP-substrate interaction; polyQ expansion of ataxin-3 increases its affinity for CHIP and decreases CHIP levels in SCA3 mice, suggesting a surprising role for coordinated regulation of CHIP and ataxin-3 as well as dysregulation of this process in SCA3."
reach
"Evidence further supporting this notion that the ability of ataxin-3 to deubiquitinate CHIP is coupled to the ligase activity of CHIP, came from assays in which ataxin-3-mediated deubiquitination of CHIP did not occur until after poly-Ub conjugates on substrate proteins had attained a certain length."
reach
"To determine whether deubiquitination of Ub-CHIP by ataxin-3 requires the presence of ubiquitinated substrate, we performed CHIP ubiquitination reactions with increasing concentrations of HSP90 as substrate, in the presence or absence of ataxin-3 and the chain elongating E2, UbcH5c (XREF_FIG), then assessed the ubiquitin state of CHIP at the end of the reaction."