E3 ubiquitin-protein ligase RLIM is an enzyme that in humans is encoded by the RLIM gene.

The protein encoded by this gene is a RING-H2 zinc finger protein. It has been shown to be an E3 ubiquitin protein ligase that targets LIM domain binding 1 (LDB1/CLIM), and causes proteasome-dependent degradation of LDB1. This protein and LDB1 are co-repressors of LHX1/LIM-1, a homeodomain transcription factor. Multiple alternatively spliced variants, encoding the same protein, have been identified. [provided by RefSeq].
Function: E3 ubiquitin-protein ligase. Acts as a negative coregulator for LIM homeodomain transcription factors by mediating the ubiquitination and subsequent degradation of LIM cofactors LDB1 and LDB2 and by mediating the recruitment the SIN3a/histone deacetylase corepressor complex. Ubiquitination and degradation of LIM cofactors LDB1 and LDB2 allows DNA-bound LIM homeodomain transcription factors to interact with other protein partners such as RLIM. Plays a role in telomere length-mediated growth suppression by mediating the ubiquitination and degradation of TERF1. Acts as an activator of random inactivation of X chromosome in the embryo, a stochastic process in which one X chromosome is inactivated to minimize sex-related dosage differences of X-encoded genes in somatic cells of female placental mammals.