Together with SMCHD1, involved in chromosome X inactivation in females by promoting the compaction of heterochromatin. Also able to repress the ligand-induced transcriptional activity of retinoic acid receptor alpha (RARA), possibly through direct recruitment of histone deacetylases. Interacts with RARA. Interacts with SMCHD1; leading to recruitment to inactivated chromosome X in females. Interacts (via PxVxL motif) with HP1 (CBX1/HP1-beta, CBX3/HP1-gamma and CBX5/HP1-alpha). Localizes to Barr body; recruited by SMCHD1. The Pro-Xaa-Val-Xaa-Leu (PxVxL) motif mediates interaction with HP1 (CBX1/HP1-beta, CBX3/HP1-gamma and CBX5/HP1-alpha). Belongs to the LRIF1 family.