Thus, RanBPM is involved in both nuclear and Quinapril hydrochloride cytoplasmic processes,but how its CP-91149 subcellular localization is regulated has not been characterized. RanBPM is well conserved in mammals, in fact the mouse and human proteins are over 90% identical and their differences fall within the N-terminus.The yeast homolog of RanBPM, called Gid1 or Vid30 was found to be part of an E3 ubiquitin ligase complex that functions to ubiquitinate fructose-1,6-bisphosphatase, a key enzyme in the gluconeogenesis pathway.Recent phylogenetic and sequence analyses revealed that the components of the Gid complex are conserved in eukaryotic genomes, suggesting an ancient and conserved function for this ubiquitin ligase complex in eukaryotes, with RanBPM being one of the most conserved proteins in the complex. In mammalian cells, RanBPM was found in a large cytoplasmic complex together with the mammalian counterparts of all Gid proteins. This complex was named CTLH complex, but is also referred to as the muskelin/RanBPM/CTLH complex.The subunits of the complex are present to different extents in both the cytoplasm and the nucleus, yet how their subcellular localization is regulated is still poorly understood.Domain deletion analyses of RanBPM and complex members Twa1, MAEA and RMND5 a revealed that several domains in each protein contribute differentially to their localization.Previous investigations showed that the muskelin C-terminal domain is important or both RanBPM interaction and cytoplasmic localization, suggesting that RanBPM regulates the subcellular localization of muskelin.However, how the nucleocytoplasmic localization of RanBPM itself is regulated is still largely unknown. Here we have carried out a systematic analysis of RanBPM deletion mutants to investigate the determinants of RanBPM subcellular localization. Our results establish that RanBPM subcellular localization is dependent on several domains/motifs, relying on NLS and NES for direct transport by nucleocytoplasmic transport machinery and on protein domains which may function to retain RanBPM to specific subcellular compartments through interaction with other proteins.