cd12441

RNA recognition motif in nucleoporin Nup53 and similar proteins; This subfamily corresponds to the RRM domain of nucleoporin Nup53, also termed mitotic phosphoprotein 44 (MP-44), or nuclear pore complex protein Nup53, required for normal cell growth and nuclear morphology in vertebrate. It tightly associates with the nuclear envelope membrane and the nuclear lamina where it interacts with lamin B. It may also interact with a group of nucleoporins including Nup93, Nup155, and Nup205 and play a role in the association of the mitotic checkpoint protein Mad1 with the nuclear pore complex (NPC). The family also includes Saccharomyces cerevisiae Nup53p, an ortholog of vertebrate nucleoporin Nup53. A unique property of yeast Nup53p is that it contains an additional Kap121p-binding domain and interacts specifically with the karyopherin Kap121p, which is involved in the assembly of Nup53p into NPCs. Both, vertebrate Nup35 and yeast Nup53p, contain an atypical RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), a C-terminal amphipathic alpha-helix and several FG repeats. This family corresponds to the RRM domain which lacks the conserved residues that typically bind RNA in canonical RRM domains.