Pathways & interactions
DZF domain (IPR006561)
Short name: DZF_dom
This entry represents the DZF domain, which is found exclusively in the metazoa.
- Vertebrate nuclear factor 90 (NF90, also known as ILF3, DRBP76 or NFAR-1), contains two double-stranded RNA-binding motifs (dsRBMs) and interacts with highly structured RNAs as well as the dsRNA-activated protein kinase (PKR).
- Metazoan NF45 (also known as ILF2), appears to function predominantly as a heterodimeric complex with NF90.
- Vertebrate spermatid perinuclear RNA-binding protein (SPNR, also known as STRBP), a testes specific paralogue of NF90.
- Metazoan Zinc-finger protein associated with RNA (Zfr).
Nuclear factors NF90 and NF45 form a protein complex involved in a variety of cellular processes and are thought to affect gene expression both at the transcriptional and translational level. In addition, this complex affects the replication of several viruses through direct interactions with viral RNA. NF90 and NF45 dimerize through their common DZF domain. The DZF domain shows structural similarity to the template-free nucleotidyltransferase family of RNA modifying enzymes. However, the lack of conserved catalytic residues suggests that the DZF domain encodes a 'pseudotransferase' that is no longer able to catalyze transfer of nucleotides.
The DZF dimerisation domain form an oblong structure with a flat face on one side and a curved face on the other. The DZF domain is bipartite and characterised by an N-terminal mixed alpha-beta region that contains a central anti-parallel beta-sheet and a C-terminal alpha-helical region. The overall structure has a pseudo two-fold rotational symmetry.
The central beta-sheet forms the base of a cleft between the N- and C-terminal halves while dimerization is mediated by the alpha-helices at the C terminus [PMID: 22833610].