Double FYVE-containing protein 1 (DFCP1): isolation, cloning and characterization of a novel FYVE finger protein from a human bone marrow cDNA library.

Double FYVE-containing protein 1 (DFCP1) encodes a 777 amino acid protein that contains: (1) an N-terminal Cys-His cluster with some homology to many zinc finger domains; (2) a consensus sequence consistent with an ATP/GTP binding site; and (3) a C-terminal domain unique because it contains two zinc-binding FYVE domains. The gene, ZNFN2A1 (GenBank accession no. AF251025) was localized to chromosome 14q22-q24 and shown to be composed of 11 exons. Northern blot analysis revealed the presence of three different mRNA transcripts (4.2, 3 and 1.2kb). The two longer transcripts appear to be expressed in a variety of different tissues, especially in endocrine tissues, while the shorter messenger is limited to testis. Both of the larger transcripts are unusual due to the presence of a 463bp long 5' UTR. Furthermore, the 4.2kb transcript contains a non-standard polyadenylation consensus sequence while the 3kb transcript contains a standard consensus sequence but within the open reading frame. Following in vitro transfection of a DFCP1-containing expression construct, confocal microscopy studies showed a vesicular distribution of DFCP1 suggesting that this protein, like other FYVE-containing proteins, might be involved in membrane trafficking.