ARNO, or Cytohesin 2, is a human gene encoded by CYTH2. It may also be known as: Cytohesin-2; ARF exchange factor; ARF nucleotide-binding site opener; Protein ARNO; PH, SEC7 and coiled-coil domain-containing protein 2; CTS18; CTS18.1; PSCD2; PSCD2L; SEC7L; Sec7p-L; Sec7p-like. The encoded protein has an amino acid length of 400 and a mass of 46.5 kDa. Other isoforms may exist. Homologs of this gene exist in other organisms, including: Mouse, Rat, Frog.