IA-2 is a protein-tyrosine phosphatase receptor that upon exocytosis, the cytoplasmic domain is cleaved and moves to the nucleus where it enhances transcription of the insulin gene [1]. The mature exodomain of IA-2 participates in adhesion to the extracellular matrix and is self-proteolyzed in vitro by reactive oxygen species which may be a new shedding mechanism [1].

1: Structure of the mature ectodomain of the human receptor-type protein-tyrosine phosphatase IA-2. Primo ME, Klinke S, Sica MP, Goldbaum FA, Jakoncic J, Poskus E, Ermacora MR; J Biol Chem. 2008;283:4674-4681. PMID:18048354