These domains allow ZO-1 to bind to severalother firm junction proteins, including claudin, F-actin, occludin,ZO-2, and ZO-3.36 Our findings show thatZO-1 is reduced in the colitis group and has migrated to the basalregion of the cell, corroborating the study by Poritz (2007).38 The gene discussed is OCLN; the disease is colitis.