The product of this gene is a mitogen induced GTPase activating protein (GAP). It exhibits a specific GAP activity for Ras-related regulatory proteins Rap1 and Rap2, but not for Ran or other small GTPases. This protein may also hamper mitogen-induced cell cycle progression when abnormally or prematurely expressed. It is localized to the perinuclear region. Two alternatively spliced variants encoding the same isoform have been characterized to date. [provided by RefSeq, Jul 2008].
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Hattori, Tsukamoto, Nur-e-Kamal, Rubinfeld, Iwai, Kubota, Maruta, Minato: "Molecular cloning of a novel mitogen-inducible nuclear protein with a Ran GTPase-activating domain that affects cell cycle progression." in: Molecular and cellular biology, Vol. 15, Issue 1, pp. 552-60, (1995) (PubMed).