The Ras GTPase Superfamily
These are small monomeric proteins homologous to Ras. They are also called small GTPases. Small GTPases have a molecular weight of about 21 kilodaltons and generally serve as molecular switches for a variety of cellular signaling events. According to their primary amino acid sequences and biochemical properties, the Ras superfamily is further divided into five subfamilies: Ras, Rho, Rab, Arf and Ran. The Rho subfamily is further divided into RHOA, RAC1, and CDC42.
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