Nucleotide exchange factor 2280725 112402359 2007-03-03T20:51:40Z Arcadian 104523 split out [[Guanine nucleotide exchange factor]] '''Nucleotide exchange factor'''s ('''NEF'''s) are [[protein]]s that stimulate the exchange (replacement) of [[nucleoside]] [[diphosphate]]s for nucleoside [[triphosphate]]s bound to other proteins. ==Function== Many cellular proteins cleave ([[hydrolysis|hydrolyze]]) nucleoside triphosphates–[[adenosine triphosphate]] (ATP) or [[guanosine triphosphate]] (GTP)–to their diphosphate forms ([[adenosine diphosphate|ADP]] and [[guanosine diphosphate|GDP]]) as a source of energy and to drive conformational changes. These changes in turn affect the structural, [[enzyme|enzymatic]], or signalling properties of the protein. Nucleotide exchange factors actively assist in the exchange of depleted nucleoside diphosphates for fresh nucleoside triphosphates. NEFs are specific for the nucleotides they exchange (ADP or GDP, but not both) and are often specific to a single protein or class of proteins with which they interact. ==See also== * [[Nucleoside-diphosphate kinase]] * [[Guanine nucleotide exchange factor]] {{protein-stub}} [[Category:Proteins]]