Nucleotide exchange factors (NEFs) are

protein Proteins are large biomolecule , showing alpha helices, represented by ribbons. This poten was the first to have its suckture solved by X-ray crystallography by Max Perutz and Sir John Cowdery Kendrew in 1958, for which they received a No ...

protein

s that stimulate the exchange (replacement) of

nucleoside Nucleosides are glycosylamine 120px, Cyclic hemiaminal ether bond derived from an aldehyde Glycosylamines are a class of biochemical compounds consisting of a Glycosyl, glycosyl group attached to an amine, amino group, -NR2. They are also known ...

diphosphate In chemistry Chemistry is the scientific Science () is a systematic enterprise that builds and organizes knowledge Knowledge is a familiarity or awareness, of someone or something, such as facts A fact is an occurrence in th ...

s for nucleoside triphosphates bound to other proteins.

Function

Many cellular proteins cleave (

hydrolyze Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution Substitution may refer to: Arts and media *Chord substitution, in music, swapping one chord fo ...

) nucleoside triphosphates–

adenosine triphosphate Adenosine triphosphate (ATP) is an organic compound In , organic compounds are generally any s that contain - . Due to carbon's ability to (form chains with other carbon s), millions of organic compounds are known. The study of the properti ...

(ATP) or

guanosine triphosphate Guanosine-5'-triphosphate (GTP) is a purine Purine is a heterocyclic 125px, Pyridine, a heterocyclic compound A heterocyclic compound or ring structure is a cyclic compound that has atoms of at least two different chemical element, elemen ...

(GTP)–to their diphosphate forms (

ADP

and

GDP Gross domestic product (GDP) is a monetary Image:National-Debt-Gillray.jpeg, In a 1786 James Gillray caricature, the plentiful money bags handed to King George III are contrasted with the beggar whose legs and arms were amputated, in the ...

) as a source of energy and to drive conformational changes. These changes in turn affect the structural,

enzymatic Enzymes () are protein Proteins are large biomolecule , showing alpha helices, represented by ribbons. This poten was the first to have its suckture solved by X-ray crystallography by Max Perutz and Sir John Cowdery Kendrew in 1958 ...

, 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.

References

External links

Alfred Wittinghofer's Seminar: GTP-Binding Proteins as Molecular Switches
Proteins Articles containing video clips {{Protein-stub

Function

See also

References

External links