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 ...

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 (
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.
See also
*
Nucleoside-diphosphate kinase
*
Guanine nucleotide exchange factor
Guanine nucleotide exchange factors (GEFs) are proteins or protein domains that activate monomeric GTPasesGTPases are a large family of hydrolase enzyme
Enzymes () are proteins that act as biological catalysts (biocatalysts). Catalysts acc ...
References
External links
Alfred Wittinghofer's Seminar: GTP-Binding Proteins as Molecular Switches
Proteins
Articles containing video clips
{{Protein-stub