Class I PI 3-kinases are a subgroup of the enzyme family,
phosphoinositide 3-kinase
Phosphoinositide 3-kinases (PI3Ks), also called phosphatidylinositol 3-kinases, are a family of enzymes involved in cellular functions such as cell growth, proliferation, differentiation, motility, survival and intracellular trafficking, which i ...
that possess a common protein domain structure, substrate specificity, and method of activation. Class I PI 3-kinases are further divided into two subclasses, class IA PI 3-kinases and class IB PI 3-kinases.
Class IA PI 3-kinases
Class IA PI 3-kinases are activated by
receptor tyrosine kinases (RTKs).
There are three catalytic subunits that are classified as class IA PI 3-kinases:
*
p110α
*
p110β
Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit beta isoform is an enzyme that in humans is encoded by the ''PIK3CB'' gene.
Phosphoinositide 3-kinases (PI3Ks) phosphorylate the 3-prime OH position of the inositol ring of inositol ...
*
p110δ
There are currently five regulatory subunits that are known to associate with class IA PI 3-kinases catalytic subunits:
*
p85α and
p85β
*
p55α and
p55γ
*
p50α
Class IB PI 3-kinases
Class IB PI 3-kinases are activated by
G-protein-coupled receptors (GPCRs).
The only known class IB PI 3-kinase catalytic subunit is
p110γ
Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit gamma isoform is an enzyme that in humans is encoded by the ''PIK3CG'' gene.
Function
This gene encodes a protein that belongs to the pi3/pi4-kinase family of proteins. The gene p ...
.
There are two known regulatory subunits for p110γ:
*
p101
*p84/
p87PIKAP.
See also
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Phosphoinositide 3-kinase#Class I
*
Phosphoinositide 3-kinase inhibitor
References
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*
*
EC 2.7.1
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