This entails release of DnaC, which allows the DnaB helicase to become active. DnaC hydrolyzes ATP in order to release DnaB. This step marks the transition from initiation to elongation.

TLS Online TPP Program

#Id: 9665

#Unit 4. Cell Communication and Cell Signaling

PI-3 kinase contains SH2 domain which binds to phosphotyrosines on the activated RTKs and cytokine receptors

TLS Online TPP Program

#Id: 9666

#Unit 4. Cell Communication and Cell Signaling

PI-3 kinase adds a phosphate to the 3′ carbon in one of two separate PI substrates, leading to formation of two PI 3-phosphates: PI(3,4)P2 or PI(3,4,5)P3

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#Id: 9667

#Unit 4. Cell Communication and Cell Signaling

In cells, PI-3 kinase pathway :

Triggers cell division 

Prevents apoptosis

Induces specific changes in cell metabolism

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#Id: 9668

#Unit 4. Cell Communication and Cell Signaling

An important signal transduction protein that binds to PI 3-phosphates is protein kinase B (Akt),  a serine/threonine kinase

TLS Online TPP Program

#Id: 9669

#Unit 4. Cell Communication and Cell Signaling

PI-3 kinase was first identified in studies of the 

polyoma virus, a DNA virus

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#Id: 9670

#Unit 4. Cell Communication and Cell Signaling

PKB contains:

A PH domain

A kinase domain