Like the Lambda repressor, the cII protein is a transcriptional activator. It binds to a site upstream of a promoter called PRE (for repressor establishment) and stimulates transcription of the cI (repressor) gene from that promoter.

TLS Online TPP Program

#Id: 9650

#Unit 4. Cell Communication and Cell Signaling

Mammalian MAP kinases include  Jun N-terminal kinases and p38 kinases, which are activated by signaling pathways in response to various types of stresses

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#Id: 9651

#Unit 4. Cell Communication and Cell Signaling

Phosphorylation by MEK at Y-185 and T-183 in activation loop of MAP kinase leads to a marked conformational change & promotes MAP kinase activation and dimerization.

TLS Online TPP Program

#Id: 9652

#Unit 4. Cell Communication and Cell Signaling

TLS Online TPP Program

#Id: 9653

#Unit 4. Cell Communication and Cell Signaling

Activated dimeric MAP kinase induces transcription of the c-fos gene by directly activating TCF, and indirectly activating SRF.

TLS Online TPP Program

#Id: 9654

#Unit 4. Cell Communication and Cell Signaling

Feedback regulation by MAP Kinase

activated MAP kinase phosphorylates the HER1 on a threonine residue near the juxtamembrane domain. 

TLS Online TPP Program

#Id: 9655

#Unit 4. Cell Communication and Cell Signaling

Feedback regulation by MAP Kinase

Phosphorylation of threonine residue in HER1 decreases the ability of the receptor kinase to become fully active.