The ectoderm is induced to become epidermal tissue by BMPs

TLS Online TPP Program

#Id: 10477

#Unit 4. Cell Communication and Cell Signaling

In certain tumors of antibody-producing B lymphocytes, the cyclin D1 gene is translocated & its transcription is

under the control of an antibody-gene enhancer, causing elevated cyclin D1 production.

TLS Online TPP Program

#Id: 10478

#Unit 4. Cell Communication and Cell Signaling

Loss of p16 mimics overproduction of cyclin Ds

TLS Online TPP Program

#Id: 10479

#Unit 4. Cell Communication and Cell Signaling

Loss-of-function mutations in PTC1 permit cell

proliferation in the absence of an Hh signal

TLS Online TPP Program

#Id: 10480

#Unit 4. Cell Communication and Cell Signaling

Multi-hit model

LOF mutations in the tumor suppressors APC and p53 and GOF mutation in the oncogene K-RAS establishing that multiple mutations in the same cell are needed for the cancer to form.

TLS Online TPP Program

#Id: 10481

#Unit 4. Cell Communication and Cell Signaling

p53

tumor-suppressor gene 

arrest of cells with damaged DNA

TLS Online TPP Program

#Id: 10482

#Unit 4. Cell Communication and Cell Signaling

p53

extremely unstable protein and generally does not accumulate to high enough levels to stimulate transcription under normal conditions