The major candidate for the factor that forms the Nieuwkoop center was β-catenin (This multifunctional protein also proved to be a key player in the formation of the dorsal amphibian tissues)

TLS Online TPP Program

#Id: 10431

#Unit 4. Cell Communication and Cell Signaling

SNF5 protein is a core member of SWI/SNF complex. In humans, inactivating somatic SNF5 mutations cause rhabdoid tumors.

TLS Online TPP Program

#Id: 10432

#Unit 4. Cell Communication and Cell Signaling

Carcinogens are mutagens, they act by altering one or more nucleotides in DNA.

TLS Online TPP Program

#Id: 10433

#Unit 4. Cell Communication and Cell Signaling

Carcinogens can be classified into two categories: 

1. Direct-acting carcinogens

2. Indirect-acting carcinogens

TLS Online TPP Program

#Id: 10434

#Unit 4. Cell Communication and Cell Signaling

Direct-acting carcinogens

highly reactive compounds that can react with and modify nucleotide bases in DNA, to distort the normal pattern of base pairing.

TLS Online TPP Program

#Id: 10435

#Unit 4. Cell Communication and Cell Signaling

Direct-carcinogens includes:

Ethylmethane sulfonate (EMS)

Dimethyl sulfate (DMS)

Nitrogen mustards

TLS Online TPP Program

#Id: 10436

#Unit 4. Cell Communication and Cell Signaling

Indirect-acting carcinogens 

Relatively unreactive compounds that become modified to more reactive forms by cellular cytochrome P-450 enzymes