The genome is the complete set of genes of an organism.

The transcriptome is the complete set of genes expressed under particular conditions.

The proteome is the complete set of polypeptides encoded by the whole genome or produced in any particular cell or tissue

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#Id: 3223

#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

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#Id: 3225

#Unit 4. Cell Communication and Cell Signaling

Benzo(a)pyrene, found in cigarette smoke as well as in coal tar, undergoes metabolic activation by cytochrome P-450 in the lungs to form a potent mutagen.

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#Id: 3227

#Unit 4. Cell Communication and Cell Signaling

P-450 enzymes, modify benzo(a)pyrene in a series of reactions, producing 7,8-diol-9,10-epoxide, a highly potent mutagenic species.

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#Unit 4. Cell Communication and Cell Signaling

7,8-diol-9,10-epoxide is responsible for cancer development forms an adduct with guanine:

(+)-trans-anti-B-(a)-P-N superscript 2-d G adduct

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#Id: 3231

#Unit 4. Cell Communication and Cell Signaling

(+)-trans-anti-B-(a)-P-N superscript 2-d G adduct causes polymerase to insert an A rather than a C opposite the modified G base (Transversion mutation)

TLS Online TPP Program

#Id: 3232

#Unit 4. Cell Communication and Cell Signaling

Potent form of benzo(a)pyrene induces inactivating mutations at codons 175, 248, & 273 of the p53 gene.