An a haploid cell secretes the a mating factor and has GPCRs for the α factor on its cell surface; an α cell secretes the α factor and has GPCRs for the a factor.

TLS Online TPP Program

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#Unit 3. Fundamental Processes

Nicking is followed by the action of a specific helicase (UvrD) and one of three exonucleases.

TLS Online TPP Program

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#Unit 3. Fundamental Processes

Eukaryotic cells also repair mismatches and do so using homologs to MutS (called MSH proteins for “MutS homologs”) and MutL (called MLH and PMS

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#Unit 3. Fundamental Processes

In BER, A DNA glycosylase recognizes a damaged base (in this case, a uracil) and cleaves between the base and deoxyribose in the backbone.

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#Unit 3. Fundamental Processes

n BER,  An AP endonuclease cleaves the phosphodiester backbone near the AP site

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#Unit 3. Fundamental Processes

In BER,  DNA polymerase I initiates repair synthesis from the free 3’ hydroxyl at the nick, removing (with its 5’-3’ exonuclease activity) and replacing a portion of the damaged strand. 

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#Unit 3. Fundamental Processes

In BER, The nick remaining after DNA polymerase I has dissociated is sealed by DNA ligase.