Role of DNA Glycosylase in Base-Excision Repair Mechanism

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Which human diseases are associated with mutations in NER genes according to the text?

Diabetes, Hypertension, and Asthma

Huntington's disease, Alzheimer's disease, and Parkinson's disease

Xeroderma pigmentosum (XP), Cockayne Syndrome (CS), and trichothiodystrophy (TTD) (correct)

Leukemia, Lymphoma, and Melanoma

What is a common characteristic of xeroderma pigmentosum (XP) and Cockayne Syndrome (CS)?

No effect on sensitivity to sunlight

Increased sensitivity to sunlight (correct)

Decreased sensitivity to sunlight

Increased resistance to sunlight

How many different NER genes can defects lead to xeroderma pigmentosum?

Three

Five

Ten

Seven (correct)

What is the main function of XPA and XPC in the NER process?

Recognition and excision (D) Signup and view all the answers

What type of breaks are readily repaired using the opposite strand as a template?

Single strand breaks (SSBs) (B) Signup and view all the answers

Which protein coats the single-strand break and protects it from breaking further?

$PARP1$ proteins (A) Signup and view all the answers

What is the role of DNA glycosylase in the BER pathway?

Excise the specific damaged base to generate an AP site (C) Signup and view all the answers

Which type of DNA glycosylase has both glycosylase and AP lyase activities?

Bifunctional DNA glycosylase (A) Signup and view all the answers

How does DNA glycosylase conduct a search for damaged bases on DNA duplexes?

By nonspecifically binding and sliding on the DNA (A) Signup and view all the answers

What is the initial step in the Nucleotide Excision Repair (NER) process?

Cleavage of the phosphodiester backbone (A) Signup and view all the answers

Which factors contribute to the global genomic NER (GG-NER) pathway?

DDB1/DDB2(XPE), HR23B/XPC, XPA/RPA (C) Signup and view all the answers

What distinguishes global genomic NER (GG-NER) from transcription-coupled NER (TC-NER)?

Mode of damage detection (D) Signup and view all the answers

Which proteins are required for the initial detection of DNA damage in transcriptionally active regions during Transcription-Coupled Repair (TCR)?

CSA, CSB, UVSSA (D) Signup and view all the answers

What is the role of the XPF/ERCC1 complex in the Nucleotide Excision Repair (NER) process?

Cleaving 22 nucleotides 5' to the damage (D) Signup and view all the answers

Which DNA repair process results in the formation of an AP site?

Base Excision Repair (BER) (B) Signup and view all the answers

What is the function of RPA in the Nucleotide Excision Repair (NER) pathway?

Remodeling the damaged site (D) Signup and view all the answers

Which proteins play a role in sealing the repaired DNA strand during Nucleotide Excision Repair (NER)?

Ligase anchored to PCNA (D) Signup and view all the answers

What is the final step after the excised oligonucleotide is resynthesized during Nucleotide Excision Repair (NER)?

Sealing by ligase anchored to PCNA (B) Signup and view all the answers