What mutation does Photolyase repair?

What mutation does Photolyase repair?

Photolyase, a class of flavoproteins, uses blue light to repair two types of ultraviolet-induced DNA damage, cyclobutane pyrimidine dimer (CPD) and pyrimidine-pyrimidone (6–4) photoproduct (6–4PP).

What types of mutations can intercalating agents lead to?

Intercalating agents, such as acridine, introduce atypical spacing between base pairs, resulting in DNA polymerase introducing either a deletion or an insertion, leading to a potential frameshift mutation.

What type of gene is Photolyases?

Photolyases belong to the cryptochrome/photolyase protein family (CPF) which perform different functions such as DNA repair, circadian photoreceptor, and transcriptional regulation.

Does ethidium bromide cause point mutations?

Combustion products like polycyclic aromatic hydrocarbons are particularly dangerous intercalating agents that can lead to mutation-caused cancers. The intercalating agents ethidium bromide and acridine orange are commonly used in the laboratory to stain DNA for visualization and are potential mutagens.

Does human have photolyase?

The photolyase mechanism is no longer working in humans and other placental mammals who instead rely on the less efficient nucleotide excision repair mechanism, although they do retain many cryptochromes. Photolyases are flavoproteins and contain two light-harvesting cofactors.

Which enzyme is responsible for photoreactivation of DNA?

photolyase
Photoreactivation is a light-induced (300–600 nm) enzymatic cleavage of a thymine dimer to yield two thymine monomers. It is accomplished by photolyase, an enzyme that acts on dimers contained in single- and double-stranded DNA.

What are the three types of point mutations?

There are three types of DNA Mutations: base substitutions, deletions and insertions.

Can induced mutations be repaired?

Recent studies with a model system showed that in vivo repair of preformed lesions (mismatches, abasic sites, single stranded nicks) can in fact induce mutations in flanking DNA. Mismatch repair (MMR) is an essential component for repair-induced mutations, which can occur as distant as 5 kb from the introduced lesions.

Why is ethidium bromide mutagenic?

Because ethidium bromide can bind with DNA, it is highly toxic as a mutagen. It may potentially cause carcinogenic or teratogenic effects, although no scientific evidence showing either health effect has been found.

What happens if you add too much ethidium bromide?

If you have too much EtBr, it could increase the background levels to make it hard to see your band of interest.

What enzyme does mismatch repair?

DNA mismatch repair (MMR) is one of the several DNA repair pathways conserved from bacteria to humans. The primary function of MMR is to eliminate the mismatch of base-base insertions and deletions that appear as a consequence of DNA polymerase errors at DNA synthesis.

Does photoreactivation occur in humans?

Humans and other placental mammals do not seem to have a photoreactivation process, but the gene which codes for photolyase has been conserved and may have evolved to play a role in the excision repair process.