Which is highly associated with the DNA damage?
Extrinsic Damaging Agents. Some of the major extrinsic DNA-damaging threats include ultraviolet (UV) or ionizing (IR) radiation, numerous environmental chemicals, and intended-use chemotherapeutic agents (Table 1). An almost unavoidable environmental exposure is atmospheric radiation.
What are the types of DNA damage?
DNA damage can be subdivided into two types: (1) endogenous damage caused by reactive oxygen species (ROS) that are derived from metabolic byproducts and (2) exogenous damage caused by radiation (UV, X-ray, gamma), hydrolysis, plant toxins, and viruses.
How can you reduce DNA damage?
Regular physical exercise increases antioxidant capacity, protects DNA and reduces the effects of age-related declines in DNA repair. In one study, 16 weeks of physical exercise dramatically increased antioxidant activity, decreased DNA strand breaks and promoted DNA repair.
What are the five main types of DNA damage due to endogenous cellular processes?
DNA bases can be damaged by: (1) oxidative processes, (2) alkylation of bases, (3) base loss caused by the hydrolysis of bases, (4) bulky adduct formation, (5) DNA crosslinking, and (6) DNA strand breaks, including single and double stranded breaks.
What is DNA damage and DNA repair?
At least five major DNA repair pathways—base excision repair (BER), nucleotide excision repair (NER), mismatch repair (MMR), homologous recombination (HR) and non-homologous end joining (NHEJ)—are active throughout different stages of the cell cycle, allowing the cells to repair the DNA damage.
Which of the following is the most common type of DNA damage quizlet?
Base excision repair The oxidation of guanine (8-oxo-guanine) is the most common base damage.
What are three ways that DNA gets damaged?
DNA can be damaged via environmental factors as well. Environmental agents such as UV light, ionizing radiation, and genotoxic chemicals. Replication forks can be stalled due to damaged DNA and double strand breaks are also a form of DNA damage.
What is DNA damage?
DNA damage is a change in the basic structure of DNA that is not itself replicated when the DNA is replicated. A DNA damage can be a chemical addition or disruption to a base of DNA (creating an abnormal nucleotide or nucleotide fragment) or a break in one or both chains of the DNA strands.
How can DNA change or be damaged?
What is endogenous DNA damage?
These mutations arise as mistakes in DNA replication and when DNA polymerases copy damaged templates. The latter result from chemical hydrolysis of nucleoside bases or by reaction of DNA with electrophiles or reactive free radicals generated during metabolism (endogenous DNA damaging agents).
What are the different types of DNA repair?
What is a DNA damage?
How many times does DNA get damaged in a day?
Naturally occurring oxidative DNA damages arise at least 10,000 times per cell per day in humans and as much as 100,000 per cell per day in rats as documented below. Oxidative DNA damage can produce more than 20 types of altered bases as well as single strand breaks.
Which phase of the cell cycle is vulnerable to DNA damage?
During S phase the cell is more vulnerable to DNA damage than any other part of the cell cycle. G2 checkpoint checks for damaged DNA and DNA replication completeness. DNA damage is an alteration in the chemical structure of DNA, such as a break in a strand of DNA, a base missing from the backbone of DNA,…
What happens when DNA is damaged by mutation?
DNA damages cause changes in the structure of the genetic material and prevents the replication mechanism from functioning and performing properly. DNA damage and mutation have different biological consequences. While most DNA damages can undergo DNA repair, such repair is not 100\% efficient.
What happens if a base is damaged during DNA replication?
If a DNA polymerase encounters a damaged DNA base in the template DNA during replication it may place a random nucleotide base across from the lesion. For example, an adenine-containing nucleotide will often be added across a lesion, regardless of what the correct match should be.