Repair of Circumflex Aortic Arch in an Adult

The coronary arteries, originating from the ascending aorta, bifurcate from two sinuses located within the ascending aorta. Positioned just above the aortic semilunar valve, these sinuses house essential aortic baroreceptors and chemoreceptors, crucial for maintaining cardiac function. The left coronary artery and the right coronary artery branch off from the left posterior and anterior aortic sinuses, respectively.
Encircling the heart, the coronary arteries form a ring-like structure before...

Overview

Organisms are capable of detecting and fixing nucleotide mismatches that occur during DNA replication. This sophisticated process requires identifying the new strand and replacing the erroneous bases with correct nucleotides. Mismatch repair is coordinated by many proteins in both prokaryotes and eukaryotes.
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...

In order to be passed through generations, genomic DNA must be undamaged and error-free. However, every day, DNA in a cell undergoes several thousand to a million damaging events by natural causes and external factors. Ionizing radiation such as UV rays, free radicals produced during cellular respiration, and hydrolytic damage from metabolic reactions can alter the structure of DNA. Damages caused include single-base alteration, base dimerization, chain breaks, and cross-linkage.
Chemically...

One of the common DNA damages is the chemical alteration of single bases by alkylation, oxidation, or deamination. The altered bases cause mispairing and strand breakage during replication. This type of damage causes minimal change to the DNA double helix structure and can be repaired by the base excision repair (BER) pathways. BER corrects damaged DNA sequences by removing the damaged base and restoring the original base sequence using the complementary strand as a template.
The first step of...

Overview