Effects of Defective Unloading and Recycling of PCNA Revealed by the Analysis of Mutants.

Timely and complete replication of the genome is essential for life. The PCNA ring plays an essential role in DNA replication and repair by contributing to the processivity of DNA polymerases and by recruiting proteins that act in DNA replication-associated processes. The gene encodes a protein that works, together with the Rfc2-5 subunits (shared by the replication factor C complex), to unload PCNA from chromatin.

Evolutionary Stability Optimizer (ESO): A Novel Approach to Identify and Avoid Mutational Hotspots in DNA Sequences While Maintaining High Expression Levels.

Modern synthetic biology procedures rely on the ability to generate stable genetic constructs that keep their functionality over long periods of time. However, maintenance of these constructs requires energy from the cell and thus reduces the host's fitness. Natural selection results in loss-of-functionality mutations that negate the expression of the construct in the population.

PCNA Loaders and Unloaders-One Ring That Rules Them All.

During each cell duplication, the entirety of the genomic DNA in every cell must be accurately and quickly copied. Given the short time available for the chore, the requirement of many proteins, and the daunting amount of DNA present, DNA replication poses a serious challenge to the cell. A high level of coordination between polymerases and other DNA and chromatin-interacting proteins is vital to complete this task.

DNA damage bypass pathways and their effect on mutagenesis in yeast.

What is the origin of mutations? In contrast to the naïve notion that mutations are unfortunate accidents, genetic research in microorganisms has demonstrated that most mutations are created by genetically encoded error-prone repair mechanisms. However, error-free repair pathways also exist, and it is still unclear how cells decide when to use one repair method or the other. Here, we summarize what is known about the DNA damage tolerance mechanisms (also known as post-replication repair) for perhaps the best-studied organism, the yeast Saccharomyces cerevisiae.