Mitochondrial membrane potential acts as a retrograde signal to regulate cell cycle progression.

Mitochondria are central to numerous metabolic pathways whereby mitochondrial dysfunction has a profound impact and can manifest in disease. The consequences of mitochondrial dysfunction can be ameliorated by adaptive responses that rely on crosstalk from the mitochondria to the rest of the cell. Such mito-cellular signalling slows cell cycle progression in mitochondrial DNA-deficient (ρ) cells, but the initial trigger of the response has not been thoroughly studied.

Determination of the Ribonucleotide Content of mtDNA Using Alkaline Gels.

Impaired mitochondrial DNA (mtDNA) maintenance, due to, e.g., defects in the replication machinery or an insufficient dNTP supply, underlies a number of mitochondrial disorders.

The integrity and assay performance of tissue mitochondrial DNA is considerably affected by choice of isolation method.

The integrity of mitochondrial DNA (mtDNA) isolated from solid tissues is critical for analyses such as long-range PCR, but is typically assessed under conditions that fail to provide information on the individual mtDNA strands. Using denaturing gel electrophoresis, we show that commonly-used isolation procedures generate mtDNA containing several single-strand breaks per strand. Through systematic comparison of DNA isolation methods, we identify a procedure yielding the highest integrity of mtDNA that we demonstrate displays improved performance in downstream assays.

The PCNA binding domain of Rad2p plays a role in mutagenesis by modulating the cell cycle in response to DNA damage.

The xeroderma pigmentosum group G (XPG) gene, encoding an essential element in nucleotide excision repair (NER), has a proliferating cell nuclear antigen-binding domain (PCNA-BD) at its C-terminal region. However, the role of this domain is controversial because its presence does not affect NER. Using yeast RAD2, a homolog of human XPG, we show that Rad2p interacts with PCNA through its PCNA-BD and the PCNA-BD of Rad2p plays a role in UV-induced mutagenesis.

Yeast RAD2, a homolog of human XPG, plays a key role in the regulation of the cell cycle and actin dynamics.

Mutations in the human XPG gene cause Cockayne syndrome (CS) and xeroderma pigmentosum (XP). Transcription defects have been suggested as the fundamental cause of CS; however, defining CS as a transcription syndrome is inconclusive. In particular, the function of XPG in transcription has not been clearly demonstrated.