XRCC3

XRCC3

XRCC3 (X-ray repair cross-complementing protein 3) is a human gene that encodes a protein involved in the repair of DNA double-strand breaks by homologous recombination. This protein is a member of the RAD51 family, which plays a crucial role in maintaining genomic stability by facilitating the accurate repair of DNA damage.

Function

XRCC3 is essential for the repair of DNA double-strand breaks, which can occur due to exposure to ionizing radiation, oxidative stress, or during normal cellular processes such as DNA replication. The XRCC3 protein interacts with other RAD51 family members to form a complex that assists in the homologous recombination repair pathway. This pathway is critical for error-free repair of double-strand breaks, thereby preventing chromosomal aberrations and maintaining genomic integrity.

Structure

The XRCC3 protein is composed of several domains that are characteristic of the RAD51 family, including a Walker A and Walker B motif, which are involved in ATP binding and hydrolysis. These domains are crucial for the protein's function in DNA repair, as they facilitate the formation of nucleoprotein filaments necessary for homologous pairing and strand exchange.

Clinical Significance

Mutations or polymorphisms in the XRCC3 gene have been associated with an increased risk of various cancers, including breast cancer, melanoma, and bladder cancer. Studies have shown that individuals with certain XRCC3 variants may have a reduced capacity to repair DNA damage, leading to increased susceptibility to cancer. Additionally, XRCC3 is being investigated as a potential biomarker for predicting the response to certain chemotherapeutic agents that induce DNA damage.

Research

Ongoing research is focused on understanding the precise mechanisms by which XRCC3 and its interacting partners facilitate homologous recombination. There is also interest in developing therapeutic strategies that target XRCC3 and related pathways to enhance the efficacy of cancer treatments.

Also see

• DNA repair
• Homologous recombination
• RAD51
• Genomic stability
• Cancer genetics