ERCC3

ERCC3

ERCC3 (Excision Repair Cross-Complementation Group 3) is a gene that encodes a protein involved in the nucleotide excision repair (NER) pathway, which is crucial for repairing DNA damage caused by ultraviolet (UV) light and other mutagens. The ERCC3 protein is also known as the DNA repair helicase XPD, a component of the transcription factor IIH (TFIIH) complex.

Function

ERCC3 plays a vital role in the NER pathway by unwinding DNA around the site of damage, allowing other repair proteins to access and excise the damaged nucleotides. The protein is a helicase, meaning it uses energy derived from ATP hydrolysis to separate DNA strands. This function is essential for both DNA repair and transcription initiation.

Structure

The ERCC3 protein is part of the TFIIH complex, which consists of several subunits, including XPB, XPD, and other associated factors. The XPD helicase activity of ERCC3 is critical for the opening of the DNA double helix during the repair process.

Clinical Significance

Mutations in the ERCC3 gene can lead to several genetic disorders, including:

• Xeroderma Pigmentosum (XP): A condition characterized by extreme sensitivity to UV light, leading to a high risk of skin cancers.
• Trichothiodystrophy (TTD): A disorder that affects multiple systems, including the skin, hair, and nervous system, often resulting in brittle hair and intellectual disability.
• Cockayne Syndrome (CS): A rare disorder characterized by growth failure, neurological degeneration, and photosensitivity.

Research and Implications

Research on ERCC3 and its role in DNA repair has significant implications for understanding cancer development and aging. Defects in the NER pathway, where ERCC3 is a key player, can lead to genomic instability and increased susceptibility to cancer.

See Also

• DNA Repair
• Nucleotide Excision Repair
• Transcription Factor IIH

External Links

• ERCC3 Gene - NCBI
• Genetics Home Reference - ERCC3