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Discussion and Conclusions

The requirements of the project were all met. We were able to find the protein and the gene based on our partial amino acid sequence. In addition, we found the structure and function of the protein and its related mutation and diseases.
The Gene
The gene coded by our amino acid sequence is called XPA. This encodes a DNA excision repair protein which functions to repair DNA damaged by ultraviolet rays emitted by the sun, as well as from damage caused by other carcinogens. The gene itself is 22,500 base pairs long. In addition, it has 11 unique isoforms. We focused on two of them, variants ‘a’ and ‘b.’ Variant ‘a’ codes for mRNA, while variant ‘b’ codes for non-coding RNA. Variant ‘a’ has a total of six exons, but variant ‘b’ has seven. This protein is incredibly important to the survival of the organism, repairing damaged DNA. Therefore, the gene is expressed throughout all stages of development.
Protein Structure
The protein structure is one of the most important aspects of the protein. It can help indicate the function, especially when functional domains are found. XPA variant ‘a’ has 122 amino acids and a zinc subdomain with a globular structure. The globular zinc subdomain aids in the overall protein function of DNA excision repair.  The protein has a secondary structure of four helices, a tertiary structure of two sheets, two beta hairpins, five strands, four helices, four helix-helix interactions, sixteen beta turns, and four gamma turns, and no quaternary structures.
Protein Function
The main functions of XPA are DNA excision repair, regulation of autophagy, protein localization to the nucleus, metal ion binding, protein homodimerization, responding to auditory stimulus, responding to oxidative stress, responding to toxic substances, UV-damage excision repair, and overall UV protection. XPA is heavily involved in the platinum drug resistance and nucleotide excision repair biochemical pathways. As for subcellular localization, XPA is most often found within the nucleus. This is due to the fact that its function is to repair DNA and DNAis found in the nucleus. XPA is prolific around the body tissues, and it interacts heavily with the proteins AQR, POLE2, RPA3, RBX1, and PIAS2.
Mutations and Disease Associations
XPA mutations are involved in many different diseases. Given that XPA is designed to repair damaged DNA, many of the related diseases are types of cancer. DNA damage can result in the formation of cancerous tumors. The other disease most associated with XPA mutation is called xeroderma pigmentosum. This is caused by a defect in the XPA gene and results in incredible sensitivity to light.
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