Abstract

Brca1 functions in many critical cellular processes such as DNA repair, regulation of transcription, and induction of apoptosis. Due to its immense cellular importance, Brca1 is conserved across many organisms. The protein is in the Zinc finger, C3HC4 type family of proteins. Many proteins in this family are involved in ubiquitination pathways. The phylogeny of Brca1 can be analyzed using a variety of resources. In this study, we chose to utilize NCBI's BLASTP to identify related sequences, Jalview and Muscle to perform sequence alignment, and Phylip to construct a phylogenetic tree. The results demonstrated that the sequences that showed the greatest similarity to the primary Brca1 sequence were the human Brca1 isoforms. Moving outward, the organisms with Brca1 sequences most closely related to the humans were the primates followed by other mammals, marsupials, and birds, respectively. The results of the analysis appear to support our hypothesis that the degree of similarity between BRCA1 sequences from different organisms should follow the accepted evolutionary relationships among the organisms. BRCA1 conservation appears to exist primarily near the N-terminus of the protein in the region containing the functional Zinc-finger domains.

3D Structure of Brca1 (MMDB, NCBI).