CO-EXPRESSION OF BER AND NER GENES AND TRANSCRIPTION FACTORS IN BRAIN TISSUE
base excision repair; dna excision repair; gene co-expression.
DNA repair pathways are responsible for detecting and correcting damage to the DNA molecule, helping to maintain its integrity. We highlight here the base excision repair pathway (BER), related to the repair of minor DNA base damage, such as those caused by oxidative stress, also acting on neurons and mitochondria, and the nucleotide excision repair pathway (NER), related to the correction of damage that causes distortions in the double helix, such as those caused by ultraviolet radiation. Data indicate that these pathways interact to act in processes related not only to DNA repair, but also to transcriptional regulation of genes with different activities. In order to evaluate the interaction of the two pathways and transcription factors we used a gene co-expression approach using a set of pre-selected genes based on previous studies from our laboratory. We developed a python script that calculated the Pearson correlation coefficient between each pair of genes based on an RNASeq dataset from 13 Gtex Portal brain tissues and used the R pheatmap function, which organized our results into blocks of co-expression. Our results showed positive correlations between the BER and NER pathway genes as well as a set of transcription factors commonly co-expressed with the brain tissue repair genes. These results reinforce the interaction of the two pathways and the participation of NER in neurons and lead us to believe that these co-expressed genes may be acting together in biological processes involving repair and transcription. In addition, the coexpression blocks allowed us to identify co-expressed XPC, XPA, APEX1 and TBP in all tissues, which makes us suppose that these factors may be participating in the same brain tissue interaction complex for each other act in repair or transcription through interaction with TBP.