The regulation of gene expression in brain
vicissitudes during aging is still not much known and explored. Differential
gene expression and regulation is a key factor involved to identify the
important landmarks within the brain transcriptome to study neuronal aging.
Recently, transcriptomic studies are highly explored to understand and depict
diseased versus normal as next generation sequencing enables to capture the complete biological context to the entire genome. Study
of gene expression during aging compared to young flies provides a signature
and scenario of gene expression and regulation during aging. In this study, we took advantage of NGS raw data of young and old flies head from SRA
database of NCBI and decrypted the gene expression regulation during normal
aging in drosophila model. We identified 350 genes with significant
differential expression between young and old flies having 0.01% FDR. Various
pathways in context to identified genes which are involved in aging include
autophagy i.e. cell death and
apoptosis, proteolysis, oxidative stress, declination grey and white matter and neurotransmitter levels,
mitochondrial discrepancy, electron transport chain, sugar degradation
pathways, activation of transcription factors involved in epigenetic changes,
regulators involved in negative and positive regulation WNT signaling pathways,
G protein coupled receptor etc. as all these factors contribute to
neurodegeneration and possibly dementia in normal aging. So, to find the
specific genes and regulators which are differentially expressed in normal
aging, we investigate brain transcriptome of normal aging flies compared to
young flies which offer a repertoire of genes, regulators and factors involved
in network of neurodegeneration to establish direct correlation between aging
and dementia. We also identified the pathways which are involved in aging and
corresponding gene regulation in these pathways in aging flies brain. It is
found that there are some common pathways whose genes and
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