Comparison Of Aging Genes Between Human And Mouse In Different Tissues

Aging can cause a decline in the human systems and the function of organs,trigger the occurrence and development of various major diseases associated with aging-including cancer,Alzheimer's disease,heart failure,Parkinson's disease,type II diabetes,multiple cardiovascular diseases,coronary heart disease and osteoporosis etc..As a model organism,mice have been widely used in studying human diseases,but at the molecular level,the link between mouse aging and human aging still needs further research.In this thesis,authors compared the age-related gene expression profiles to assess the consistency of human and mouse aging.Furthermore,authors hope that this study will help researchers to judge whether it is reasonable to use mouse as a model organism to do some research on aging and aging-related diseases and drugs prediction.In this thesis,authors compared the aging genes of human and mouse in the gene expression level.The main results are as follows:(1)Reviewing and collecting gene expression big data and matching the human and mouse tissues.In which,two gene expression databases,GTEX and GEO,were adopted,among which GTEX is the latest age-related RNA-Seq tissue database and GEO is the database provided by the National Center for Biotechnology Information(NCBI).By comparing the collected data,authors matched 18 pairs of human and mouse tissues.(2)Differential gene expression analysis.On the one hand,the DESeq2 algorithm was used to perform differential analysis on 15 human tissue data which were collected from the GTEX database.On the other hand,differential analysis was performed on the DNA Microarray gene expression data from 18 mouse tissues and 3 human tissues collected from the GEO database by using the CD algorithm.Finally,authors screened for homologous differential genes in human and mouse and called them "aging genes."(3)Comparative analysis on human and mouse aging genes.On the one hand,authors screened for the same aging genes in human and mouse;on the other hand,Fisher's exact test was used to statistically test the consistency of aging genes between human and mouse tissues.Finally,DAVID(V6.7)and ClueGO(V2.5.1)tools were applied to analyze gene functional enrichment of human and mouse aging genes.Authors found that in 9 pairs of tissues of human and mouse,aging were significantly associated,and authors also found some functions related to aging in human and mouse,such as Phosphoprotein,Cytoplasm,Cell cycle,and GO:0005515?protein Binding and so on.(4)Crosswise comparison of human and mouse aging genes.On the one hand,the same aging genes were screened between tissues in human and mouse separately;on the other hand,Fisher's exact test was used to statistically test the consistency of aging genes between tissues.Finally,four brain-related tissues of human and mouse were compared horizontally.Authors found that human Brain_Cortex and Brain_Hippocampus were significantly correlated in aging,the same conclusion was also found in mouse,and authors found a gene--GFAP--which is related to aging both in human brain and in mouse brain.