Transcription factor motif activity as a biomarker of muscle aging

In prior work, we analyzed gene expression profiles of mouse, rat and human gastrocnemius muscles to identify conserved regulators of muscle aging processes. By further comparing data obtained from different muscles we found stronger conservation of aging-related factors at the level of molecular pathways than at the level of individual genes. Here we compared the predictive power of models based on gene expression levels and those based on transcription factor motif activities for an individual's age. Although somewhat less accurate than models based on gene expression, models based on motif activities achieve good prediction of muscle age, further providing insights into aging-related molecular pathways.