MicroRNA regulation of BAG3.

B-cell lymphoma 2 (Bcl-2)-associated athanogene 3 (BAG3) protein is a member of BAG family of co-chaperones that modulates major biological processes, including apoptosis, autophagy, and development to promote cellular adaptive responses to stress stimuli. Although BAG3 is constitutively expressed in several cell types, its expression is also inducible and is regulated by microRNAs (miRNAs). miRNAs are small non-coding RNAs that mostly bind to the 3'-UTR (untranslated region) of mRNAs to inhibit their translation or to promote their degradation. miRNAs can potentially regulate over 50% of the protein-coding genes in a cell and therefore are involved in the regulation of all major functions, including cell differentiation, growth, proliferation, apoptosis, and autophagy. Dysregulation of miRNA expression is associated with pathogenesis of numerous diseases, including peripheral artery disease (PAD). BAG3 plays a critical role in regulating the response of skeletal muscle cells to ischemia by its ability to regulate autophagy. However, the biological role of miRNAs in the regulation of BAG3 in biological processes has only been elucidated recently. In this review, we discuss how miRNA may play a key role in regulating BAG3 expression under normal and pathological conditions.