HSP47 in Mitochondria: Roles in Apoptosis, Signal Transduction, and Protein and Virus Transportation.

Mitochondria are essential organelles for cellular energy production and the regulation of diverse biological processes, including apoptosis, redox homeostasis, and intracellular signaling. Although mitochondrial reactive oxygen species (mtROS) act as critical mediators of these functions, the molecular mechanisms underlying mtROS regulation remain poorly understood. This review summarizes current insights into the role of heat shock protein 47 (HSP47) in mitochondrial oxidative stress and mtROS-mediated cellular responses. In addition to its classical function as an endoplasmic reticulum (ER) chaperone, HSP47 translocates to the mitochondria under oxidative stress conditions. This mitochondrial localization promotes mtROS production, thereby triggering apoptotic pathways and redox-sensitive signal transduction. Furthermore, we examine the mechanistic insights linking HSP47 to mitochondrial function and oxidative stress, highlighting their implications for cellular homeostasis and disease pathogenesis. Overall, these findings establish HSP47 as a novel regulator of mtROS generation, suggesting that the HSP47-mtROS axis represents a promising therapeutic target for oxidative stress-related disorders and a potential role for exploring virus-induced cellular responses in future research.