SUPV3L1 encodes a conserved ATP-dependent RNA helicase that serves as a critical component of mitochondrial RNA metabolism and quality control. The protein functions as the helicase subunit of the mitochondrial degradosome complex, partnering with polynucleotide phosphorylase (PNPase) to degrade double-stranded RNA with 3'-to-5' directionality 1. This degradosome activity is essential for preventing accumulation of mitochondrial double-stranded RNA, which would otherwise escape into the cytoplasm and trigger inappropriate antiviral signaling through the MDA5 pathway 1. SUPV3L1 also rapidly degrades mitochondria-encoded circular RNAs (mecciRNAs) in complex with ELAC2, regulating mitochondrial permeability transition pore function and reactive oxygen species release 2. The protein localizes to discrete mitochondrial translation hubs and helps organize mitochondrial gene expression spatially, with stress conditions triggering formation of RNA-protein bodies that sequester mitochondrial transcripts 3. Loss of SUPV3L1 function results in severe phenotypes including growth retardation, sarcopenia, skin abnormalities, and premature death in mouse models 4. Mutations in SUPV3L1 have been identified as candidate causes of intellectual disability in human patients 5, highlighting its importance for normal cellular function and development.