Mitochondrial RBP Complex AMG-1/SLRP-1 is Required for Germline Development and Reproductive Success in Caenorhabditis elegans

Mitochondria with their own genome (mtDNA) are the powerhouse for many biological processes. The post-transcriptional regulation of mtDNA is conducted by nuclear-encoded mitochondrial RNA-binding proteins (mtRBPs). However, only a few mtRBPs have been characterized. Here, we identified an mtRBP AMG-1 (Abnormal Mitochondria in Germline) which is crucial for the reproductive development especially spermatogenesis in C. elegans. amg-1 mutation caused mitochondrial dysfunction associated with structure defects and disturbed mtDNA transcription in germ cells. Furthermore, AMG-1 deficiency triggers sperm apoptosis and gonadal mitochondrial unfolded protein response non-cell autonomously. SLRP-1 with RNA recognition motif interacts with AMG-1 genetically to regulate germ cell development. AMG-1 is an ortholog of mammalian LRPPRC, whose mutations cause the French-Canadian type of Leigh syndrome (FCLS) characterized by neurodegeneration. Our findings that mtRBP is involved in spermatogenesis by post-transcriptionally regulating mtDNA might provide implications for understanding of the pathogenic mechanisms of FCLS and for the development of mitochondrial medicine.