PRR16 (Largen) is a proline-rich protein that functions as a regulator of mammalian cell size by promoting cell size increase independently of mTOR and Hippo signaling pathways 1. The protein stimulates translation of specific mRNA subsets, particularly those encoding mitochondrial proteins, leading to increased mitochondrial mass and ATP production 1. This translational regulation mechanism links mRNA translation control to mitochondrial function and cell size homeostasis 1. Beyond its primary metabolic role, PRR16 has been associated with several disease contexts. Genome-wide association studies identified PRR16 as a risk locus for anxiety disorders 2 and type 2 diabetes 3, with the latter study noting PRR16's involvement in cardiovascular disease pathways. PRR16 was identified among dysregulated genes in keloid pathogenesis 4 and as a key gene in hepatocellular carcinoma stemness 5. Additionally, PRR16 shows altered DNA methylation patterns in response to prenatal environmental exposures 67, suggesting epigenetic regulation relevant to developmental programming and transgenerational disease susceptibility. These findings indicate PRR16's broader involvement in metabolic diseases and potential as a therapeutic target across multiple pathological conditions.