The Role of Lipase Maturation Factor 2 in Hepatic Steatosis

The Peterfy Laboratory at the College of Osteopathic Medicine of the Pacific, led by Miklos Peterfy, PhD, focuses on genetic and mechanistic determinants of common metabolic diseases, notably obesity, diabetes and dyslipidemia. Central to the lab’s research portfolio is the study of Lipase Maturation Factor 1 (LMF1), an endoplasmic reticulum (ER) chaperone essential for the post-translational activation of key lipases involved in plasma lipid metabolism, including lipoprotein lipase (LPL), hepatic lipase (HL) and endothelial lipase (EL). The lab’s work builds from the discovery of the LMF1 gene in a naturally occurring mutant mouse strain (cld, combined lipase deficient) that exhibits hyperlipidemia due to inactive lipases and impaired triglyceride clearance. These foundational observations link loss of LMF1 function with accumulation of circulating lipids and severe hypertriglyceridemia in both mice and humans, providing a genetic and physiological basis for detailed mechanistic inquiry.

Peterfy’s research strategy integrates genetics, molecular biology, cell biology and in vivo physiology. One major approach exploits naturally occurring genetic variation in mice to identify genes responsible for metabolic phenotypes; another starts from human genetic data, including genome-wide association studies, to nominate candidate genes for functional validation. For LMF1 specifically, the lab pursues tissue-specific knockout mouse models to delineate how LMF1 modulates lipase activity and thereby influences plasma lipid profiles. Complementary biochemical and molecular biological methods are used to identify molecular regulators of LMF1 function, while cell biological approaches investigate potential lipase-independent roles of LMF1 in ER homeostasis. This work addresses not only the folding and maturation of lipases but also the broader ER processes that may impact lipid handling and cellular stress responses.

The laboratory’s publications document both mechanistic insights and translational relevance. Studies from the group describe how LMF1 mutations cause combined lipase deficiency and notable hypertriglyceridemia, and how transgenic expression or genetic variation of Lmf1 affects LPL activity across species. Additional work connects LMF1 induction to ER stress signaling via ATF6α, supporting a role for LMF1 in adaptive ER responses. The lab also engages functional genomic approaches to interpret lipid-associated loci from human GWAS: candidate genes are functionally validated through in vivo overexpression and knockdown studies, with the goal of identifying causal variants and molecular pathways that regulate plasma lipid variation. Published collaborations highlight related lines of inquiry into hepatic lipid handling, insulin sensitivity, and the cellular trafficking processes that intersect with lipase function.