Lipase Maturation Factor 1 (LMF1)

Lmf1 RNA was expressed at higher levels in tissues that express little or no lipase activity such as testis and pancreas, suggesting that Lmf1 may have additional functions in these tissues. The Lmf1 protein was predicted to contain 5 transmembrane domains and an evolutionarily conserved domain comprising most of the C-terminal end. Colocalization with calnexin demonstrated that the Lmf1 protein is localized to the endoplasmic reticulum (ER).

The resulting LMF1 truncation, tyr439 to stop (Y439X), removed 127 residues from the C terminus compared with 212 residues eliminated by the cld mutation in the mouse. The Y439X subject showed markedly high plasma triglyceride and had undergone repeated episodes of pancreatitis.