SMG1 is a family of eukaryotic proteins. In humans this family acts as an mRNA-surveillance protein [1,2]. In C.elegans, SMG1, a phosphatidylinositol kinase-related protein kinase, is a key regulator of growth. Loss of SMG1 leads to hyperactive responses to injury and subsequent growth that continues out of control. It has an antagonistic role to mTOR signalling in these worms [3] and possibly also in higher eukaryotes.

1: Cloning of a novel phosphatidylinositol kinase-related kinase: characterization of the human SMG-1 RNA surveillance protein. Denning G, Jamieson L, Maquat LE, Thompson EA, Fields AP; J Biol Chem. 2001;276:22709-22714. PMID:11331269

2: The mRNA surveillance protein hSMG-1 functions in genotoxic stress response pathways in mammalian cells. Brumbaugh KM, Otterness DM, Geisen C, Oliveira V, Brognard J, Li X, Lejeune F, Tibbetts RS, Maquat LE, Abraham RT; Mol Cell. 2004;14:585-598. PMID:15175154

3: SMG-1 is a phosphatidylinositol kinase-related protein kinase required for nonsense-mediated mRNA Decay in Caenorhabditis elegans. Grimson A, O'Connor S, Newman CL, Anderson P; Mol Cell Biol. 2004;24:7483-7490. PMID:15314158

4: SMG-1 and mTORC1 act antagonistically to regulate response to injury and growth in planarians. Gonzalez-Estevez C, Felix DA, Smith MD, Paps J, Morley SJ, James V, Sharp TV, Aboobaker AA; PLoS Genet. 2012;8:e1002619. PMID:22479207