1. Posttranslational modifications of serine protease TMPRSS13 regulate zymogen activation, proteolytic activity, and cell surface localization
- Author
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Fausto A. Varela, Kimberley E. Sala-Hamrick, Jacob R. Mackinder, Karin List, Andrew S. Murray, Carly E. Martin, Evan C. Harrison, and Joseph G. Lundgren
- Subjects
serine protease ,TMPRSS13 ,ERAD, ER-associated degradation system ,Biochemistry ,GPI, glycophosphatidylinositol ,chemistry.chemical_compound ,SRCR, scavenger receptor cysteine rich ,TTSP, type II transmembrane serine protease ,N-linked glycosylation ,L, lipoprotein receptor class A ,Chlorocebus aethiops ,Cellular localization ,Enzyme Precursors ,biology ,Chemistry ,phosphorylation ,type II transmembrane serine protease ,Serine Endopeptidases ,cell surface protein ,Cell biology ,HAI-2 ,Protein Transport ,COS Cells ,Phosphorylation ,lipids (amino acids, peptides, and proteins) ,PNGase F, peptide:N-glycosidase F ,Research Article ,Glycosylation ,Protein domain ,macromolecular substances ,HMW, high molecular weight ,HAI, hepatocyte growth factor activator inhibitor ,protease inhibitor ,ER, endoplasmic reticulum ,PCSK6, proprotein convertase subtilisin/kexin-6 ,Protein Domains ,Zymogen ,Animals ,Humans ,Molecular Biology ,TTSP ,Serine protease ,SP, serine protease ,KLK, kallikrein-related peptidase ,Cell Membrane ,Membrane Proteins ,Cell Biology ,MSPL, mosaic serine protease large-form ,PI-PLC, phosphatidylinositol-specific phospholipase C ,carbohydrates (lipids) ,HEK293 Cells ,Zymogen activation ,Proteolysis ,biology.protein ,HGF, hepatocyte growth factor ,Protein Processing, Post-Translational ,TM, transmembrane - Abstract
TMPRSS13, a member of the type II transmembrane serine protease (TTSP) family, harbors four N-linked glycosylation sites in its extracellular domain. Two of the glycosylated residues are located in the scavenger receptor cysteine-rich (SRCR) protein domain, while the remaining two sites are in the catalytic serine protease (SP) domain. In this study, we examined the role of N-linked glycosylation in the proteolytic activity, autoactivation, and cellular localization of TMPRSS13. Individual and combinatory site-directed mutagenesis of the glycosylated asparagine residues indicated that glycosylation of the SP domain is critical for TMPRSS13 autoactivation and catalytic activity toward one of its protein substrates, the prostasin zymogen. Additionally, SP domain glycosylation-deficient TMPRSS13 displayed impaired trafficking of TMPRSS13 to the cell surface, which correlated with increased retention in the endoplasmic reticulum. Importantly, we showed that N-linked glycosylation was a critical determinant for subsequent phosphorylation of endogenous TMPRSS13. Taken together, we conclude that glycosylation plays an important role in regulating TMPRSS13 activation and activity, phosphorylation, and cell surface localization.
- Published
- 2021