Mammalian cells acquire fatty acids (FAs) from dietary sources or via de novo palmitate production by fatty acid synthase (FASN). Although most cells express FASN at low levels, it is upregulated in cancers of the breast, prostate, and liver, among others, and is required during the replication of many viruses, such as dengue virus, hepatitis C, HIV-1, hepatitis B, and severe acute respiratory syndrome coronavirus 2, among others. The precise role of FASN in disease pathogenesis is poorly understood, and whether de novo FA synthesis contributes to host or viral protein acylation has been traditionally difficult to study. Here, we describe a cell-permeable and click chemistry–compatible alkynyl acetate analog (alkynyl acetic acid or 5-hexynoic acid [Alk-4]) that functions as a reporter of FASN-dependent protein acylation. In an FASN-dependent manner, Alk-4 selectively labels the cellular protein interferon-induced transmembrane protein 3 at its known palmitoylation sites, a process that is essential for the antiviral activity of the protein, and the HIV-1 matrix protein at its known myristoylation site, a process that is required for membrane targeting and particle assembly. Alk-4 metabolic labeling also enabled biotin-based purification and identification of more than 200 FASN-dependent acylated cellular proteins. Thus, Alk-4 is a useful bioorthogonal tool to selectively probe FASN-mediated protein acylation in normal and diseased states.
【저자키워드】 IFITM3, Influenza, click chemistry, HIV-1, HA, hemagglutinin, FBS, fetal bovine serum, DMSO, dimethyl sulfoxide, CD9, fatty acid synthase, S-palmitoylation, N-myristoylation, fatty acylation, HIV-1 Gag, Alk-3, 4-pentynoic acid, Alk-4, alkynyl acetic acid or 5-hexynoic acid, Alk-12, alkynyl myristic acid or 13-tetradecynoic acid, Alk-16, alkynyl palmitic acid, or 15-hexadecynoic acid, CTNB1, catenin beta-1, DHHC, aspartate–histidine–histidine–cysteine, FA, fatty acid, FASN, fatty acid synthase, GNA1I, guanine nucleotide-binding protein, alpha inhibiting 1, IFITM3, interferon-induced transmembrane protein 3, IFNβ, interferon beta, KS6A1, ribosomal protein S6 kinase alpha, MA, matrix, SAMHD1, SAM domain and HD domain containing protein 1, 【초록키워드】 viruses, coronavirus, Cancer, Proteins, antiviral activity, Replication, Protein, Hepatitis, membrane, dengue virus, hepatitis B, reporter, liver, function, Fatty acid, Prostate, cellular, Acetate, palmitate, disease pathogenesis, acute respiratory syndrome, Viral protein, Express, purification, transmembrane protein, de novo, FASN, labeling, probe, Host, Cell, required, contribute, upregulated, acetic, fatty, 【제목키워드】 Protein, reporter, fatty,