Proteolysis-targeting chimeras (PROTACs) have been explored for the degradation of drug targets for more than two decades. However, only a handful of E3 ligase substrate receptors have been efficiently used. Downregulation and mutation of these receptors would reduce the effectiveness of such PROTACs.
View Article and Find Full Text PDFWith some exceptions, California Assembly Bill 2188 will preclude the use of ∆9-tetrahydrocannabinol-9-carboxylic acid (Δ9-THC-COOH) as a marker of cannabis use in urinary workplace drug testing. The bill allows for the use of psychoactive cannabis markers, which include Δ9-tetrahydrocannabinol (Δ9-THC) and the metabolite 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-Δ9-THC). Both analytes are present in urine mainly as conjugated metabolites and will require hydrolysis prior to analysis, but very little is known about expected concentrations in urine.
View Article and Find Full Text PDFThe RAS isoforms (KRAS, HRAS and NRAS) have distinct cancer type-specific profiles. NRAS mutations are the second most prevalent RAS mutations in skin and hematological malignancies. Although RAS proteins were considered undruggable for decades, isoform and mutation-specific investigations have produced successful RAS inhibitors that are either specific to certain mutants, isoforms (pan-KRAS) or target all RAS proteins (pan-RAS).
View Article and Find Full Text PDFHeterotrimeric G proteins can be regulated by posttranslational modifications, including ubiquitylation. KCTD5, a pentameric substrate receptor protein consisting of an N-terminal BTB domain and a C-terminal domain, engages CUL3 to form the central scaffold of a cullin-RING E3 ligase complex (CRL3) that ubiquitylates Gβγ and reduces Gβγ protein levels in cells. The cryo-EM structure of a 5:5:5 KCTD5/CUL3/Gβγ assembly reveals a highly dynamic complex with rotations of over 60° between the KCTD5/CUL3 and KCTD5/Gβγ moieties of the structure.
View Article and Find Full Text PDFGlycosylation is a critical post-translational protein modification that affects folding, half-life and functionality. Glycosylation is a non-templated and heterogeneous process because of the promiscuity of the enzymes involved. We describe a platform for sequential glycosylation reactions for tailored sugar structures (SUGAR-TARGET) that allows bespoke, controlled N-linked glycosylation in vitro enabled by immobilized enzymes produced with a one-step immobilization/purification method.
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