Dithiothreitol treatment induces heterotypic aggregation of newly synthesized secretory proteins in HepG2 cells.

Selective dye-labeling of newly synthesized proteins in bacterial cells.

We describe fluorescence labeling of newly synthesized proteins in Escherichia coli cells by means of Cu(I)-catalyzed cycloaddition between alkynyl amino acid side chains and the fluorogenic dye 3-azido-7-hydroxycoumarin. The method involves co-translational labeling of proteins by the non-natural amino acids homopropargylglycine (Hpg) or ethynylphenylalanine (Eth) followed by treatment with th...

Fluorescence visualization of newly synthesized proteins in mammalian cells.

Phasic release of newly synthesized secretory proteins in the unstimulated rat exocrine pancreas

Pancreatic lobules from fasted rats secrete pulse-labeled proteins in two phases comprising 15 and 85% of basal output, respectively. The first (0-6.5 h) is initially (less than or equal to 0.5 h) unstimulated by secretagogues, probably represents vesicular traffic of Golgi and post-Golgi origin (including condensing vaculoles/immature granules), and notably contains two groups of polypeptides ...

Secretion of newly synthesized proteins by isolated liver cells.

Suspensions of isolated liver cells were incubated with [3H]leucine as a precursor. The appearance of radioactive albumin and alpha 1-acid glycoprotein in the incubation medium was determined. After about 20 min both albumin and alpha 1-acid glycoprotein were secreted in a linear way. When fucose and galactose were used as radioactive precursors, time lags of about 10 min could be observed.

Regulation of the production of secretory proteins: intracellular degradation of newly synthesized "defective" collagen.

Confluent cultures of human fetal lung fibroblasts degrade approximately 10% of their newly synthesized collagen within the cell prior to secretion. This basal level of intracellular degradation could not be inhibited by colchicine or cytochalasin B, inhibitors of microtubular and microfilament function, respectively, or by N(alpha)-p-tosyl-L-lysine chloromethyl ketone, chloroquine, or NH(4)Cl,...