Dynorphins are important neuropeptides with a central role in nociception and pain alleviation. Many mechanisms regulate endogenous dynorphin concentrations, including proteolysis. Proprotein convertases (PCs) are widely expressed in the central nervous system and specifically cleave at C-terminal of either a pair of basic amino acids, or a single basic residue. The proteolysis control of endog...

While the importance of modulatory proteolysis in research has steadily increased, knowledge on this process has remained largely disorganized, with the nature and role of entities composing modulatory proteolysis still uncertain. We built CaMPDB, a resource on modulatory proteolysis, with a focus on calpain, a well-studied intracellular protease which regulates substrate functions by proteolyt...

Polyubiquitin chains linked through Lys48 are the principal signal for targeting substrates to the 26S proteasome. Through studies of structurally defined, polyubiquitylated model substrates, we show that tetraubiquitin is the minimum signal for efficient proteasomal targeting. The mechanism of targeting involves a simple increase in substrate affinity that is brought about by autonomous bindin...

Hepatic proteolysis is inhibited by cell swelling following a variety of experimental manoeuvres, such as reduction of extracellular osmolarity, concentrative uptake of amino acids, or blockade of K+ channels by barium. On the other hand, proteolysis is known to be accomplished by pH-sensitive lysosomal proteases. Accordingly, NH3/NH4+ inhibits proteolysis by intralysosomal alkalinization. The ...

1. Hepatocytes were isolated by collagenase perfusion of livers from fed rats and established in stationary monolayer culture. 2. Degradation of intracellular protein was measured in these monolayers after labelling for 16h with [3H]leucine followed by a 3h chase period in medium containing 2mM-leucine. 3. Proteolysis in this system was stimulated by physiological concentrations of glucagon and...

Zena Werb mechanism could explain how the shedding of L-selec-tin and syndecan can occur within minutes upon cell Department of Anatomy University of California, San Francisco stimulation. Through these diverse mechanisms, adhesion , deadhesion, and ECM proteolysis are all brought San Francisco, California 94143-0750 to bear at the leading edge of migrating and invading cells where dynamic chan...

Pyruvate kinase is a key enzyme in glycolytic pathway that catalyzes the transphosphorylation between phosphoenolpyruvate and ADP to yield ATP and Pyruvate. Geobacillus stearothermophillus has a stable pyruvate kinase with determined crystal structure that composed of four separate domains. Given that limited proteolysis experiments can be successfully used to probe conformational features of p...

In complex with the cosubstrate UDP-N-acetylglucosamine (UDP-GlcNAc),O-linked-GlcNAc transferase (OGT) catalyzes Ser/ThrO-GlcNAcylation of many cellular proteins and proteolysis of the transcriptional coregulator HCF-1. Such a dual glycosyltransferase-protease activity, which occurs in the same active site, is unprecedented and integrates both reversible and irreversible forms of protein post-t...

The human cellular prion protein (PrP(C)) is a glycosylphosphatidylinositol (GPI) anchored membrane glycoprotein with two N-glycosylation sites at residues 181 and 197. This protein migrates in several bands by Western blot analysis (WB). Interestingly, PNGase F treatment of human brain homogenates prior to the WB, which is known to remove the N-glycosylations, unexpectedly gives rise to two do...