scholarly journals Inhibition of an active zymogen protease: the zymogen form of matriptase is regulated by HAI-1 and HAI-2

2020 ◽  
Vol 477 (9) ◽  
pp. 1779-1794 ◽  
Author(s):  
Signe Skovbjerg ◽  
Lasse Holt-Danborg ◽  
Annika W. Nonboe ◽  
Zebin Hong ◽  
Ásdís K. Frost ◽  
...  
Keyword(s):  
Serine Proteases ◽  
Active Sites ◽  
Secretory Pathway ◽  
Biological Function ◽  
Significant Activity ◽  
Protein Substrates ◽  
Hepatocyte Growth Factor Activator ◽  
A Cell ◽  
Membrane Bound ◽  
Hepatocyte Growth

The membrane-bound serine protease matriptase belongs to a rare subset of serine proteases that display significant activity in the zymogen form. Matriptase is critically involved in epithelial differentiation and homeostasis, and insufficient regulation of its proteolytic activity directly causes onset and development of malignant cancer. There is strong evidence that the zymogen activity of matriptase is sufficient for its biological function(s). Activated matriptase is inhibited by the two Kunitz-type inhibitor domain-containing hepatocyte growth factor activator inhibitors 1 (HAI-1) and HAI-2, however, it remains unknown whether the activity of the matriptase zymogen is regulated. Using both purified proteins and a cell-based assay, we show that the catalytic activity of the matriptase zymogen towards a peptide-based substrate as well as the natural protein substrates, pro-HGF and pro-prostasin, can be inhibited by HAI-1 and HAI-2. Inhibition of zymogen matriptase by HAI-1 and HAI-2 appears similar to inhibition of activated matriptase and occurs at comparable inhibitor concentrations. This indicates that HAI-1 and HAI-2 interact with the active sites of zymogen and activated matriptase in a similar manner. Our results suggest that HAI-1 and HAI-2 regulate matriptase zymogen activity and thus may act as regulators of matriptase trans(auto)-activation. Due to the main localisation of HAI-2 in the ER and HAI-1 in the secretory pathway and on the cell surface, this regulation likely occurs both in the secretory pathway and on the plasma membrane. Regulation of an active zymogen form of a protease is a novel finding.

scholarly journals Recombinant hepatocyte growth factor activator inhibitor 1: expression inDrosophilaS2 cells, purification and crystallization

2017 ◽  
Vol 73 (1) ◽  
pp. 45-50 ◽  
Author(s):  
Min Liu ◽  
Cai Yuan ◽  
Yunbin Jiang ◽  
Longguang Jiang ◽  
Mingdong Huang
Keyword(s):  
Growth Factor ◽  
Hepatocyte Growth Factor ◽  
Serine Proteases ◽  
Expression System ◽  
Critical Role ◽  
Cell Parameters ◽  
Hepatocyte Growth Factor Activator ◽  
Cell Expression ◽  
Hepatocyte Growth ◽  
Activator Inhibitor

Hepatocyte growth factor activator inhibitor 1 (HAI-1) is a multi-domain membrane-associated protease inhibitor that potently inhibits a variety of serine proteases such as hepatocyte growth factor activator and matriptase. Different truncates of HAI-1 show varying potencies for inhibition of target proteases, suggesting that the domain organization of HAI-1 plays a critical role in its function. Here, the soluble full-length extracellular part of HAI-1 (sHAI-1) was expressed using theDrosophilaS2 insect-cell expression system. Diffraction-quality crystals of sHAI-1 were produced using ammonium sulfate as precipitant. The crystal diffracted to 3.8 Å resolution and belonged to space groupP41212, with unit-cell parametersa=b= 95.42,c= 124.50 Å. The asymmetric unit contains one sHAI-1 molecule.

scholarly journals ITIH4 acts as a protease inhibitor by a novel inhibitory mechanism

2021 ◽  
Vol 7 (2) ◽  
pp. eaba7381
Author(s):  
Rasmus Pihl ◽  
Rasmus K. Jensen ◽  
Emil C. Poulsen ◽  
Lisbeth Jensen ◽  
Annette G. Hansen ◽  
...  
Keyword(s):  
Protease Inhibitor ◽  
Active Sites ◽  
Biological Function ◽  
Inhibitory Mechanism ◽  
Protein Substrates ◽  
Pathological Conditions ◽  
Mannan Binding Lectin ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Binding Lectin

Inter-α-inhibitor heavy chain 4 (ITIH4) is a poorly characterized plasma protein that is proteolytically processed in multiple pathological conditions. However, no biological function of ITIH4 has been identified. Here, we show that ITIH4 is cleaved by several human proteases within a protease-susceptible region, enabling ITIH4 to function as a protease inhibitor. This is exemplified by its inhibition of mannan-binding lectin–associated serine protease-1 (MASP-1), MASP-2, and plasma kallikrein, which are key proteases for intravascular host defense. Mechanistically, ITIH4 acts as bait that, upon cleavage, forms a noncovalent, inhibitory complex with the executing protease that depends on the ITIH4 von Willebrand factor A domain. ITIH4 inhibits the MASPs by sterically preventing larger protein substrates from accessing their active sites, which remain accessible and fully functional toward small substrates. Thus, we demonstrate that ITIH4 functions as a protease inhibitor by a previously undescribed inhibitory mechanism.

scholarly journals The Gut-Brain Axis in Autism Spectrum Disorder: A Focus on the Metalloproteases ADAM10 and ADAM17

2020 ◽  
Vol 22 (1) ◽  
pp. 118
Author(s):  
Yuanpeng Zheng ◽  
Tessa A. Verhoeff ◽  
Paula Perez Pardo ◽  
Johan Garssen ◽  
Aletta D. Kraneveld
Keyword(s):  
Autism Spectrum Disorder ◽  
Intestinal Tract ◽  
Synapse Formation ◽  
Inflammatory Responses ◽  
Repetitive Behavior ◽  
Autism Spectrum ◽  
Spectrum Disorder ◽  
Protein Substrates ◽  
Specific Proteins ◽  
Membrane Bound

Autism Spectrum Disorder (ASD) is a spectrum of disorders that are characterized by problems in social interaction and repetitive behavior. The disease is thought to develop from changes in brain development at an early age, although the exact mechanisms are not known yet. In addition, a significant number of people with ASD develop problems in the intestinal tract. A Disintegrin And Metalloproteases (ADAMs) include a group of enzymes that are able to cleave membrane-bound proteins. ADAM10 and ADAM17 are two members of this family that are able to cleave protein substrates involved in ASD pathogenesis, such as specific proteins important for synapse formation, axon signaling and neuroinflammation. All these pathological mechanisms are involved in ASD. Besides the brain, ADAM10 and ADAM17 are also highly expressed in the intestines. ADAM10 and ADAM17 have implications in pathways that regulate gut permeability, homeostasis and inflammation. These metalloproteases might be involved in microbiota-gut–brain axis interactions in ASD through the regulation of immune and inflammatory responses in the intestinal tract. In this review, the potential roles of ADAM10 and ADAM17 in the pathology of ASD and as targets for new therapies will be discussed, with a focus on the gut–brain axis.

scholarly journals Conjugate of Thiol and Guanidyl Units with Oligoethylene Glycol Linkage for Manipulation of Oxidative Protein Folding

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 879
Author(s):  
Shunsuke Okada ◽  
Motonori Matsusaki ◽  
Masaki Okumura ◽  
Takahiro Muraoka
Keyword(s):  
Protein Folding ◽  
Active Sites ◽  
Biological Process ◽  
Thiol Group ◽  
Native Conformation ◽  
Thiol Compounds ◽  
Oxidative Protein Folding ◽  
Redox Active ◽  
A Cell ◽  
Protein Disulfide

Oxidative protein folding is a biological process to obtain a native conformation of a protein through disulfide-bond formation between cysteine residues. In a cell, disulfide-catalysts such as protein disulfide isomerase promote the oxidative protein folding. Inspired by the active sites of the disulfide-catalysts, synthetic redox-active thiol compounds have been developed, which have shown significant promotion of the folding processes. In our previous study, coupling effects of a thiol group and guanidyl unit on the folding promotion were reported. Herein, we investigated the influences of a spacer between the thiol group and guanidyl unit. A conjugate between thiol and guanidyl units with a diethylene glycol spacer (GdnDEG-SH) showed lower folding promotion effect compared to the thiol–guanidyl conjugate without the spacer (GdnSH). Lower acidity and a more reductive property of the thiol group of GdnDEG-SH compared to those of GdnSH likely resulted in the reduced efficiency of the folding promotion. Thus, the spacer between the thiol and guanidyl groups is critical for the promotion of oxidative protein folding.

scholarly journals Activation of the zymogen of hepatocyte growth factor activator by thrombin.

1993 ◽  
Vol 268 (30) ◽  
pp. 22927-22932
Author(s):  
T Shimomura ◽  
J Kondo ◽  
M Ochiai ◽  
D Naka ◽  
K Miyazawa ◽  
...  
Keyword(s):  
Growth Factor ◽  
Hepatocyte Growth Factor ◽  
Hepatocyte Growth Factor Activator ◽  
Hepatocyte Growth

scholarly journals Activation of the Kexin from Schizosaccharomyces pombeRequires Internal Cleavage of Its Initially Cleaved Prosequence

1998 ◽  
Vol 18 (1) ◽  
pp. 400-408 ◽  
Author(s):  
Dale Powner ◽  
John Davey
Keyword(s):  
Cleavage Site ◽  
Secretory Pathway ◽  
Catalytic Domain ◽  
Activation Process ◽  
Processing Enzymes ◽  
Free Translation ◽  
A Cell ◽  
Internal Site ◽  
Primary Cleavage ◽  
Full Activation

ABSTRACT Members of the kexin family of processing enzymes are responsible for the cleavage of many proproteins during their transport through the secretory pathway. The enzymes themselves are made as inactive precursors, and we investigated the activation process by studying the maturation of Krp1, a kexin from the fission yeastSchizosaccharomyces pombe. Using a cell-free translation-translocation system prepared from Xenopuseggs, we found that Krp1 is made as a preproprotein that loses the presequence during translocation into the endoplasmic reticulum. The prosequence is also rapidly cleaved in a reaction that is autocatalytic and probably intramolecular and is inhibited by disruption of the P domain. Prosequence cleavage normally occurs at Arg-Tyr-Lys-Arg102↓ (primary cleavage site) but can occur at Lys-Arg82 (internal cleavage site) and/or Trp-Arg99 when the basic residues are removed from the primary site. Cleavage of the prosequence is necessary but not sufficient for activation, and Krp1 is initially unable to process substrates presented in trans. Full activation is achieved after further incubation in the extract and is coincident with the addition of O-linked sugars. O glycosylation is not, however, essential for activity, and the crucial event appears to be cleavage of the initially cleaved prosequence at the internal site. Our results are consistent with a model in which the cleaved prosequence remains noncovalently associated with the catalytic domain and acts as an autoinhibitor of the enzyme. Inhibition is then relieved by a second (internal) cleavage of the inhibitory prosequence. Further support for this model is provided by our finding that overexpression of a Krp1 prosequence lacking a cleavable internal site dramatically reduced the growth rate of otherwise wild-type S. pombecells, an effect that was not seen after overexpression of the normal, internally cleavable, prosequence or prosequences that lack the Lys-Arg102 residues.

Sign in / Sign up

Export Citation Format

Share Document