The Functional Role of Membrane Bound Proteinase 3

The possible functional role of vesicles and crystal-containing microbodies in the production of oxalate, endopolygalacturonase, or cellulase by Sclerotinia sclerotiorum was investigated. The presence of multivesicular bodies in hyphal tips was not correlated with secretion or production of oxalate or these extracellular hydrolases. More crystal-containing microbodies were present in hyphal tips grown on media which supported greater extracellular enzyme production. No correlation existed between numbers of crystal-containing microbodies in hyphal tips and production of oxalate. Numerous membrane-bound vesicles (0.09–0.18 µm diam) were associated with tips grown on a D-glucose–Na succinate medium which supported high production of oxalate. The general ultrastructural organization of these hyphal tips was similar to that reported for other ascomycetes. Differences in numbers and distributions of organelles were observed between hyphal tips and older hyphae as well as between hyphal tips grown on the different carbon sources.

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Functional role of membrane-bound adenylyl cyclases and coupled to them receptors and G-proteins in regulation of fertility of spermatozoa

Journal of Evolutionary Biochemistry and Physiology ◽

10.1134/s0022093014040024 ◽

2014 ◽

Vol 50 (4) ◽

pp. 286-302

Author(s):

A. O. Shpakov ◽

K. V. Derkach

Keyword(s):

G Proteins ◽

Functional Role ◽

Adenylyl Cyclases ◽

Membrane Bound

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A membrane-bound plastid inclusion in the epidermis of leaves of Taraxacum officinale

Canadian Journal of Botany ◽

10.1139/b77-031 ◽

1977 ◽

Vol 55 (2) ◽

pp. 222-225 ◽

Cited By ~ 3

Author(s):

E. S. Martin ◽

G. Larbalestier

Keyword(s):

Inclusion Bodies ◽

Functional Role ◽

Taraxacum Officinale ◽

Single Membrane ◽

Membrane Bound ◽

Dense Inclusion ◽

Electron Dense Inclusion

Epidermal chloroplasts of Taraxacum officinale agg. contain large electron-dense inclusion bodies enclosed by a single membrane. These inclusion bodies were not observed in mesophyll chloroplasts. The origin and functional role of these structures is discussed.

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Measurement of free and membrane-bound cathepsin G in human neutrophils using new sensitive fluorogenic substrates

Biochemical Journal ◽

10.1042/bj20020321 ◽

2002 ◽

Vol 366 (3) ◽

pp. 965-970 ◽

Cited By ~ 25

Author(s):

Sylvie ATTUCCI ◽

Brice KORKMAZ ◽

Luiz JULIANO ◽

Eric HAZOUARD ◽

Catherine GIRARDIN ◽

...

Keyword(s):

Cathepsin G ◽

Polymorphonuclear Neutrophils ◽

Human Neutrophils ◽

Proteinase 3 ◽

Protein Targets ◽

Peptide Substrates ◽

Loop Sequence ◽

Membrane Bound

Activated human polymorphonuclear neutrophils at inflammatory sites release the chymotrypsin-like protease cathepsin G, together with elastase and proteinase 3 (myeloblastin), from their azurophil granules. The low activity of cathepsin G on synthetic substrates seriously impairs studies designed to clarify its role in tissue inflammation. We have solved this problem by producing new peptide substrates with intramolecularly quenched fluorescence. These substrates were deduced from the sequence of putative protein targets of cathepsin G, including the reactive loop sequence of serpin inhibitors and the N-terminal domain of the protease-activated receptor of thrombin, PAR-1. Two substrates were selected, Abz-TPFSGQ-EDDnp and Abz-EPFWEDQ-EDDnp, that are cleaved very efficiently by cathepsin G but not by neutrophil elastase or proteinase 3, with specificity constants (kcat/Km) in the 105M-1·s-1 range. They can be used to measure subnanomolar concentrations of free enzyme in vitro and at the surface of neutrophils purified from fresh human blood. Purified neutrophils express 0.02—0.7pg of cathepsin G/cell (n = 15) at their surface. This means that about 104 purified cells may be enough to record cathepsin G activity within minutes. This may be most important for investigating the role of cathepsin G as an inflammatory agent, especially in bronchoalveolar lavage fluids from patients with pulmonary inflammatory disorders.

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MBTPS2, a membrane bound protease, underlying several distinct skin and bone disorders

Journal of Translational Medicine ◽

10.1186/s12967-021-02779-5 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Natarin Caengprasath ◽

Thanakorn Theerapanon ◽

Thantrira Porntaveetus ◽

Vorasuk Shotelersuk

Keyword(s):

Functional Role ◽

Cholesterol Homeostasis ◽

Regulatory Proteins ◽

Osteogenesis Imperfecta Type ◽

Keratosis Follicularis ◽

Cellular Processes ◽

Unfolded Protein ◽

Human Disorders ◽

Membrane Bound

AbstractThe MBTPS2 gene on the X-chromosome encodes the membrane-bound transcription factor protease, site-2 (MBTPS2) or site-2 protease (S2P) which cleaves and activates several signaling and regulatory proteins from the membrane. The MBTPS2 is critical for a myriad of cellular processes, ranging from the regulation of cholesterol homeostasis to unfolded protein responses. While its functional role has become much clearer in the recent years, how mutations in the MBTPS2 gene lead to several human disorders with different phenotypes including Ichthyosis Follicularis, Atrichia and Photophobia syndrome (IFAP) with or without BRESHECK syndrome, Keratosis Follicularis Spinulosa Decalvans (KFSD), Olmsted syndrome, and Osteogenesis Imperfecta type XIX remains obscure. This review presents the biological role of MBTPS2 in development, summarizes its mutations and implicated disorders, and discusses outstanding unanswered questions.

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