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Richard S. Johnson

Bio: Richard S. Johnson is an academic researcher from University of Washington. The author has contributed to research in topics: Peptide sequence & Tandem mass spectrometry. The author has an hindex of 41, co-authored 73 publications receiving 12553 citations. Previous affiliations of Richard S. Johnson include Massachusetts Institute of Technology & University of Edinburgh.


Papers
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Journal ArticleDOI
20 Feb 1997-Nature
TL;DR: The results should facilitate the development of therapeutically useful inhibitors of TNF-α release, and they indicate that an important function of adamalysins may be to shed cell-surface proteins.
Abstract: Mammalian cells proteolytically release (shed) the extracellular domains of many cell-surface proteins. Modification of the cell surface in this way can alter the cell's responsiveness to its environment and release potent soluble regulatory factors. The release of soluble tumour-necrosis factor-alpha (TNF-alpha) from its membrane-bound precursor is one of the most intensively studied shedding events because this inflammatory cytokine is so physiologically important. The inhibition of TNF-alpha release (and many other shedding phenomena) by hydroxamic acid-based inhibitors indicates that one or more metalloproteinases is involved. We have now purified and cloned a metalloproteinase that specifically cleaves precursor TNF-alpha. Inactivation of the gene in mouse cells caused a marked decrease in soluble TNF-alpha production. This enzyme (called the TNF-alpha-converting enzyme, or TACE) is a new member of the family of mammalian adamalysins (or ADAMs), for which no physiological catalytic function has previously been identified. Our results should facilitate the development of therapeutically useful inhibitors of TNF-alpha release, and they indicate that an important function of adamalysins may be to shed cell-surface proteins.

3,007 citations

Journal ArticleDOI
13 Nov 1998-Science
TL;DR: The phenotype of mice lacking TACE suggests an essential role for soluble TGFalpha in normal development and emphasizes the importance of protein ectodomain shedding in vivo.
Abstract: The ectodomains of numerous proteins are released from cells by proteolysis to yield soluble intercellular regulators. The responsible protease, tumor necrosis factor-alpha converting enzyme (TACE), has been identified only in the case when tumor necrosis factor-alpha (TNFalpha) is released. Analyses of cells lacking this metalloproteinase-disintegrin revealed an expanded role for TACE in the processing of other cell surface proteins, including a TNF receptor, the L-selectin adhesion molecule, and transforming growth factor-alpha (TGFalpha). The phenotype of mice lacking TACE suggests an essential role for soluble TGFalpha in normal development and emphasizes the importance of protein ectodomain shedding in vivo.

1,627 citations

Journal ArticleDOI
TL;DR: The identification of a distinct receptor for TRAIL, TRAIL‐R2, by ligand‐based affinity purification and subsequent molecular cloning suggests an unexpected complexity to TRAIL biology, reminiscent of dual receptors for TNF, the canonical member of this family.
Abstract: TRAIL is a member of the tumor necrosis factor (TNF) family of cytokines and induces apoptosis in a wide variety of cells. Based on homology searching of a private database, a receptor for TRAIL (DR4 or TRAIL-R1) was recently identified. Here we report the identification of a distinct receptor for TRAIL, TRAIL-R2, by ligand-based affinity purification and subsequent molecular cloning. TRAIL-R2 was purified independently as the only receptor for TRAIL detectable on the surface of two different human cell lines that undergo apoptosis upon stimulation with TRAIL. TRAIL-R2 contains two extracellular cysteine-rich repeats, typical for TNF receptor (TNFR) family members, and a cytoplasmic death domain. TRAIL binds to recombinant cell-surface-expressed TRAIL-R2, and TRAIL-induced apoptosis is inhibited by a TRAIL-R2-Fc fusion protein. TRAIL-R2 mRNA is widely expressed and the gene encoding TRAIL-R2 is located on human chromosome 8p22-21. Like TRAIL-R1, TRAIL-R2 engages a caspase-dependent apoptotic pathway but, in contrast to TRAIL-R1, TRAIL-R2 mediates apoptosis via the intracellular adaptor molecule FADD/MORT1. The existence of two distinct receptors for the same ligand suggests an unexpected complexity to TRAIL biology, reminiscent of dual receptors for TNF, the canonical member of this family.

1,190 citations

Journal ArticleDOI
TL;DR: It is demonstrated that TACE (tumor necrosis factor α converting enzyme), a member of the ADAM family (a disintegrinand metalloprotease-family) of proteases, plays a central role in regulated α-cleavage of APP.

912 citations

Journal ArticleDOI
TL;DR: In this paper, the collision (10 keV)-induced decomposition (CID) of (M + H)+ ions of peptides generated by fast atom bombardment ionization has been studied in a tandem mass spectrometer consisting of two consecutive double-focussing analyzers.

476 citations


Cited by
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Journal ArticleDOI
TL;DR: Atherosclerosis is an inflammatory disease as discussed by the authors, and it is a major cause of death in the United States, Europe, and much of Asia, despite changes in lifestyle and use of new pharmacologic approaches to lower plasma cholesterol concentrations.
Abstract: Atherosclerosis is an inflammatory disease. Because high plasma concentrations of cholesterol, in particular those of low-density lipoprotein (LDL) cholesterol, are one of the principal risk factors for atherosclerosis,1 the process of atherogenesis has been considered by many to consist largely of the accumulation of lipids within the artery wall; however, it is much more than that. Despite changes in lifestyle and the use of new pharmacologic approaches to lower plasma cholesterol concentrations,2,3 cardiovascular disease continues to be the principal cause of death in the United States, Europe, and much of Asia.4,5 In fact, the lesions of atherosclerosis represent . . .

19,881 citations

Journal Article
TL;DR: Despite changes in lifestyle and the use of new pharmacologic approaches to lower plasma cholesterol concentrations, cardiovascular disease continues to be the principal cause of death in the United States, Europe, and much of Asia.

9,749 citations

Journal ArticleDOI
TL;DR: The approach described in this manuscript provides a convenient method to interpret tandem mass spectra with known sequences in a protein database.

6,317 citations

Journal ArticleDOI
28 Aug 1998-Science
TL;DR: Apoptosis is a cell suicide mechanism that enables metazoans to control cell number in tissues and to eliminate individual cells that threaten the animal's survival.
Abstract: Apoptosis is a cell suicide mechanism that enables metazoans to control cell number in tissues and to eliminate individual cells that threaten the animal's survival. Certain cells have unique sensors, termed death receptors, on their surface. Death receptors detect the presence of extracellular death signals and, in response, they rapidly ignite the cell's intrinsic apoptosis machinery.

5,968 citations

Journal ArticleDOI
TL;DR: It is shown that the MMPs have functions other than promotion of invasion, have substrates other than components of the extracellular matrix, and that they function before invasion in the development of cancer.
Abstract: Matrix metalloproteinases (MMPs) have long been associated with cancer-cell invasion and metastasis. This provided the rationale for clinical trials of MMP inhibitors, unfortunately with disappointing results. We now know, however, that the MMPs have functions other than promotion of invasion, have substrates other than components of the extracellular matrix, and that they function before invasion in the development of cancer. With this knowledge in hand, can we rethink the use of MMP inhibitors in the clinic?

5,860 citations