 |
|
Glue inside the cell: Ubiquitin builds up an immune response
October 22, 2007Ubiquitin is a small protein, which can be attached to other cellular proteins, a process known as ubiquitination. Discoveries in the 1980 th on a key function of ubiquitination in the regulation of protein degradation where awarded with the Nobel Prize for chemistry in 2004. A study headed by the Junior Group of Dr. Daniel Krappmann (GSF - National Research Center for Environment and Health, Institute of Toxicology) in collaboration with Dr. Jürgen Ruland (TU Munich) and Dr. Claus Scheidereit ( Max-Delbrück-Center , Berlin ) now reports a novel finding about ubiquitination as a key event for the activation of an immune response. (EMBO J. AOP, 18.10.2007).
The acquired immune response is triggered after specific engagement of foreign peptides (antigens) by receptor molecules on white blood cell (lymphocytes). Cellular signaling pathways are responsible for the activation of lymphocytes. Krappmann and co-workers present evidence, that in T cells, which constitute a subgroup of lymphocytes, ubiquitin is attached to the Malt1 protein in response to antigen stimulation. Malt1 is part of the CBM (Carma1-Bcl10-Malt1) complex that constitutes a crucial switch for the activation of the immune defense. Using biochemical, molecular and genetic techniques the scientists could prove that this novel Malt1 ubiquitination is an essential step in the regulation of T cell activation.
'Mechanistically, ubiquitin is virtually acting as all-purpose glue that links different protein components inside the cell', Krappmann explains. 'However, ubiquitination provides an important advantage compared to conventional adhesives: It is reversible, meaning that the associations can be resolved'.
This process of de-ubiquitination is constantly happening in cells and it could contribute to prevent an over-shooting activation of T cells. Unopposed lymphocyte activity is responsible for many chronic diseases, autoimmunity or even lymphoma development. Future work must address the status of Malt1 ubiquitination under pathological conditions, for instance in Malt1 dependent lymphomas. By this the scientists hope to demonstrate the potential of targeting the ubiquitin system for the development of novel therapeutic approaches.
GSF - National Research Center for Environment and Health
This process of de-ubiquitination is constantly happening in cells and it could contribute to prevent an over-shooting activation of T cells. Unopposed lymphocyte activity is responsible for many chronic diseases, autoimmunity or even lymphoma development. Future work must address the status of Malt1 ubiquitination under pathological conditions, for instance in Malt1 dependent lymphomas. By this the scientists hope to demonstrate the potential of targeting the ubiquitin system for the development of novel therapeutic approaches.
GSF - National Research Center for Environment and Health
Ubiquitin News and Current Ubiquitin Events RSSResearchers discover how rheumatoid arthritis causes bone loss
Researchers have discovered key details of how rheumatoid arthritis (RA) destroys bone, according to a study published in the Aug. 22 edition of the Journal of Biological Chemistry.
Model for Angelman syndrome developed by University of Texas at Austin biologists
A model for studying the genetics of Angelman syndrome, a neurological disorder that causes mental retardation and other symptoms in one out of 15,000 births, has been developed by biologists at The University of Texas at Austin.
Water is 'designer fluid' that helps proteins change shape, scientists say
Ubiquitous on Earth, water also has been found in comets, on Mars and in molecular clouds in interstellar space. Now, scientists say this common fluid is not as well understood as we thought.
Cold Spring Harbor Scientists Reveal A Protein's Role in Enabling AIDS Virus to Reproduce
A team of scientists at Cold Spring Harbor Laboratory (CSHL) has discovered new details about how a simian strain of the AIDS virus replicates.
Penn scientists find a protein that inhibits Ebola from reaching out to infect neighboring cells
Scientists at the University of Pennsylvania School of Veterinary Medicine have identified a protein, ISG15, that inhibits the Ebola virus from budding, the process by which viruses escape from cells and spread to infect neighboring cells.
Oncoproteins double-team and destroy vital tumor-suppressor
Two previously unconnected cancer-promoting proteins team up to ambush a critical tumor suppressor by evicting it from the cell's nucleus and then marking it for death by a protein-shredding mechanism, a team led by scientists at The University of Texas M. D. Anderson Cancer Center reports in the Feb. 10 issue of Nature Cell Biology.
Quality control mechanism tags defective sperm cells inside the body
Defective sperm cells do not pass through the body unnoticed. A new University of Missouri study provides evidence that the body recognizes and tags defective sperm cells while they undergo maturation in the epididymis, a sperm storage gland attached to the testis.
St. Jude finds mechanism for faulty protein disposal
A discovery by St. Jude Children's Research Hospital scientists offers new insights into how myeloma cells dispose of defective or excess proteins and could lead to new cancer treatments.
Gene expression profiling of dengue virus infection in cell lines and patients
Researchers at the Novartis Institute for Tropical Diseases and the Genome Institute of Singapore have identified new host genes associated with dengue virus infection, which may open new avenues to developing a drug to treat the disease.
Discovery of new protein could provide new understanding of male fertility
Scientists have discovered a new enzyme involved in the degradation of proteins inside cells, a process that helps eliminate or recycle proteins that are no longer needed.
More Ubiquitin News Articles
 | Methods in Enzymology, Volume 399: Ubiquitin and Protein Degradation, Part B Ubiquitin and Protein Degradation, Part B will cover chemical biology, ubiquitin derivatives and ubiquitin-like proteins, deubiquitinating enzymes, proteomics as well as techniques to monitor protein degradation. The chapters are highly methodological and focus on application of techniques.*Second part of the Ubiquitin and Protein Degration series*Topics include: E1 Enzymes, E2 Enzymes, E3... |
 | Alzheimer: 100 Years and Beyond (Research and Perspectives in Alzheimer's Disease) Few medical or scientific addresses have so unmistakeably made history as the presentation delivered by Alois Alzheimer on November 4, 1906 in Tübingen. The celebratory event, ""Alzheimer 100 Years and Beyond"" organized on the initiation of the Alzheimer community in Germany and worldwide, in collaboration with the Fondation Ipsen, was the highlight of the Year of Alzheimer. However, beyond... |
 | Protein Degradation: The Ubiquitin-Proteasome System and Disease (Protein Degradation) This final volume in the series focuses on malfunctions of the ubiquitin-proteasome system and their role in human disease. The editors and authors represent unmatched expertise, comprising virtually all the top scientists in the field, including the pioneers of protein degradation research. From the contents: Ubiquitin and cancer Ubiquitin and liver cancer ... |
 | The Ubiquitin Proteasome System in the Central Nervous System: From Physiology to Pathology |
 | Ubiquitin-Proteasome Protocols (Methods in Molecular Biology) A collection of cutting-edge techniques for studying ubiquitin-dependent protein degradation via the proteasome. The topics covered range broadly from basic biochemistry to cellular assays to discovery techniques using mass spectrometric analysis. These biochemical and cellular methods are necessary to explore the ubiquitin-proteasome system and ubiquitin-proteasome-dependent functions.... |
| The Ubiquitin-proteasome System (Essays in Biochemistry) by J. Mayer, R. Layfield | |
 | Acute Promyelocytic Leukemia: Molecular Genetics, Mouse Models and Targeted Therapy (Current Topics in Microbiology and Immunology) Over the past 10 years, work on acute promyelocytic leukemia (APL) has become the paradigm of translational research that began with the discovery of a recurrent chromosomal translocation, followed by the identification of the genes and proteins involved, finding their molecular functions in transcriptional control, establishing mouse models and culminating in the development of targeted... |
| The heterodimeric elongin BC complex by Christopher Scott Brower | |
 | Ubiquitin |
| Ubiquitin And Protein Degradation, Part A (methods In Enzymology) (methods In Enzymology) by Sidney P. Colowick, Melvin I. Simon Raymond J. Deshaies |
| © 2008 BrightSurf.com |