Mouse protein 25 alpha (MO25 alpha) is a 40-kDa protein that, together with the STE20-related adaptor-alpha (STRAD alpha) pseudo kinase, forms a regulatory complex capable of stimulating the activity of the LKB1 tumor suppressor protein kinase. The latter is mutated in the inherited Peutz-Jeghers cancer syndrome (PJS). MO25 alpha binds directly to a conserved Trp-Glu-Phe sequence at the STRAD alpha C terminus, markedly enhancing binding of STRAD alpha to LKB1 and increasing LKB1 catalytic activity. The MO25 alpha crystal structure reveals a helical repeat fold, distantly related to the Armadillo proteins. A complex with the STRAD alpha peptide reveals a hydrophobic pocket that is involved in a unique and specific interaction with the Trp-Glu-Phe motif, further supported by mutagenesis studies. The data represent a first step toward structural analysis of the LKB1-STRAD-MO25 complex, and suggests that MO25 alpha is a scaffold protein to which other regions of STRAD-LKB1, cellular LKB1 substrates or regulatory components could bind.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1038/nsmb716 | DOI Listing |
Microglia-mediated neuroinflammation plays a dual role in various brain diseases due to distinct microglial phenotypes, including deleterious M1 and neuroprotective M2. There is growing evidence that the peroxisome proliferator-activated receptor γ (PPARγ) agonist rosiglitazone prevents lipopolysaccharide (LPS)-induced microglial activation. Here, we observed that antagonizing PPARγ promoted LPS-stimulated changes in polarization from the M1 to the M2 phenotype in primary microglia.
View Article and Find Full Text PDFInt J Biochem Cell Biol
July 2015
The Catholic University Liver Research Center & WHO Collaborating Center of Viral Hepatitis, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea; Department of Internal Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea. Electronic address:
Mechanisms associated with the progression of non-alcoholic fatty liver disease (NAFLD) remain unclear. We attempted to identify the pattern of altered gene expression at different time points in a high fat diet (HFD)-induced NAFLD mouse model. The early up-regulated genes are mainly involved in the innate immune responses, while the late up-regulated genes represent the inflammation processes.
View Article and Find Full Text PDFBiochem J
August 2013
School of Biological Sciences, University of Reading, Whiteknights Campus, Harborne Building, Reading RG6 6AS, U.K.
The GCKIII (germinal centre kinase III) subfamily of the mammalian Ste20 (sterile 20)-like group of serine/threonine protein kinases comprises SOK1 (Ste20-like/oxidant-stress-response kinase 1), MST3 (mammalian Ste20-like kinase 3) and MST4. Initially, GCKIIIs were considered in the contexts of the regulation of mitogen-activated protein kinase cascades and apoptosis. More recently, their participation in multiprotein heterocomplexes has become apparent.
View Article and Find Full Text PDFMol Cell
March 2010
Dardinger Laboratory for Neuro-oncology and Neurosciences, Department of Neurological Surgery, The Ohio State University Medical Center and James Comprehensive Cancer Center, Columbus, OH 43210, USA.
To sustain tumor growth, cancer cells must be able to adapt to fluctuations in energy availability. We have identified a single microRNA that controls glioma cell proliferation, migration, and responsiveness to glucose deprivation. Abundant glucose allows relatively high miR-451 expression, promoting cell growth.
View Article and Find Full Text PDFBiochem Pharmacol
November 2008
Department of Human Nutrition and Metabolism, Hebrew University Medical School, Ein Kerem, Jerusalem 91120, Israel.
The antidiabetic efficacy of first-line insulin sensitizers (e.g., metformin, glitazones) is accounted for by activation of AMP-activated protein kinase (AMPK).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!