A dynamic switch between inhibitory and excitatory currents in a neuronal glutamate transporter.
AuthorsMelzer N, Torres-Salazar D, Fahlke C,
JournalProc Natl Acad Sci U S A
PubMed ID16365297
'Excitatory amino acid transporters (EAATs) terminate glutamatergic synaptic transmission and maintain extracellular glutamate concentrations in the central nervous system below excitotoxic levels. In addition to sustaining a secondary-active glutamate transport, EAAT glutamate transporters also function as anion-selective channels. Here, we report a gating process that makes anion channels associated with ... More
Long term association of the cytokine receptor gp130 and the Janus kinase Jak1 revealed by FRAP analysis.
AuthorsGiese B, Au-Yeung CK, Herrmann A, Diefenbach S, Haan C, Küster A, Wortmann SB, Roderburg C, Heinrich PC, Behrmann I, Müller-Newen G,
JournalJ Biol Chem
PubMed ID12878601
'Signal transduction through cytokine receptors is mediated mainly by non-covalently associated Jak tyrosine kinases. By confocal microscopy, the cytokine receptor gp130 and Jak1, fused with either yellow (YFP) or cyan (CFP) fluorescent protein, were found to be colocalized predominantly at intracellular vesicular structures and at the plasma membrane. Quantitative fluorescence ... More
Pattern of genes influenced by conditional expression of the transcription factors HNF6, HNF4alpha and HNF1beta in a pancreatic beta-cell line.
'Using the rat insulinoma cell line INS-1 we generated beta-cell clones that are most efficient for gene transfer, as they contain an FRT site for Flp recombinase-mediated, site-directed integration of a single copy transgene. Therefore, the gene-of-interest can be introduced by DNA transfection without the need to select individual cell ... More
Folliculin encoded by the BHD gene interacts with a binding protein, FNIP1, and AMPK, and is involved in AMPK and mTOR signaling.
AuthorsBaba M, Hong SB, Sharma N, Warren MB, Nickerson ML, Iwamatsu A, Esposito D, Gillette WK, Hopkins RF, Hartley JL, Furihata M, Oishi S, Zhen W, Burke TR, Linehan WM, Schmidt LS, Zbar B,
JournalProc Natl Acad Sci U S A
PubMed ID17028174
'Birt-Hogg-Dubé syndrome, a hamartoma disorder characterized by benign tumors of the hair follicle, lung cysts, and renal neoplasia, is caused by germ-line mutations in the BHD(FLCN) gene, which encodes a tumor-suppressor protein, folliculin (FLCN), with unknown function. The tumor-suppressor proteins encoded by genes responsible for several other hamartoma syndromes, LKB1, ... More
Discovery of the ergothioneine transporter.
AuthorsGründemann D, Harlfinger S, Golz S, Geerts A, Lazar A, Berkels R, Jung N, Rubbert A, Schömig E,
JournalProc Natl Acad Sci U S A
PubMed ID15795384
'Variants of the SLC22A4 gene are associated with susceptibility to rheumatoid arthritis and Crohn''s disease. SLC22A4 codes for an integral membrane protein, OCTN1, that has been presumed to carry organic cations like tetraethylammonium across the plasma membrane. Here, we show that the key substrate of this transporter is in fact ... More
Trpm7 regulates cell adhesion by controlling the calcium dependent protease calpain.
AuthorsSu LT, Agapito MA, Li M, T N Simonson W, Huttenlocher A, Habas R, Yue L, Runnels LW,
JournalJ Biol Chem
PubMed ID16436382
'M-calpain is a protease implicated in the control of cell adhesion through focal adhesion disassembly. The mechanism by which the enzyme is spatially and temporally controlled is not well understood, particularly because calpain''s dependence on calcium exceeds the sub-micromolar concentrations normally observed in cells. Here we show that the channel-kinase ... More
Human immunodeficiency virus type 1 Vpr-dependent cell cycle arrest through a mitogen-activated protein kinase signal transduction pathway.
AuthorsYoshizuka N, Yoshizuka-Chadani Y, Krishnan V, Zeichner SL,
JournalJ Virol
PubMed ID16103188
The human immunodeficiency virus type 1 (HIV-1) Vpr protein has important functions in advancing HIV pathogenesis via several effects on the host cell. Vpr mediates nuclear import of the preintegration complex, induces host cell apoptosis, and inhibits cell cycle progression at G(2), which increases HIV gene expression. Some of Vpr's ... More
AuthorsXia ZB, Popovic R, Chen J, Theisler C, Stuart T, Santillan DA, Erfurth F, Diaz MO, Zeleznik-Le NJ,
JournalProc Natl Acad Sci U S A
PubMed ID16169901
MLL, involved in many chromosomal translocations associated with acute myeloid and lymphoid leukemia, has >50 known partner genes with which it is able to form in-frame fusions. Characterizing important downstream target genes of MLL and of MLL fusion proteins may provide rational therapeutic strategies for the treatment of MLL-associated leukemia. ... More
Fibroblast growth factor receptor 1 is a key regulator of early adipogenic events in human preadipocytes.
Cell number is an important determinant of adipose tissue mass, and the coordinated proliferation and differentiation of preadipocytes into mature lipid-laden adipocytes underpins the increased adipose tissue mass associated with obesity. Despite this, the molecular cues governing such adipose tissue expansion are poorly understood. We previously reported that fibroblast growth ... More
Overexpression of the protein phosphatase 2A regulatory subunit Bgamma promotes neuronal differentiation by activating the MAP kinase (MAPK) cascade.
Authors Strack Stefan;
JournalJ Biol Chem
PubMed ID12191994
Protein serine/threonine phosphatase 2A (PP2A) is a multifunctional regulator of cellular signaling. Variable regulatory subunits associate with a core dimer of scaffolding and catalytic subunits and are postulated to dictate substrate specificity and subcellular location of the heterotrimeric PP2A holoenzyme. The role of brain-specific regulatory subunits in neuronal differentiation and ... More