'Human lysyl-tRNA synthetase (LysRS) is a tRNA-binding protein that is selectively packaged into HIV-1 along with its cognate tRNALys isoacceptors. Evidence exists that Gag alone is sufficient for the incorporation of LysRS into virions. Herein, using both in vitro and in vivo methods, we begin to map regions in Gag ... More
The anti-trp RNA-binding attenuation protein (Anti-TRAP), AT, recognizes the tryptophan-activated RNA binding domain of the TRAP regulatory protein.
'In Bacillus subtilis, the trp RNA-binding attenuation protein (TRAP) regulates expression of genes involved in tryptophan metabolism in response to the accumulation of l-tryptophan. Tryptophan-activated TRAP negatively regulates expression by binding to specific mRNA sequences and either promoting transcription termination or blocking translation initiation. Conversely, the accumulation of uncharged tRNA(Trp) ... More
The ISG15 isopeptidase UBP43 is regulated by proteolysis via the SCFSkp2 ubiquitin ligase.
AuthorsTokarz S, Berset C, La Rue J, Friedman K, Nakayama K, Nakayama K, Zhang DE, Lanker S,
JournalJ Biol Chem
PubMed ID15342634
'The Skp2 oncoprotein belongs to the family of F-box proteins that function as substrate recognition factors for SCF (Skp1, cullin, F-box protein) E3 ubiquitin-ligase complexes. Binding of the substrate to the SCFSkp2 complex catalyzes the conjugation of ubiquitin molecules to the bound substrate, resulting in multi-ubiquitination and rapid degradation by ... More
A proteolytic transmembrane signaling pathway and resistance to beta-lactams in staphylococci.
AuthorsZhang HZ, Hackbarth CJ, Chansky KM, Chambers HF.
JournalScience
PubMed ID11239156
beta-Lactamase and penicillin-binding protein 2a mediate staphylococcal resistance to beta-lactam antibiotics, which are otherwise highly clinically effective. Production of these inducible proteins is regulated by a signal-transducing integral membrane protein and a transcriptional repressor. The signal transducer is a fusion protein with penicillin-binding and zinc metalloprotease domains. The signal for ... More
The solution structure and interactions of CheW from Thermotoga maritima.
Authors Griswold Ian J; Zhou Hongjun; Matison Mikenzie; Swanson Ronald V; McIntosh Lawrence P; Simon Melvin I; Dahlquist Frederick W;
JournalNat Struct Biol
PubMed ID11799399
Using protein from the hyperthermophile Thermotoga maritima, we have determined the solution structure of CheW, an essential component in the formation of the bacterial chemotaxis signaling complex. The overall fold is similar to the regulatory domain of the chemotaxis kinase CheA. In addition, interactions of CheW with CheA were monitored ... More
A thiol peroxidase is an H2O2 receptor and redox-transducer in gene activation.
The Yap1 transcription factor regulates hydroperoxide homeostasis in S. cerevisiae. Yap1 is activated by oxidation when hydroperoxide levels increase. We show that Yap1 is not directly oxidized by hydroperoxide. We identified the glutathione peroxidase (GPx)-like enzyme Gpx3 as a second component of the pathway, serving the role of sensor and ... More
Characterization of the NR1, NR2A, and NR2C receptor proteins.
AuthorsKopke AK, Bonk I, Sydow S, Menke H, Spiess J
JournalProtein Sci
PubMed ID8298456
N-Methyl-D-aspartate (NMDA) receptor subunits were characterized with seven polyclonal antibodies. The antibodies were directed against NR1- A, NR2A-N1, and NR2C-N1, representing N-terminal sequences of the NR1, NR2A, and NR2C subunits, and against NR1-E, NR2A-C1, and NR2C-C1, derived from C-terminal sequences of these subunits. The anti-NR1-D antibody was raised against the ... More
The chloroplast protein import receptors Toc34 and Toc159 are phosphorylated by distinct protein kinases.
Authors Fulgosi Hrvoje; Soll Jurgen;
JournalJ Biol Chem
PubMed ID11773075
The molecular composition of chloroplast outer and inner envelope translocons is fairly well established, but little is known about mechanisms and elements involved in import regulation. After synthesis in the cytosol, chloroplast targeted precursor proteins are recognized by outer envelope receptors Toc34 and Toc159. Phosphorylation plays an important role in ... More
Dual targeting of spinach protoporphyrinogen oxidase II to mitochondria and chloroplasts by alternative use of two in-frame initiation codons.
Authors Watanabe N; Che F S; Iwano M; Takayama S; Yoshida S; Isogai A;
JournalJ Biol Chem
PubMed ID11274159
Protoporphyrinogen oxidase (Protox) is the final enzyme in the common pathway of chlorophyll and heme biosynthesis. Two Protox isoenzymes have been described in tobacco, a plastidic and a mitochondrial form. We isolated and sequenced spinach Protox cDNA, which encodes a homolog of tobacco mitochondrial Protox (Protox II). Alignment of the ... More
Evidence for a direct interaction between the tumor suppressor serpin, maspin, and types I and III collagen.
Authors Blacque Oliver E; Worrall D Margaret;
JournalJ Biol Chem
PubMed ID11788595
Maspin (mammary serine protease inhibitor) was originally identified as a tumor suppressor protein in human breast epithelial cells and is a member of the serine proteases inhibitor (serpin) superfamily. It inhibits tumor cell motility and angiogenesis, and although predominantly cytoplasmic, it is also localized to the cell surface. In this ... More
The N-terminal coiled coil domain of the cytohesin/ARNO family of guanine nucleotide exchange factors interacts with the scaffolding protein CASP.
Authors Mansour Marc; Lee Stella Y; Pohajdak Bill;
JournalJ Biol Chem
PubMed ID12052827
Cytohesin is a guanine nucleotide exchange factor that regulates members of the ADP-ribosylation factor (ARF) family of small GTPases. All of the members of the cytohesin family (including ARNO, ARNO3, and the newly characterized cytohesin-4) have a similar domain distribution consisting of a Sec7 homology domain, a pleckstrin homology domain, ... More
The mechanism for regulation of the F-actin binding activity of IQGAP1 by calcium/calmodulin.
Authors Mateer Scott C; McDaniel Amanda E; Nicolas Valerie; Habermacher Geoffrey M; Lin Mei-Jung Sun; Cromer Damond A; King Michelle E; Bloom George S;
JournalJ Biol Chem
PubMed ID11809768
IQGAP1 colocalizes with actin filaments in the cell cortex and binds in vitro to F-actin and several signaling proteins, including calmodulin, Cdc42, Rac1, and beta-catenin. It is thought that the F-actin binding activity of IQGAP1 is regulated by its reversible association with these signaling molecules, but the mechanisms have remained ... More