Abstract:
:The functional receptor for insect ecdysteroid hormones is a heterodimer consisting of two nuclear hormone receptors, ecdysteroid receptor (EcR) and the retinoid X receptor homologue Ultraspiracle (USP). Although ecdysone is commonly thought to be a hormone precursor and 20-hydroxyecdysone (20E), the physiologically active steroid, little is known about the relative activity of ecdysteroids in various arthropods. As a step toward characterization of potential differential ligand recognition, we have analyzed the activities of various ecdysteroids using gel mobility shift assays and transfection assays in Schneider-2 (S2) cells. Ecdysone showed little activation of the Drosophila melanogaster receptor complex (DmEcR-USP). In contrast, this steroid functioned as a potent ligand for the mosquito Aedes aegypti receptor complex (AaEcR-USP), significantly enhancing DNA binding and transactivating a reporter gene in S2 cells. The mosquito receptor also displayed higher hormone-independent DNA binding activity than the Drosophila receptor. Subunit-swapping experiments indicated that the EcR protein, not the USP protein, was responsible for ligand specificity. Using domain-swapping techniques, we made a series of Aedes and Drosophila EcR chimeric constructs. Differential ligand responsiveness was mapped near the C terminus of the ligand binding domain, within the identity box previously implicated in the dimerization specificity of nuclear receptors. This region includes helices 9 and 10, as determined by comparison with available crystal structures obtained from other nuclear receptors. Site-directed mutagenesis revealed that Phe529 in Aedes EcR, corresponding to Tyr611 in Drosophila EcR, was most critical for ligand specificity and hormone-independent DNA binding activity. These results demonstrated that ecdysone could function as a bona fide ligand in a species-specific manner.
journal_name
Mol Cell Bioljournal_title
Molecular and cellular biologyauthors
Wang SF,Ayer S,Segraves WA,Williams DR,Raikhel ASdoi
10.1128/mcb.20.11.3870-3879.2000subject
Has Abstractpub_date
2000-06-01 00:00:00pages
3870-9issue
11eissn
0270-7306issn
1098-5549journal_volume
20pub_type
杂志文章abstract::Epidermal growth factor (EGF) induces tyrosine phosphorylation of the Shc adapter protein, which plays an important role in EGF-stimulated mitogenesis. Shc stimulates Ras/mitogen-activated protein kinase (MAPK) through forming a complex with Grb2 at the phosphorylated tyrosine (Y) residue 317. In this study, we identi...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.17.4.1824
更新日期:1997-04-01 00:00:00
abstract::We analyzed sites of macronuclear telomere addition at a single genetic locus in Paramecium tetraurelia. We showed that in homozygous wild-type cells, differential genomic processing during macronuclear development resulted in the A surface antigen gene being located 8, 13, or 26 kilobases upstream from a macronuclear...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.8.1.251
更新日期:1988-01-01 00:00:00
abstract::The CBP/p300 family of proteins comprises related acetyltransferases that coactivate signal-responsive transcription. Recent evidence suggests that p300/CBP may also interact directly with complexes that mediate different aspects of DNA metabolism such as replication and repair. In this report, we show that loss of dC...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.01283-06
更新日期:2007-01-01 00:00:00
abstract::A previously uncharacterized Saccharomyces cerevisiae gene, FAL1, was found by sequence comparison as a homolog of the eukaryotic translation initiation factor 4A (eIF4A). Fal1p has 55% identity and 73% similarity on the amino acid level to yeast eIF4A, the prototype of ATP-dependent RNA helicases of the DEAD-box prot...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.17.12.7283
更新日期:1997-12-01 00:00:00
abstract::The gastrointestinal glutathione peroxidase (GI-GPx, GPx2) is a selenoprotein that was suggested to act as barrier against hydroperoxide absorption but has also been implicated in the control of inflammation and malignant growth. In CaCo-2 cells, GI-GPx was induced by t-butyl hydroquinone (tBHQ) and sulforaphane (SFN)...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.25.12.4914-4923.2005
更新日期:2005-06-01 00:00:00
abstract::In heat-shocked tomato cell cultures, cytoplasmic heat shock granules (HSGs) are tightly associated with a specific subset of mRNAs coding mainly for the untranslated control proteins. This messenger ribonucleoprotein complex was banded in a CsCl gradient after fixation with formaldehyde (approximately 1.30 g/cm3). It...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.9.3.1298
更新日期:1989-03-01 00:00:00
abstract::Box C/D snoRNPs, factors essential for ribosome biogenesis, are proposed to be assembled in the nucleoplasm before localizing to the nucleolus. However, recent work demonstrated the involvement of nuclear export factors in this process, suggesting that export may take place. Here we show that there are distinct distri...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.00516-07
更新日期:2007-10-01 00:00:00
abstract::The receptors for thyroid hormone (T3R), all-trans-retinoic acid (RAR), and 9-cis-retinoic acid (RXR) bind DNA response elements as homo- and heterodimers. The ligand-binding domains of these receptors contain nine conserved heptads proposed to play a role in dimerization. Mutant receptors with changes in the first or...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.13.9.5725
更新日期:1993-09-01 00:00:00
abstract::We have been interested in how Rous sarcoma virus (RSV) influences transformed cell morphology and compared the molecular properties of chicken embryo cells (CEC) infected with mutants of RSV that induce the fusiform transformed cell morphology with those of CEC infected by wild-type RSV, which induces the more normal...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.5.11.3097
更新日期:1985-11-01 00:00:00
abstract::We demonstrate that ATF3, a member of the ATF/CREB family of transcription factors, is induced in a variety of stressed tissues: mechanically injured liver, toxin-injured liver, blood-deprived heart, and postseizure brain. We also demonstrate that an ATF3-interacting protein, gadd153/Chop10, forms a nonfunctional hete...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.16.3.1157
更新日期:1996-03-01 00:00:00
abstract::Two Drosophila tumor necrosis factor receptor-associated factors (TRAF), DTRAF1 and DTRAF2, are proposed to have similar functions with their mammalian counterparts as a signal mediator of cell surface receptors. However, their in vivo functions and related signaling pathways are not fully understood yet. Here, we sho...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.23.22.7982-7991.2003
更新日期:2003-11-01 00:00:00
abstract::In Saccharomyces cerevisiae, many amino acid biosynthetic pathways are coregulated by a complex general control system: starvation for a single amino acid results in the derepression of amino acid biosynthetic genes in multiple pathways. Derepression of these genes is mediated by positive (GCN) and negative (GCD) regu...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.6.9.3150
更新日期:1986-09-01 00:00:00
abstract::For proper male sexual differentiation, anti-Müllerian hormone (AMH) must be tightly regulated during embryonic development to promote regression of the Müllerian duct. However, the molecular mechanisms specifying the onset of AMH in male mammals are not yet clearly defined. A DNA-binding element for the steroidogenic...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.18.11.6653
更新日期:1998-11-01 00:00:00
abstract::Essential for embryonic development, the polycomb group protein enhancer of zeste homolog 2 (EZH2) is overexpressed in breast and prostate cancers and is implicated in the growth and aggression of the tumors. The tumorigenic mechanism underlying EZH2 overexpression is largely unknown. It is believed that EZH2 exerts i...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.00162-07
更新日期:2007-07-01 00:00:00
abstract::The silent mating-type loci of Saccharomyces cerevisiae, HML and HMR, are flanked by transcriptional silencers that have ARS activity (i.e., they function as replication origins when in plasmids). To test whether these ARS elements are chromosomal origins, we mapped origins near HML (close to the left telomere of chro...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.11.10.5346
更新日期:1991-10-01 00:00:00
abstract::Latent Epstein-Barr virus (EBV) is maintained as a nucleosome-covered episome that can be transcriptionally activated by overexpression of the viral immediate-early protein, Zta. We show here that reactivation of latent EBV by Zta can be significantly enhanced by coexpression of the cellular coactivators CREB binding ...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.19.3.1617
更新日期:1999-03-01 00:00:00
abstract::The influence of transcription on homologous intrachromosomal recombination between direct and inverted repeats has been examined by using Chinese hamster ovary cells. Recombination was monitored between two integrated neomycin (neo) genes, including one silent allele and a second allele regulated by the inducible mou...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.12.12.5311
更新日期:1992-12-01 00:00:00
abstract::The immunoglobulin M heavy-chain locus contains two poly(A) sites which are alternatively expressed during B-cell differentiation. Despite its promoter proximal location, the secretory poly(A) site is not expressed in undifferentiated cells. Crucial to the activation of the secretory poly(A) site during B-cell differe...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.24.14.6162-6171.2004
更新日期:2004-07-01 00:00:00
abstract::Translocation of preproteins across the mitochondrial outer membrane is mediated by the TOM complex. This complex consists of receptor components for the initial contact with preproteins at the mitochondrial surface and membrane-embedded proteins which promote transport and form the translocation pore. In order to und...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.18.9.5256
更新日期:1998-09-01 00:00:00
abstract::p105 (NFKB1) acts in a dual way as a cytoplasmic IkappaB molecule and as the source of the NF-kappaB p50 subunit upon processing. p105 can form various heterodimers with other NF-kappaB subunits, including its own processing product, p50, and these complexes are signal responsive. Signaling through the IkappaB kinase ...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.21.4.1024-1035.2001
更新日期:2001-02-01 00:00:00
abstract::Strains of the yeast Saccharomyces cerevisiae defective in transcription factor UAF give rise to variants able to grow by transcribing endogenous ribosomal DNA (rDNA) by RNA polymerase II (Pol II). We have demonstrated that the switch to growth using the Pol II system consists of two steps: a mutational alteration in ...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.19.12.8559
更新日期:1999-12-01 00:00:00
abstract::The numerous members of the steroid/nuclear hormone receptor superfamily act as direct transducers of circulating signals, such as steroids, thyroid hormone, and vitamin or lipid metabolites, and modulate the transcription of specific target genes, primarily as dimeric complexes. The receptors for 9-cis retinoic acid ...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.17.4.1923
更新日期:1997-04-01 00:00:00
abstract::c-sis/platelet-derived growth factor 2 (PDGF-2) is a prototype growth factor with transforming potential. The c-sis/PDGF-2 transcript contains a long 5' untranslated sequence (UTS) that is highly G.C rich. To examine the influence of this sequence on sis/PDGF-2 expression, we localized the c-sis/PDGF-2 promoter and us...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.8.1.284
更新日期:1988-01-01 00:00:00
abstract::Using an in vitro binding-site selection assay, we have demonstrated that c-Myc-Max complexes bind not only to canonical CACGTG or CATGTG motifs that are flanked by variable sequences but also to noncanonical sites that consist of an internal CG or TG dinucleotide in the context of particular variations in the CA--TG ...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.13.9.5216
更新日期:1993-09-01 00:00:00
abstract::The hemagglutinin-neuraminidase (HN) protein of paramyxoviruses is likely in the unusual class of glycoproteins with the amino terminus cytoplasmic and the carboxy terminus lumenal or external to the cell. The properties of the membrane insertion of the HN protein of Newcastle disease virus, a prototype paramyxovirus,...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.7.4.1386
更新日期:1987-04-01 00:00:00
abstract::COUP-TF, an orphan member of the nuclear receptor superfamily, has been proposed to play a key role in regulating organogenesis, neurogenesis, and cellular differentiation during embryonic development. Since heterodimierization is a common theme within the nuclear receptor superfamily and has been demonstrated to modu...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.16.5.2332
更新日期:1996-05-01 00:00:00
abstract::The initiation of adenovirus DNA takes place at the termini of the viral genome and requires the presence of specific nucleotide sequence elements. To define the sequence organization of the viral origin, we tested a large number of deletion, insertion, and base substitution mutants for their ability to support initia...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.7.2.864
更新日期:1987-02-01 00:00:00
abstract::Changes in endothelial nitric oxide synthase (eNOS) expression may be involved in the endothelium-dependent vasorelaxation dysfunction associated with several vascular diseases. In the present work, we demonstrate that eNOS mRNA contains a previously undescribed cis element in the 3' untranslated region (3' UTR). A U+...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.17.10.5719
更新日期:1997-10-01 00:00:00
abstract::Genomic instability, including the ability to undergo gene amplification, is a hallmark of neoplastic cells. Similar to normal cells, "nonpermissive" REF52 cells do not develop resistance to N-(phosphonacetyl)-L-aspartate (PALA), an inhibitor of the synthesis of pyrimidine nucleotides, through amplification of cad, th...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.18.1.536
更新日期:1998-01-01 00:00:00
abstract::We report a negative feedback loop between the signaling protein phospholipase D (PLD), phosphatidic acid (PA), and a specific set of microRNAs (miRNAs) during nutrient starvation of breast cancer cells. We show that PLD expression is increased in four breast cancer cell lines and that hypoxia, cell overcrowding, and ...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.00711-15
更新日期:2016-01-19 00:00:00