DOCSLIB.ORG

The F-Box Subunit of the SCF E3 Complex Is Encoded by a Diverse Superfamily of Genes in Arabidopsis

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The F-Box Subunit of the SCF E3 Complex Is Encoded by a Diverse Superfamily of Genes in Arabidopsis The F-box subunit of the SCF E3 complex is encoded by a diverse superfamily of genes in Arabidopsis Jennifer M. Gagne*, Brian P. Downes*, Shin-Han Shiu*†, Adam M. Durski*, and Richard D. Vierstra*‡ *Cellular and Molecular Biology Program and the Department of Horticulture, 1575 Linden Drive, University of Wisconsin, Madison, WI 53706; and †MIPS͞Institute for Bioinformatics, GSF-National Research Center for Environment and Health, 85764 Neuherberg, Germany Communicated by Eldon H. Newcomb, University of Wisconsin, Madison, WI, June 6, 2002 (received for review April 23, 2002) The covalent attachment of ubiquitin is an important determinant chain of Ubs is attached, typically using lysine-48 within the Ub for selective protein degradation by the 26S proteasome in plants moieties as the acceptor site for polymerization. and animals. The specificity of ubiquitination is often controlled by Currently, five types of E3s have been identified that differ ubiquitin-protein ligases (or E3s), which facilitate the transfer of according to their subunit organization and͞or mechanism of Ub ubiquitin to appropriate targets. One ligase type, the SCF E3s are transfer (1, 3, 4). One important E3 type is the SCF complex, composed of four proteins, cullin1͞Cdc53, Rbx1͞Roc1͞Hrt1, Skp1, which in yeast (Saccharomyces cerevisiae) is composed of four and an F-box protein. The F-box protein, which identifies the primary subunits—cullin1͞Cdc53, Rbx1͞Roc1͞Hrt1, Skp1, and targets, binds to the Skp1 component of the complex through a an F-box protein (3, 4). The cullin1, Rbx1, and Skp1 subunits degenerate N-terminal Ϸ60-aa motif called the F-box. Using pub- appear to form the core ligase activity, with Rbx1 recruiting the lished F-boxes as queries, we have identified 694 potential F-box E2 bearing an activated Ub. F-box proteins perform the crucial genes in Arabidopsis, making this gene superfamily one of the role of delivering appropriate targets to the complex. These largest currently known in plants. Most of the encoded proteins proteins all contain a degenerate Ϸ60-aa N-terminal motif called contain interaction domains C-terminal to the F-box that presum- the F-box, which is used to interact with the rest of the SCF ably participate in substrate recognition. The F-box proteins can be complex by binding to the Skp subunit. The C-terminal portions classified via a phylogenetic approach into five major families, of F-box proteins typically contain a variable protein-interaction which can be further organized into multiple subfamilies. Se- domain that binds the target and thus confers specificity to the quence diversity within the subfamilies suggests that many F-box SCF complex. In yeast and animals, a number of F-box proteins proteins have distinct functions and͞or substrates. Representa- are present, easily classified by the nature of this interaction tives of all of the major families interact in yeast two-hybrid domain (3, 4). In yeast, for example, the F-box protein Grr1p experiments with members of the Arabidopsis Skp family support- contains C-terminal leucine-rich repeats (LRRs) that recruit the ing their classification as F-box proteins. For some, a limited phosphorylated forms of the cyclins Cln1p and Cln2p to the preference for Skps was observed, suggesting that a hierarchical SCFGrr1 complex, whereas the Cdc4 F-box protein contains organization of SCF complexes exists defined by distinct Skp͞F-box WD-40 repeats that recruit the phosphorylated form of the protein pairs. Collectively, the data shows that Arabidopsis has cyclin-dependent kinase inhibitor Sic1 to the SCFcdc4 complex. exploited the SCF complex and the ubiquitin͞26S proteasome The existence of multiple F-box proteins, each with unique pathway as a major route for cellular regulation and that a diverse specificity or specificities would allow SCFs to ubiquitinate a array of SCF targets is likely present in plants. diverse array of substrates. Recent studies in Arabidopsis thaliana indicate that F-box rotein degradation is an important posttranscriptional reg- proteins and SCF complexes play critical roles in various aspects ulatory process that allows cells to respond rapidly to intra- of plant growth and development (2). ASK1, one of the 19 Skp P proteins in Arabidopsis (5), is involved in male gametogenesis cellular signals and changing environmental conditions by ad- and floral organ identity (6, 7). Arabidopsis F-box (FBX) genes justing the levels of key proteins. One major proteolytic route in have been implicated in auxin (TIR1) and jasmonate signaling eukaryotes involves the ubiquitin (Ub)͞26S proteasome pathway (COI1) (8, 9), floral homeosis (UFO) (10), flowering time and (1, 2). Here, proteins destined for degradation become modified circadian clocks (ZTL͞FKF͞LKP2) (11–13), leaf senescence and by the covalent attachment of multiple Ubs. The ubiquitinated lateral shoot branching (ORE1͞MAX2) (14, 15), and photomor- substrates are then recognized by the 26S proteasome and phogenesis (EID1) (16). Cursory searches of the Arabidopsis degraded while the Ub moieties are recycled. In both yeast and genome detected many other FBX loci, suggesting that they animals, the Ub͞26S proteasome pathway is responsible for comprise a large gene family (17, 18). For example, Andrade et removing most abnormal polypeptides and many short-lived cell al. (19) identified 48 genes encoding proteins with Kelch repeats regulators, which in turn control numerous processes, including following a degenerate F-box motif. To further determine the the cell cycle, signal transduction, transcription, stress responses, complexity of the F-box protein family in plants, we conducted and defense (1). Recent studies infer similar roles for the an exhaustive search for FBX-related loci in the Arabidopsis pathway in plants. For example, mutations in specific compo- ͞ genome. This search identified 694 potential FBX genes, making nents of the Arabidopsis Ub 26S proteasome pathway block this superfamily one of the largest found so far in plants. The size embryogenesis, hormonal responses, floral homeosis, photo- and diversity of this collection suggest that SCF E3s impact most morphogenesis, circadian rhythms, senescence, and pathogen aspects of plant cell biology presumably by recognizing and invasion (2). Although many of the components of this pathway ubiquitinating a wide array of protein targets. have been described, the mechanisms for target recognition remain poorly defined. Materials and Methods Ub conjugation is achieved through an ATP-dependent reac- Prediction of F-Box Proteins. All F-box proteins published as of tion cascade involving the sequential action of three enzymes, 01͞17͞01 were used as queries in multiple BLAST searches (20) E1, E2s, and E3s (1). As the final enzyme in the cascade, the E3s or Ub-protein ligases are responsible for recognizing the sub- strate and facilitating Ub transfer, which results in the formation Abbreviations: AGI, Arabidopsis Genome Initiative; LRR, leucine-rich repeat; Ub, ubiquitin; of an isopeptide bond between a lysl ␧-amino group of the target Y2H, yeast two-hybrid. PLANT BIOLOGY and the C-terminal glycine carboxyl group of the Ub. Often a ‡To whom reprint requests should be addressed. E-mail: [email protected]. www.pnas.org͞cgi͞doi͞10.1073͞pnas.162339999 PNAS ͉ August 20, 2002 ͉ vol. 99 ͉ no. 17 ͉ 11519–11524 Downloaded by guest on September 24, 2021 against the Arabidopsis genome (annotated 01͞17͞2001). Se- quences predicted to encode F-boxes by the SMART and PFAM databases (http:͞͞smart.embl-heidelberg.de) were then used in BLAST searches against the complete, nonredundant, re- annotated Arabidopsis genome (released 02͞17͞01). One set of BLAST searches used only the F-box motifs and had an E value cutoff of 10, whereas the other set used the full-length proteins with a cutoff of 1e-10. Of the 1,849 nonredundant sequences retrieved, 650 were annotated by SMART͞PFAM as containing an F-box motif. Fifteen of the 650 loci were re-annotated as two F-box genes and another locus as three. Hand analysis led to the identification of 27 additional loci. Four of those loci are missing in the current annotation and have been named using the Arabidopsis Genome Initiative (AGI) numbers of the genes that bracket the locus. The additional 44 genes and the revised annotations are described in Table 2, which is published as supporting information on the PNAS web site, www.pnas.org. Four genes (At1g51290, At5g02700, At3g28410, and At3g49030) appear to contain two F-boxes; in these cases, the domain with a better match to the consensus F-box motif was used. Alignments, Phylogenetic Analysis, and EST Identification. Intron͞ exon organizations were based on the Arabidopsis genome annotation, our re-annotation data, and analysis of ESTs. F-box sequences were retrieved and aligned using CLUSTALX PC V.1.81 (21). An unrooted phylogenetic tree of the alignment was created by MEGA V.2.1 (22), using the p-distance method with gaps treated by pairwise deletion and a 1,000 bootstrap replicate. Alignments and trees of selected groups were generated by CLUSTALX MAC V.1.6b (21). Percent identities and similarities were calculated using MACBOXSHADE V.2.11 (Institute of Animal Fig. 1. Phylogenetic tree of the F-box protein superfamily from Arabidopsis. Health, Pirbright, U.K.). Additional domains were predicted The 60-aa F-box motifs from the 694 potential F-box proteins were aligned by using SMART and PFAM databases, BLAST searches, and sequence CLUSTALX. The alignment then was used to generate an unrooted phylogenetic alignments. Chromosomal maps were generated using the tree with MEGA 2.1, using the p-distance method and a bootstrap value of 1,000. Genome Pixelizer Tcl͞Tk script [www.atgc.org͞GenomePixel- Individual members of the tree are color-coded by (A) the nature of the ͞ ͞ domain(s) C-terminal to the F-box or (B) the number of introns within the izer (released 02 15 2002)]. The predicted mRNA sequences respective genes.
Load more

Recommended publications
  • The Role of F-Box Proteins During Viral Infection
    Int. J. Mol. Sci. 2013, 14, 4030-4049; doi:10.3390/ijms14024030 OPEN ACCESS International Journal of Molecular Sciences ISSN 1422-0067 www.mdpi.com/journal/ijms Review The Role of F-Box Proteins during Viral Infection Régis Lopes Correa 1, Fernanda Prieto Bruckner 2, Renan de Souza Cascardo 1,2 and Poliane Alfenas-Zerbini 2,* 1 Department of Genetics, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-970, Brazil; E-Mails: [email protected] (R.L.C.); [email protected] (R.S.C.) 2 Department of Microbiology/BIOAGRO, Federal University of Viçosa, Viçosa, MG 36570-000, Brazil; E-Mail: [email protected] * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +55-31-3899-2955; Fax: +55-31-3899-2864. Received: 23 October 2012; in revised form: 14 December 2012 / Accepted: 17 January 2013 / Published: 18 February 2013 Abstract: The F-box domain is a protein structural motif of about 50 amino acids that mediates protein–protein interactions. The F-box protein is one of the four components of the SCF (SKp1, Cullin, F-box protein) complex, which mediates ubiquitination of proteins targeted for degradation by the proteasome, playing an essential role in many cellular processes. Several discoveries have been made on the use of the ubiquitin–proteasome system by viruses of several families to complete their infection cycle. On the other hand, F-box proteins can be used in the defense response by the host. This review describes the role of F-box proteins and the use of the ubiquitin–proteasome system in virus–host interactions.
    [Show full text]
  • The Steady-State Repertoire of Human SCF Ubiquitin Ligase Complexes Does Not Require Ongoing Nedd8 Conjugation*□S
    Research Author’s Choice © 2011 by The American Society for Biochemistry and Molecular Biology, Inc. This paper is available on line at http://www.mcponline.org The Steady-State Repertoire of Human SCF Ubiquitin Ligase Complexes Does Not Require Ongoing Nedd8 Conjugation*□S J. Eugene Lee‡, Michael J. Sweredoski§, Robert L. J. Graham§, Natalie J. Kolawa‡, Geoffrey T. Smith§, Sonja Hess§, and Raymond J. Deshaies‡¶ʈ The human genome encodes 69 different F-box proteins jugating enzyme (E2). E2 charged with ubiquitin collaborates (FBPs), each of which can potentially assemble with Skp1- with ubiquitin ligase (E3) to ubiquitylate the target substrate. Cul1-RING to serve as the substrate specificity subunit of Multiple ubiquitin transfers may occur in a successive man- an SCF ubiquitin ligase complex. SCF activity is switched ner, resulting in the processive formation of an ubiquitin chain on by conjugation of the ubiquitin-like protein Nedd8 to (3). The second step is the energy-dependent proteolysis of Cul1. Cycles of Nedd8 conjugation and deconjugation the ubiquitin chain-tagged protein by the 26S proteasome acting in conjunction with the Cul1-sequestering factor complex. Cand1 are thought to control dynamic cycles of SCF as- There are nearly 600 ubiquitin ligases encoded in the hu- sembly and disassembly, which would enable a dynamic equilibrium between the Cul1-RING catalytic core of SCF man genome, and up to 241 (over 40%) are potentially drawn 1 and the cellular repertoire of FBPs. To test this hypothe- from the cullin–ring ligase (CRL) family (K. Hofmann, personal sis, we determined the cellular composition of SCF com- communication).
    [Show full text]
  • Multiple Ser/Thr-Rich Degrons Mediate the Degradation of Ci/Gli by the Cul3-HIB/SPOP E3 Ubiquitin Ligase
    Multiple Ser/Thr-rich degrons mediate the degradation of Ci/Gli by the Cul3-HIB/SPOP E3 ubiquitin ligase Qing Zhanga,1,2, Qing Shia,1, Yongbin Chena,1, Tao Yuea, Shuang Lia, Bing Wanga, and Jin Jianga,b,3 Departments of aDevelopmental Biology and bPharmacology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390 Communicated by Gary Struhl, Columbia University College of Physicians and Surgeons, New York, NY, October 19, 2009 (received for review September 8, 2009) The Cul3-based E3 ubiquitin ligases regulate many cellular pro- morphogenetic furrow (MF), where HIB acts together with Cul3 cesses using a large family of BTB domain–containing proteins as to degrade Ci, thereby limiting the duration of Hh signaling (11, their target recognition components, but how they recognize 12, 14). The Cul3-HIB regulatory circuit appears to be con- targets remains unknown. Here we identify and characterize served, because Gli proteins such as Gli2 and Gli3 can be degrons that mediate the degradation of the Hedgehog pathway degraded by HIB when expressed in Drosophila, and the mam- transcription factor cubitus interruptus (Ci)/Gli by Cul3-Hedghog– malian homolog of HIB, SPOP, can functionally replace HIB in induced MATH and BTB domain–containing protein (HIB)/SPOP. Ci degrading Ci (11). uses multiple Ser/Thr (S/T)-rich motifs that bind HIB cooperatively How Cul3-based E3 ligases recognize their substrates is to mediate its degradation. We provide evidence that both HIB and unknown, and the specific degrons in their target proteins Ci form dimers/oligomers and engage in multivalent interactions, remain to be identified for individual BTB proteins that function which underlies the in vivo cooperativity among individual HIB- as target-recognition components.
    [Show full text]
  • SCF-Mediated Protein Degradation and Cell Cycle Control
    Oncogene (2005) 24, 2860–2870 & 2005 Nature Publishing Group All rights reserved 0950-9232/05 $30.00 www.nature.com/onc SCF-mediated protein degradation and cell cycle control Xiaolu L Ang1 and J Wade Harper*,1 1Program in Biological and Biomedical Sciences, Department of Pathology, Harvard Medical School, Boston, MA 02115, USA The regulatory step in ubiquitin (Ub)-mediated protein established that targeted protein degradation is a key degradation involves recognition and selection of the conduit for regulating protein levels, what is now most target substrate by an E3 Ub-ligase.E3 Ub-ligases evoke important is being able to understand the specific sophisticated mechanisms to regulate their activity mechanisms as to how this proteolysis contributes to temporally and spatially, including multiple post-transla- the regulation of cell cycle states and phase transitions. tional modifications, combinatorial E3 Ub-ligase path- This review aims to examine how various E3Ub- ways, and subcellular localization.The phosphodegrons of ligases – which are responsible for substrate recognition many substrates incorporate the activities of multiple in the regulatory step of the Ub-mediated proteolytic kinases, and ubiquitination only occurs when all necessary pathway – recognize their targets, and we focus on three phosphorylation signals have been incorporated.In this particular emerging themes in the regulation of Ub- manner, the precise timing of degradation can be mediated proteolysis. Using exemplary findings, we will controlled.Another way that the Ub pathway tightly discuss: (1) how the interaction between the E3Ub- controls the timing of proteolysis is with multiple E3 Ub- ligase and its substrate is often dependent upon ligases acting upon a single target.Lastly, subcellular phosphorylation; (2) how multiple E3Ub-ligases are localization can either promote or prevent degradation by often involved in the targeting of cell cycle proteins; and regulating the accessibility of kinases and E3 Ub-ligases.
    [Show full text]
  • Qt2vr8f2sg Nosplash 1E9a8a43
    Instructions for reviewing your article proof You will need to use Adobe Reader version 7 or above to make comments on this proof, available free from http://get.adobe.com/reader/. Responding to the author query form: Please address each query on the query list, on the proof or in a separate query response list. Editing the proof: Edit the manuscript as necessary, using only the circled tools in the Drawing or Annotation menu. IMPORTANT: All edits must be visible in full on a printed page, or they will be lost in production. Do not use any tool that does not show your changes directly on a printed page. Use Text boxes to add text changes and the drawing tools to indicate insert points or graphics changes. Extensive directions should be addressed in a text box. While most figure edits should be marked on the page, extensive visual changes to figures (e.g., adding scale bars or changes to data) should be accompanied by a new figure file with a written explanation of the changes. Special characters can be inserted into text boxes by pasting from a word processing document or by copying from the list below. α β χ δ ε φ γ η ι ϕ κ λ µ ν ο π θ ρ σ τ υ ϖ ω ξ ψ ζ Α Β Σ Δ Ε Φ Γ Η Ι ϑ Κ Λ Μ Ν Ο Π Θ Ρ Σ Τ Υ ς Ω Ξ Ψ Ζ Å Δ ≥ ≤ ≠ × ± 1° 3ʹ ↑↓ →← RE V IE W The intricate dance of post-translational modifications in the rhythm of life .
    [Show full text]
  • Short Article CAND1 Binds to Unneddylated CUL1 and Regulates
    Molecular Cell, Vol. 10, 1519–1526, December, 2002, Copyright 2002 by Cell Press CAND1 Binds to Unneddylated CUL1 Short Article and Regulates the Formation of SCF Ubiquitin E3 Ligase Complex Jianyu Zheng,1 Xiaoming Yang,1 Despite the importance of cullins in controlling many Jennifer M. Harrell,1 Sophia Ryzhikov,1 essential biological processes, the mechanism that reg- Eun-Hee Shim,1 Karin Lykke-Andersen,2 ulates the cullin-containing ubiquitin E3 ligases remains Ning Wei,2 Hong Sun,1 Ryuji Kobayashi,3 unclear. In SCF, the F box proteins are short-lived pro- and Hui Zhang1,4 teins that undergo CUL1/SKP1-dependent degradation 1Department of Genetics (Wirbelauer et al., 2000; Zhou and Howley, 1998). Dele- Yale University School of Medicine tion of the F box region abolishes the binding of F box 333 Cedar Street proteins to SKP1 and CUL1, and consequently increases 2 Department of Molecular, Cellular, the stability of F box proteins. This substrate-indepen- and Developmental Biology dent proteolysis of F box proteins is likely the result of Yale University autoubiquitination by the ubiquitin E2 and E1 enzymes New Haven, Connecticut 06520 through a CUL1/SKP1-dependent mechanism. 3 Cold Spring Harbor Laboratory The carboxy-terminal ends of cullins are often covalently Cold Spring Harbor, New York 11724 modified by a ubiquitin-like protein, NEDD8/RUB1, and this modification appears to associate with active E3 li- gases (Hochstrasser, 2000). Like ubiquitin modification, Summary neddylation requires E1 (APP-BP1 and UBA3)-activating and E2 (UBC12)-conjugating enzymes (Hochstrasser, The SCF ubiquitin E3 ligase regulates ubiquitin-depen- 2000).
    [Show full text]
  • Cullin 1 (CUL1) (NM 003592) Human Tagged ORF Clone Product Data
    OriGene Technologies, Inc. 9620 Medical Center Drive, Ste 200 Rockville, MD 20850, US Phone: +1-888-267-4436 [email protected] EU: [email protected] CN: [email protected] Product datasheet for RC224650L3 Cullin 1 (CUL1) (NM_003592) Human Tagged ORF Clone Product data: Product Type: Expression Plasmids Product Name: Cullin 1 (CUL1) (NM_003592) Human Tagged ORF Clone Tag: Myc-DDK Symbol: CUL1 Vector: pLenti-C-Myc-DDK-P2A-Puro (PS100092) E. coli Selection: Chloramphenicol (34 ug/mL) Cell Selection: Puromycin ORF Nucleotide The ORF insert of this clone is exactly the same as(RC224650). Sequence: Restriction Sites: SgfI-MluI Cloning Scheme: ACCN: NM_003592 ORF Size: 2328 bp This product is to be used for laboratory only. Not for diagnostic or therapeutic use. View online » ©2021 OriGene Technologies, Inc., 9620 Medical Center Drive, Ste 200, Rockville, MD 20850, US 1 / 3 Cullin 1 (CUL1) (NM_003592) Human Tagged ORF Clone – RC224650L3 OTI Disclaimer: The molecular sequence of this clone aligns with the gene accession number as a point of reference only. However, individual transcript sequences of the same gene can differ through naturally occurring variations (e.g. polymorphisms), each with its own valid existence. This clone is substantially in agreement with the reference, but a complete review of all prevailing variants is recommended prior to use. More info OTI Annotation: This clone was engineered to express the complete ORF with an expression tag. Expression varies depending on the nature of the gene. RefSeq: NM_003592.2 RefSeq Size: 3226 bp RefSeq ORF: 2331 bp Locus ID: 8454 UniProt ID: Q13616, A0A090N7U0, B3KTW0 Domains: CULLIN Protein Families: Druggable Genome Protein Pathways: Cell cycle, Oocyte meiosis, TGF-beta signaling pathway, Ubiquitin mediated proteolysis, Wnt signaling pathway MW: 89.5 kDa This product is to be used for laboratory only.
    [Show full text]
  • Peptidic Degron in EID1 Is Recognized by an SCF E3 Ligase Complex Containing the Orphan F-Box Protein FBXO21
    Peptidic degron in EID1 is recognized by an SCF E3 ligase complex containing the orphan F-box protein FBXO21 Cuiyan Zhanga, Xiaotong Lib, Guillaume Adelmantc,d,e, Jessica Dobbinsf,g, Christoph Geisena,h, Matthew G. Osera, Kai W. Wucherpfenningf,g, Jarrod A. Martoc,d,e, and William G. Kaelin Jr.a,h,1 aDepartment of Medical Oncology, Dana-Farber Cancer Institute and Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02215; bState Key Laboratory for Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China; cDepartment of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215; dBlais Proteomics Center, Dana-Farber Cancer Institute, Boston, MA 02215; eDepartment of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02215; fDepartment of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA 02215; gDepartment of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02215; and hHoward Hughes Medical Institute, Chevy Chase, MD 20815 Contributed by William G. Kaelin Jr., November 9, 2015 (sent for review October 24, 2015; reviewed by Bruce E. Clurman and Joan W. Conaway) EP300-interacting inhibitor of differentiation 1 (EID1) belongs to a small heterodimer partner (SHP) [also called NR0B2 (nuclear protein family implicated in the control of transcription, differentia- receptor subfamily 0, group B, member 2)], which is a transcrip- tion, DNA repair, and chromosomal maintenance. EID1 has a very tional corepressor for various steroid hormone family transcription short half-life, especially in G0 cells. We discovered that EID1 contains factors (11–14). In cell-based models, overexpression of EID1 a peptidic, modular degron that is necessary and sufficient for its likewise represses transcription factors and blocks differentiation polyubiquitylation and proteasomal degradation.
    [Show full text]
  • Ubiquitin Ligases Govern Circadian Periodicity by Degradation of CRY in Nucleus and Cytoplasm
    Competing E3 Ubiquitin Ligases Govern Circadian Periodicity by Degradation of CRY in Nucleus and Cytoplasm Seung-Hee Yoo,1,2 Jennifer A. Mohawk,1,2,7 Sandra M. Siepka,4,7 Yongli Shan,1 Seong Kwon Huh,1 Hee-Kyung Hong,4 Izabela Kornblum,2 Vivek Kumar,1,2 Nobuya Koike,1 Ming Xu,3 Justin Nussbaum,5 Xinran Liu,1,8 Zheng Chen,6 Zhijian J. Chen,2,3 Carla B. Green,1,5 and Joseph S. Takahashi1,2,* 1Department of Neuroscience 2Howard Hughes Medical Institute 3Department of Molecular Biology University of Texas Southwestern Medical Center, Dallas, TX 75390, USA 4Department of Neurobiology, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA 5Department of Biology, University of Virginia, Charlottesville, VA 22904, USA 6Department of Biochemistry and Molecular Biology, University of Texas Health Science Center at Houston, Houston, TX 77030, USA 7These authors contributed equally to this work 8Present address: Department of Cell Biology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520 USA *Correspondence: [email protected] http://dx.doi.org/10.1016/j.cell.2013.01.055 SUMMARY and repress the activity of CLOCK:BMAL1 to inhibit their own transcription (King et al., 1997; Gekakis et al., 1998; Lee et al., Period determination in the mammalian circadian 2001). Bmal1 expression is also regulated by a secondary feed- clock involves the turnover rate of the repressors back loop comprised of the nuclear hormone receptors REV- CRY and PER. We show that CRY ubiquitination ERBa/b and the retinoid-related orphan receptors (Preitner engages two competing E3 ligase complexes that et al., 2002; Cho et al., 2012).
    [Show full text]
  • JFK, a Kelch Domain-Containing F-Box Protein, Links the SCF Complex to P53 Regulation
    JFK, a Kelch domain-containing F-box protein, links the SCF complex to p53 regulation Luyang Sun1, Lei Shi1, Wenqian Li, Wenhua Yu, Jing Liang, Hua Zhang, Xiaohan Yang, Yan Wang, Ruifang Li, Xingrong Yao, Xia Yi, and Yongfeng Shang2 Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, Peking University Health Science Center, Beijing 100191, China Edited by George R. Stark, Cleveland Clinic Foundation, Cleveland, OH, and approved May 6, 2009 (received for review February 20, 2009) The p53 tumor suppressor plays a central role in integrating cellular regulation to our knowledge. Considering the key role of p53 in responses to various stresses. Tight regulation of p53 is thus controlling the G1/S cell cycle checkpoint (6, 7) and the importance essential for the maintenance of genome integrity and normal cell of the SCF complex in regulating the G1/S transition (5), the proliferation. Currently, several ubiquitin ligases, including the existence of such a complex for p53 is plausible. single-subunit RING-finger types—MDM2, Pirh2, and COP1—and As substrate receptors of SCF complexes, F-box proteins the HECT-domain type—ARF-BP1—have been reported to target constitute a large family of eukaryotic proteins that feature an p53 for degradation. Here, we report the identification of a human approximately 40-aa F-box motif (8–11). Although they may Kelch domain-containing F-box protein, JFK. We showed that JFK potentially influence a variety of cellular processes, F-box pro- promotes ubiquitination and degradation of p53. But unlike teins were first described in the SCF complex (9, 12) and have MDM2, Pirh2, COP1, and ARF-BP1, all of which possess an intrinsic since been characterized as an integral subunit of the SCF ligase ubiquitin ligase activity, JFK destabilizes p53 through the assembly complexes.
    [Show full text]
  • CSN-Mediated Deneddylation Differentially Modulates Ci 155 Proteolysis to Promote Hedgehog Signalling Responses
    ARTICLE Received 22 Jul 2010 | Accepted 11 Jan 2011 | Published 8 Feb 2011 DOI: 10.1038/ncomms1185 CSN-mediated deneddylation differentially modulates Ci 155 proteolysis to promote Hedgehog signalling responses June-Tai Wu 1 , 2 , Wei-Hsiang Lin 3 , Wei-Yu Chen1 , Yi-Chun Huang4 , 5 , Chiou-Yang Tang 3 , Margaret S. Ho 3 , Haiwei Pi 4 & Cheng-Ting Chien 1 , 3 , 5 The Hedgehog (Hh) morphogen directs distinct cell responses according to its distinct signalling levels. Hh signalling stabilizes transcription factor cubitus interruptus (Ci) by prohibiting SCF Slimb -dependent ubiquitylation and proteolysis of Ci. How graded Hh signalling confers differential SCF Slimb -mediated Ci proteolysis in responding cells remains unclear. Here, we show that in COP9 signalosome ( CSN ) mutants, in which deneddylation of SCFSlimb is inactivated, Ci is destabilized in low-to-intermediate Hh signalling cells. As a consequence, expression of the low- threshold Hh target gene dpp is disrupted, highlighting the critical role of CSN deneddylation on low-to-intermediate Hh signalling response. The status of Ci phosphorylation and the level of E1 ubiquitin-activating enzyme are tightly coupled to this CSN regulation. We propose that the affi nity of substrate –E3 interaction, ligase activity and E1 activity are three major determinants for substrate ubiquitylation and thereby substrate degradation in vivo . 1 Institute of Molecular Medicine, College of Medicine, National Taiwan University , Taipei 100 , Taiwan . 2 Department of Medical Research, National Taiwan University Hospital , Taipei 100 , Taiwan . 3 Institute of Molecular Biology, Academia Sinica , Taipei 115 , Taiwan . 4 Department of Life Science, Chang-Gung University , Tao-Yuan 333 , Taiwan .
    [Show full text]
  • Degradation of FBXO31 by APC/C Is Regulated by AKT- and ATM-Mediated Phosphorylation
    Degradation of FBXO31 by APC/C is regulated by AKT- and ATM-mediated phosphorylation Srinadh Chopparaa,b,1, Sunil K. Maloniac,d,1, Ganga Sankarana, Michael R. Greenc,d,2, and Manas Kumar Santraa,2 aCancer Biology and Epigenetics Laboratory, National Centre for Cell Science, Ganeshkhind, 411 007 Pune, India; bDepartment of Biotechnology, Pune University, Ganeshkhind, 411 077 Pune, India; cHoward Hughes Medical Institute, University of Massachusetts Medical School, Worcester, MA 01605; and dDepartment of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605 Contributed by Michael R. Green, December 19, 2017 (sent for review April 10, 2017; reviewed by Sathees C. Raghavan and Susanta Roychoudhury) The F-box protein FBXO31 is a tumor suppressor that is encoded in arrest and senescence through transcriptional activation of p21 and 16q24.3, for which there is loss of heterozygosity in various solid other p53 target genes. In p53-deficient cells following genotoxic tumors. FBXO31 serves as the substrate-recognition component of stress, FBXO31 interacts with and mediates degradation of cyclin the SKP/Cullin/F-box protein class of E3 ubiquitin ligases and has D1, an important regulator of the G1/S transition, resulting in G1 been shown to direct degradation of pivotal cell-cycle regulatory arrest (11). FBXO31 has also been shown to target several other proteins including cyclin D1 and the p53 antagonist MDM2. FBXO31 proteins, including the DNA replication factor CDT1 (12), the levels are normally low but increase substantially following genotoxic mitotic regulator FOXM1 (13), and the p38 activator MKK6 (14). stress through a mechanism that remains to be determined.
    [Show full text]