Name: analysis of scap n-glycosylation and trafficking in human cells
Uploaded: 2016-11-08T14:00:00
Description: Watch this Scientific Journal Video about Analysis of SCAP N-glycosylation and Trafficking in Human Cells at JoVE.com

We are grateful to Drs. Mike S. Brown and Joseph L. Goldstein for their agreement to publish this method according to the methods described in their publications. We appreciate Dr. Peter Espenshade for sharing the GFP-SCAP plasmid. This work was supported by NIH grants NS072838 and NS079701 to D.G., American Cancer Society Research Scholar Grant RSG-14-228-01-CSM to D.G., and OSUCCC Pelotonia Postdoctoral Fellowship to C.C. We also appreciate the support from the Ohio State Neuroscience Core (P30 NS038526) and OSUCCC Translational Therapeutic Program seed grant and start-up funds to D.G.

1. Individuazione di endogena SCAP proteine ​​nelle cellule umane <ol><li> Colture cellulari e trattamento <ol><li> Cellule Seed ~ 1 × 10 6 U87 in 10 cm piatto con Modified Eagle Medium di Dulbecco (DMEM) supplementato con siero 5% bovino fetale (FBS) e incubare le cellule a 37 ° C e 5% CO 2 per 24 ore prima del trattamento. </li><li> Lavare le cellule una volta con tampone fosfato salino (PBS), quindi passare cellule per mezzo DMEM fresco con o senza glucosio (5 mM) per 12 hr. </li></ol></...

<ol>
	<li>Ru, P., Williams, T. M., Chakravarti, A., Guo, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tumor+metabolism+of+malignant+gliomas.">Tumor metabolism of malignant gliomas.</a> Cancers (Basel). 5, 1469-1484 (2013).</li><li>Moon, Y. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Scap/SREBP+pathway+is+essential+for+developing+diabetic+fatty+liver+and+carbohydrate-induced+hypertriglyceridemia+in+animals.">The Scap/SREBP pathway is essential for developing diabetic fatty liver and carbohydrate-induced hypertriglyceridemia in animals.</a> Cell metabolism. 15, 240-246 (2012).</li><li>Guo, D., Bell, E. H., Chakravarti, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lipid+metabolism+emerges+as+a+promising+target+for+malignant+glioma+therapy.">Lipid metabolism emerges as a promising target for malignant glioma therapy.</a> CNS Oncology. 2, 289-299 (2013).</li><li>Guo, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+AMPK+agonist+AICAR+inhibits+the+growth+of+EGFRvIII-expressing+glioblastomas+by+inhibiting+lipogenesis.">The AMPK agonist AICAR inhibits the growth of EGFRvIII-expressing glioblastomas by inhibiting lipogenesis.</a> Proceedings of the National Academy of Sciences of the United States of America. , 12932-12937 (2009).</li><li>Menendez, J. A., Lupu, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fatty+acid+synthase+and+the+lipogenic+phenotype+in+cancer+pathogenesis.">Fatty acid synthase and the lipogenic phenotype in cancer pathogenesis.</a> Nat Rev Cancer. 7, 763-777 (2007).</li><li>Guo, D., Cloughesy, T. F., Radu, C. G., Mischel, P. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=AMPK:+A+metabolic+checkpoint+that+regulates+the+growth+of+EGFR+activated+glioblastomas.">AMPK: A metabolic checkpoint that regulates the growth of EGFR activated glioblastomas.</a> Cell Cycle. 9, 211-212 (2010).</li><li>Goldstein, J. L., DeBose-Boyd, R. A., Brown, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Protein+sensors+for+membrane+sterols.">Protein sensors for membrane sterols.</a> Cell. 124, 35-46 (2006).</li><li>Shao, W., Espenshade, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Expanding+Roles+for+SREBP+in+Metabolism.">Expanding Roles for SREBP in Metabolism.</a> Cell metabolism. 16, 414-419 (2012).</li><li>Nohturfft, A., Zhang, S. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coordination+of+lipid+metabolism+in+membrane+biogenesis.">Coordination of lipid metabolism in membrane biogenesis.</a> Annual review of cell and developmental biology. 25, 539-566 (2009).</li><li>Jeon, T. I., Osborne, T. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=SREBPs:+metabolic+integrators+in+physiology+and+metabolism.">SREBPs: metabolic integrators in physiology and metabolism.</a> Trends in endocrinology and metabolism: TEM. 23, 65-72 (2012).</li><li>Sato, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assignment+of+the+membrane+attachment,+DNA+binding,+and+transcriptional+activation+domains+of+sterol+regulatory+element-binding+protein-1+(SREBP-1).">Assignment of the membrane attachment, DNA binding, and transcriptional activation domains of sterol regulatory element-binding protein-1 (SREBP-1).</a> The Journal of biological chemistry. 269, 17267-17273 (1994).</li><li>Sakai, J., Nohturfft, A., Goldstein, J. L., Brown, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cleavage+of+sterol+regulatory+element-binding+proteins+(SREBPs)+at+site-1+requires+interaction+with+SREBP+cleavage-activating+protein.+Evidence+from+in+vivo+competition+studies.">Cleavage of sterol regulatory element-binding proteins (SREBPs) at site-1 requires interaction with SREBP cleavage-activating protein. Evidence from in vivo competition studies.</a> The Journal of biological chemistry. 273, 5785-5793 (1998).</li><li>Sakai, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+complexes+between+the+COOH-terminal+domains+of+sterol+regulatory+element-binding+proteins+(SREBPs)+and+SREBP+cleavage-activating+protein.">Identification of complexes between the COOH-terminal domains of sterol regulatory element-binding proteins (SREBPs) and SREBP cleavage-activating protein.</a> The Journal of biological chemistry. 272, 20213-20221 (1997).</li><li>Hua, X., Nohturfft, A., Goldstein, J. L., Brown, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sterol+resistance+in+CHO+cells+traced+to+point+mutation+in+SREBP+cleavage-activating+protein.">Sterol resistance in CHO cells traced to point mutation in SREBP cleavage-activating protein.</a> Cell. 87, 415-426 (1996).</li><li>Nohturfft, A., Brown, M. S., Goldstein, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Topology+of+SREBP+cleavage-activating+protein,+a+polytopic+membrane+protein+with+a+sterol-sensing+domain.">Topology of SREBP cleavage-activating protein, a polytopic membrane protein with a sterol-sensing domain.</a> The Journal of biological chemistry. 273, 17243-17250 (1998).</li><li>Nohturfft, A., Hua, X., Brown, M. S., Goldstein, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recurrent+G-to-A+substitution+in+a+single+codon+of+SREBP+cleavage-activating+protein+causes+sterol+resistance+in+three+mutant+Chinese+hamster+ovary+cell+lines.">Recurrent G-to-A substitution in a single codon of SREBP cleavage-activating protein causes sterol resistance in three mutant Chinese hamster ovary cell lines.</a> Proc Natl Acad Sci U S A. 93, 13709-13714 (1996).</li><li>Espenshade, P. J., Hughes, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+sterol+synthesis+in+eukaryotes.">Regulation of sterol synthesis in eukaryotes.</a> Annu Rev Genet. 41, 401-427 (2007).</li><li>Yang, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Crucial+step+in+cholesterol+homeostasis:+sterols+promote+binding+of+SCAP+to+INSIG-1,+a+membrane+protein+that+facilitates+retention+of+SREBPs+in+ER.">Crucial step in cholesterol homeostasis: sterols promote binding of SCAP to INSIG-1, a membrane protein that facilitates retention of SREBPs in ER.</a> Cell. 110, 489-500 (2002).</li><li>Yabe, D., Brown, M. S., Goldstein, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insig-2,+a+second+endoplasmic+reticulum+protein+that+binds+SCAP+and+blocks+export+of+sterol+regulatory+element-binding+proteins.">Insig-2, a second endoplasmic reticulum protein that binds SCAP and blocks export of sterol regulatory element-binding proteins.</a> Proc Natl Acad Sci U S A. 99, 12753-12758 (2002).</li><li>Yabe, D., Xia, Z. P., Adams, C. M., Rawson, R. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three+mutations+in+sterol-sensing+domain+of+SCAP+block+interaction+with+insig+and+render+SREBP+cleavage+insensitive+to+sterols.">Three mutations in sterol-sensing domain of SCAP block interaction with insig and render SREBP cleavage insensitive to sterols.</a> Proc Natl Acad Sci U S A. 99, 16672-16677 (2002).</li><li>Espenshade, P. J., Li, W. P., Yabe, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sterols+block+binding+of+COPII+proteins+to+SCAP,+thereby+controlling+SCAP+sorting+in+ER.">Sterols block binding of COPII proteins to SCAP, thereby controlling SCAP sorting in ER.</a> Proceedings of the National Academy of Sciences of the United States of America. 99, 11694-11699 (2002).</li><li>Nohturfft, A., Yabe, D., Goldstein, J. L., Brown, M. S., Espenshade, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulated+step+in+cholesterol+feedback+localized+to+budding+of+SCAP+from+ER+membranes.">Regulated step in cholesterol feedback localized to budding of SCAP from ER membranes.</a> Cell. 102, 315-323 (2000).</li><li>Sakai, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sterol-regulated+release+of+SREBP-2+from+cell+membranes+requires+two+sequential+cleavages,+one+within+a+transmembrane+segment.">Sterol-regulated release of SREBP-2 from cell membranes requires two sequential cleavages, one within a transmembrane segment.</a> Cell. 85, 1037-1046 (1996).</li><li>Wang, X., Sato, R., Brown, M. S., Hua, X., Goldstein, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=SREBP-1,+a+membrane-bound+transcription+factor+released+by+sterol-regulated+proteolysis.">SREBP-1, a membrane-bound transcription factor released by sterol-regulated proteolysis.</a> Cell. 77, 53-62 (1994).</li><li>Brown, M. S., Goldstein, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+proteolytic+pathway+that+controls+the+cholesterol+content+of+membranes,+cells,+and+blood.">A proteolytic pathway that controls the cholesterol content of membranes, cells, and blood.</a> Proceedings of the National Academy of Sciences of the United States of America. 96, 11041-11048 (1999).</li><li>Rawson, R. B., DeBose-Boyd, R., Goldstein, J. L., Brown, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Failure+to+cleave+sterol+regulatory+element-binding+proteins+(SREBPs)+causes+cholesterol+auxotrophy+in+Chinese+hamster+ovary+cells+with+genetic+absence+of+SREBP+cleavage-activating+protein.">Failure to cleave sterol regulatory element-binding proteins (SREBPs) causes cholesterol auxotrophy in Chinese hamster ovary cells with genetic absence of SREBP cleavage-activating protein.</a> J Biol Chem. 274, 28549-28556 (1999).</li><li>Zelenski, N. G., Rawson, R. B., Brown, M. S., Goldstein, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Membrane+topology+of+S2P,+a+protein+required+for+intramembranous+cleavage+of+sterol+regulatory+element-binding+proteins.">Membrane topology of S2P, a protein required for intramembranous cleavage of sterol regulatory element-binding proteins.</a> J Biol Chem. 274, 21973-21980 (1999).</li><li>Goldstein, J. L., Brown, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Century+of+Cholesterol+and+Coronaries:+From+Plaques+to+Genes+to+Statins.">A Century of Cholesterol and Coronaries: From Plaques to Genes to Statins.</a> Cell. 161, 161-172 (2015).</li><li>Espenshade, P. J., Cheng, D., Goldstein, J. L., Brown, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Autocatalytic+processing+of+site-1+protease+removes+propeptide+and+permits+cleavage+of+sterol+regulatory+element-binding+proteins.">Autocatalytic processing of site-1 protease removes propeptide and permits cleavage of sterol regulatory element-binding proteins.</a> The Journal of biological chemistry. 274, 22795-22804 (1999).</li><li>Guo, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=SCAP+links+glucose+to+lipid+metabolism+in+cancer+cells.">SCAP links glucose to lipid metabolism in cancer cells.</a> Mol Cell Oncol. 3, (2016).</li><li>Cheng, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glucose-Mediated+N-glycosylation+of+SCAP+Is+Essential+for+SREBP-1+Activation+and+Tumor+Growth.">Glucose-Mediated N-glycosylation of SCAP Is Essential for SREBP-1 Activation and Tumor Growth.</a> Cancer Cell. 28, 569-581 (2015).</li><li>Shao, W., Espenshade, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sugar+Makes+Fat+by+Talking+to+SCAP.">Sugar Makes Fat by Talking to SCAP.</a> Cancer Cell. 28, 548-549 (2015).</li><li>Guo, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=EGFR+signaling+through+an+Akt-SREBP-1-dependent,+rapamycin-resistant+pathway+sensitizes+glioblastomas+to+antilipogenic+therapy.">EGFR signaling through an Akt-SREBP-1-dependent, rapamycin-resistant pathway sensitizes glioblastomas to antilipogenic therapy.</a> Sci Signal. 2, 82 (2009).</li><li>Guo, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+LXR+agonist+promotes+GBM+cell+death+through+inhibition+of+an+EGFR/AKT/SREBP-1/LDLR-dependent+pathway.">An LXR agonist promotes GBM cell death through inhibition of an EGFR/AKT/SREBP-1/LDLR-dependent pathway.</a> Cancer Discov. 1, 442-456 (2011).</li><li>Guo, D., Bell, E. H., Mischel, P., Chakravarti, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeting+SREBP-1-driven+lipid+metabolism+to+treat+cancer.">Targeting SREBP-1-driven lipid metabolism to treat cancer.</a> Curr Pharm Des. 20, 2619-2626 (2014).</li><li>Bell, E. H., Guo, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biomarkers+for+malignant+gliomas.">Biomarkers for malignant gliomas.</a> Malignant Gliomas, Radiation Medicine Rounds. 3, 339-357 (2012).</li><li>Geng, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inhibition+of+SOAT1+suppresses+glioblastoma+growth+via+blocking+SREBP-1-mediated+lipogenesis.">Inhibition of SOAT1 suppresses glioblastoma growth via blocking SREBP-1-mediated lipogenesis.</a> Clin Cancer Res. , (2016).</li><li>Ru, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Feedback+Loop+Regulation+of+SCAP/SREBP-1+by+miR-29+Modulates+EGFR+Signaling-Driven+Glioblastoma+Growth.">Feedback Loop Regulation of SCAP/SREBP-1 by miR-29 Modulates EGFR Signaling-Driven Glioblastoma Growth.</a> Cell Rep. , (2016).</li><li>Green, M. R., Sambrook, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Molecular Cloning: A Laboratory Manual (Fourth Edition). , (2012).</li><li>Uehara, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=S-nitrosylated+protein-disulphide+isomerase+links+protein+misfolding+to+neurodegeneration.">S-nitrosylated protein-disulphide isomerase links protein misfolding to neurodegeneration.</a> Nature. 441, 513-517 (2006).</li><li>Miyashita, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Confocal+microscopy+for+intracellular+co-localization+of+proteins.">Confocal microscopy for intracellular co-localization of proteins.</a> Methods Mol Biol. 1278, 515-526 (2015).</li><li>Cao, J., Guo, S., Arai, K., Lo, E. H., Ning, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Studying+extracellular+signaling+utilizing+a+glycoproteomic+approach:+lectin+blot+surveys,+a+first+and+important+step.">Studying extracellular signaling utilizing a glycoproteomic approach: lectin blot surveys, a first and important step.</a> Methods Mol Biol. 1013, 227-233 (2013).</li></ol>

In questo studio, si descrive un protocollo per l&#39;isolamento di frazioni di membrana in cellule umane e per la preparazione dei campioni per l&#39;individuazione di -glycosylation SCAP N e proteine totali mediante western blot. Forniamo inoltre un metodo per monitorare il traffico di SCAP utilizzando GFP-etichettatura e la microscopia confocale. Il metodo è specifico per analizzare proteina di membrana ed è uno strumento importante per indagare SCAP N -glycosylation e il traffico. <p class="j...

La deregolamentazione del metabolismo dei lipidi è una caratteristica comune di cancro e metaboliche malattie 1-6. In questi processi, steroli normativi proteine elemento vincolante (SREBPs), una famiglia di fattori di trascrizione, giocano un ruolo critico nel controllo della espressione di geni importanti per l&#39;assorbimento e la sintesi del colesterolo, acidi grassi e fosfolipidi 7-10. SREBPs, tra cui SREBP-1a, SREBP-1c e SREBP-2, sono sintetizzate come precursori inattivi che si legano alla membrana del reticolo endoplasmatico (ER) in virtù di due domini transmembrana 7. L&#39;N-terminale di SREBPs contiene un dominio di legame al DNA per la transattivazione di geni bersaglio 11. Il C-terminale di precursori SREBP lega al SREBP scissione-attivando proteina (SCAP) 12,13, una proteina di membrana politopica che gioca un ruolo fondamentale nella regolazione della stabilità SREBP e l&#39;attivazione 14-16. all&#39;attuazione della funzione trascrizionale richiede la traslocazione del complesso SCAP / SREBP dal pronto soccorso al Golgi, dove due proteasi in sequenza fendono SREBP e rilasciare il suo frammento N-terminale, che entra poi nel nucleo per la transattivazione di geni lipogenici 7. In questi processi, i livelli di steroli nella membrana ER controllano l&#39;uscita del complesso SCAP / SREBP dal ER 7,17. In condizioni di elevate steroli, steroli lega alla SCAP o ER-residente insulino-indotta gene della proteina-1 (Insig-1) o -2 (Insig-2), migliorando l&#39;associazione di SCAP con Insigs che mantengono il complesso SCAP / SREBP nel ER 18-20. Quando i livelli di steroli diminuiscono, SCAP dissocia con Insigs. Questo porta ad un cambiamento conformazionale SCAP, che consente l&#39;interazione con proteine ​​di rivestimento SCAP comuni complesso (COP) II. Il complesso media l&#39;inserimento del complesso SCAP / SREBP nelle vescicole erba e dirige il suo trasporto dal pronto soccorso al Golgi 21,22. Su Transloczione al Golgi, SREBPs vengono sequenzialmente scissi mediante Site-1 e Site-2 proteasi, porta al rilascio del N-terminale 7,23-29. Proteine SCAP trasporta tre N -linked oligosaccaridi a asparagina (N) posiziona N263, N590, N641 e 15. Abbiamo recentemente rivelato che il glucosio-mediata N -glycosylation di SCAP in questi siti è un prerequisito per il traffico di SCAP / SREBP dal pronto soccorso al Golgi in condizioni di bassa steroli 30-32. Perdita di SCAP glicosilazione tramite mutazione di tutti e tre asparagina a glutammina (NNN a qqq) disabilita il traffico del complesso SCAP / SREBP e risultati nella instabilità della proteina SCAP e la riduzione dell&#39;attivazione SREBP 31. I nostri dati recenti dimostrano inoltre che SREBP-1 è altamente attiva nel glioblastoma e regolamentata dalla SCAP N -glycosylation 4,31,33,34. Targeting SCAP / SREBP-1 segnalazione sta emergendo come una nuova strategia per il trattamento di tumori maligni e s metaboliciyndromes 1,3,35-38. Pertanto, è importante sviluppare un metodo efficace per analizzare i livelli di proteina SCAP e N -glycosylation e controllare tale traffico di cellule umane e tessuti del paziente. La regione luminale di proteine SCAP (aminoacidi 540-707) in un pronto soccorso contiene due siti -glycosylation N (N590 e N641) che sono protetti da proteolisi quando membrane intatte sono trattati con tripsina 15. Questo frammento luminale ha un peso molecolare di ~ 30 kDa che è abbastanza piccolo da consentire la risoluzione delle singole varianti glicosilate SCAP da sodio dodecil solfato gel di poliacrilammide (SDS-PAGE) 15,31. Qui, forniamo un metodo per rilevare N -glycosylation della SCAP e proteine totali nelle cellule umane. Questo protocollo è derivato dal metodo descritto nelle pubblicazioni dal laboratorio Brown e Goldstein 15 e la nostra recente pubblicazione 31. Il protocollo può essere utilizzato in tegli lo studio di proteine ​​SCAP da cellule di mammifero.

<table border="0" cellpadding="0" cellspacing="0" width="634">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:259px;">X-treme GENE HP DNA Transfection Reagent&#160;</td>
			<td style="width:163px;">Roche</td>
			<td style="width:123px;">6366236001</td>
			<td style="width:91px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Opti-MEMI medium&#160;</td>
			<td>Life Technologies</td>
			<td>31985-070</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">trypsin&#160;</td>
			<td>Sigma</td>
			<td>T6567</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">soybean trypsin inhibitor</td>
			<td>Sigma</td>
			<td>T9777</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">PNGase F&#160;</td>
			<td>Sigma</td>
			<td>P7367</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Anti-SCAP (9D5) antibody&#160;&#160;</td>
			<td>Santa Cruz</td>
			<td>sc-13553</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">GFP antibody&#160;</td>
			<td>Roche</td>
			<td>11814460001</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">SREBP-1 antibody (IgG-2A4)</td>
			<td>BD Pharmingen</td>
			<td>557036</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">PDI Antibody (H-17)</td>
			<td>Santa Cruz</td>
			<td style="width:123px;">sc-30932</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Lamin A Antibody (H-102)</td>
			<td>Santa Cruz</td>
			<td style="width:123px;">sc-20680</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">SCAP antibody (a.a 450-500)</td>
			<td>Bethyl Laboratories, Inc.</td>
			<td>A303-554A</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Dulbecco&#8217;s modified Eagle&#8217;s medium (DMEM) without glucose, pyruvate and glutamine&#160;&#160;</td>
			<td>Cellgro</td>
			<td>17-207-CV</td>
			<td>Add 1 Mm Pyravate and 4 mM Glutamine before use</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">22G x 1 1/2 needle&#160;</td>
			<td>BD&#160;</td>
			<td>305156</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">pepstatin A</td>
			<td>Sigma</td>
			<td>P5318</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">leupeptin</td>
			<td>Sigma</td>
			<td>L2884</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">PMSF</td>
			<td>Sigma</td>
			<td>P7626</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">DTT</td>
			<td>Sigma</td>
			<td>43819</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">ALLN</td>
			<td>Sigma</td>
			<td>A6185</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Nitrocellulose membrane</td>
			<td>GE</td>
			<td>RPN3032D</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">EDTA Solution 0.5 M PH8.5 100 ml&#160;</td>
			<td>VWR</td>
			<td>82023-102&#160;</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">EGTA 0.5 M sterile (PH 8.0) 50 ml</td>
			<td>Fisher Scentific</td>
			<td>50255956</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">HyClone FBS</td>
			<td>Thermo scientific</td>
			<td>SH3007103</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">glycerol</td>
			<td>Sigma</td>
			<td>G5516</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">&#946;-mercaptoethanol&#160;</td>
			<td>Sigma</td>
			<td>M3148</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">bromophenol blue</td>
			<td>Sigma</td>
			<td>B8026</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">prolong gold antifade reagent with dapi</td>
			<td>life technologies</td>
			<td>P36935</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">L-glutamine (200 mM)</td>
			<td>life technologies</td>
			<td>25030081</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">sodium pyruvate</td>
			<td>life technologies</td>
			<td>11360-070</td>
			<td></td>
		</tr>
	</tbody>
</table>

analysis of scap n-glycosylation and trafficking in human cells

Elevated lipogenesis is a common characteristic of cancer and metabolic diseases. Sterol regulatory element-binding proteins (SREBPs), a family of membrane-bound transcription factors controlling the expression of genes important for the synthesis of cholesterol, fatty acids and phospholipids, are frequently upregulated in these diseases. In the process of SREBP nuclear translocation, SREBP-cleavage activating protein (SCAP) plays a central role in the trafficking of SREBP from the endoplasmic reticulum (ER) to the Golgi and in subsequent proteolysis activation. Recently, we uncovered that glucose-mediated N-glycosylation of SCAP is a prerequisite condition for the exit of SCAP/SREBP from the ER and movement to the Golgi. N-glycosylation stabilizes SCAP and directs SCAP/SREBP trafficking. Here, we describe a protocol for the isolation of membrane fractions in human cells and for the preparation of the samples for the detection of SCAP N-glycosylation and total protein by using western blot. We further provide a method to monitor SCAP trafficking by using confocal microscopy. This protocol is appropriate for the investigation of SCAP N-glycosylation and trafficking in mammalian cells.

La Figura 1 mostra il rilevamento di proteine endogene SCAP e SREBP-1 forma nucleare in cellule glioblastoma U87 umane in risposta al glucosio stimolazione mediante western blot. Il SCAP proteina di membrana viene rilevato nella &quot;frazione di membrana&quot;. La forma nucleo (N-terminale) di SREBP-1 viene rilevata nelle &quot;estratti nucleari&quot;. Il livello di proteine ​​SCAP (PDI funge da controllo interno delle proteine ​​di membrana ER) e SREBP-1 ...

Watch this Scientific Journal Video about Analysis of SCAP N-glycosylation and Trafficking in Human Cells at JoVE.com

Analysis of SCAP N-glycosylation and Trafficking in Human Cells

Descriviamo un metodo modificato per l&#39;isolamento frazione di membrana da cellule umane e preparazione del campione per la rilevazione di -glycosylation SCAP N e proteine totali mediante western blot. Introduciamo inoltre un metodo GFP-etichettatura per monitorare il traffico di SCAP usando la microscopia confocale. Questo protocollo può essere utilizzato in laboratori di biologia regolare.

Analisi di SCAP<em&gt; N</em&gt; -glycosylation E il traffico nelle cellule umane

Elevated lipogenesis is a common characteristic of cancer and metabolic diseases. Sterol regulatory element-binding proteins (SREBPs), a family of ...

Research

JoVE Journal

Biology

Analysis of SCAP N-glycosylation and Trafficking in Human Cells

Video Bioinformatics Analysis of Human Embryonic Stem Cell Colony Growth

Video Bioinformatica Analisi delle embrionali umane crescita Colony cellule staminali

Because video data are complex and are comprised of many images, mining information from video material is difficult to do without the aid of computer ...

Ricerca

Biologia

Phenotypic Analysis and Isolation of Murine Hematopoietic Stem Cells and Lineage-committed Progenitors

L&#39;analisi fenotipica e l&#39;isolamento di murini cellule staminali ematopoietiche e Lineage-committed progenitori

The bone marrow is the principal site where HSCs and more mature blood cells lineage progenitors reside and differentiate in an adult organism. HSCs ...

RNA-seq Analysis of Transcriptomes in Thrombin-treated and Control Human Pulmonary Microvascular Endothelial Cells

RNA-seq Analisi trascrittomi in trombina-trattati e di controllo dell&#39;uomo polmonari cellule endoteliali microvascolari

The characterization of gene expression in cells via measurement of mRNA levels is a useful tool in determining how the transcriptional machinery of the ...

Induction and Analysis of Epithelial to Mesenchymal Transition

Induzione e Analisi dei epiteliale a Mesenchymal Transizione

Epithelial  to mesenchymal transition (EMT) is essential for proper morphogenesis during  development. Misregulation of this  process has been implicated ...

Efficient Generation Human Induced Pluripotent Stem Cells from Human Somatic Cells with Sendai-virus

Efficiente generazione indotta umane pluripotenti cellule staminali da cellule somatiche umane con Sendai-virus

A few years ago, the establishment of human induced pluripotent stem cells (iPSCs) ushered in a new era in biomedicine. Potential uses of human iPSCs ...

Profiling Individual Human Embryonic Stem Cells by Quantitative RT-PCR

Profiling cellule staminali embrionali umane individuale mediante RT-PCR

Heterogeneity of stem cell population hampers detailed understanding of stem cell biology, such as their differentiation propensity toward different ...

Tracking Drug-induced Changes in Receptor Post-internalization Trafficking by Colocalizational Analysis

Rilevamento delle modifiche droga indotte recettore post-internalizzazione Tratta di Analisi Colocalizational

The intracellular trafficking of receptors is a collection of complex and highly controlled processes. Receptor trafficking modulates signaling and ...

High-resolution Time-lapse Imaging and Automated Analysis of Microtubule Dynamics in Living Human Umbilical Vein Endothelial Cells

Ad alta risoluzione Time-lapse imaging e analisi automatizzata dei microtubuli Dynamics in Living ombelicale umano cellule endoteliali Vena

The physiological process by which new vasculature forms from existing vasculature requires specific signaling events that trigger morphological changes ...

Live Cell Imaging and 3D Analysis of Angiotensin Receptor Type 1a Trafficking in Transfected Human Embryonic Kidney Cells Using Confocal Microscopy

Imaging cellulare dal vivo e analisi 3D del recettore dell&#39;angiotensina di tipo 1a tratta degli transfettati embrionali umane cellule renali Utilizzando Microscopia confocale

Live-cell imaging is used to simultaneously capture time-lapse images of angiotensin type 1a receptors (AT1aR) and intracellular compartments in ...

A Graphical User Interface for Software-assisted Tracking of Protein Concentration in Dynamic Cellular Protrusions

Un&#39;interfaccia utente grafica per il monitoraggio assistito della concentrazione di proteine ​​in protrusioni cellulari dinamiche

Filopodia are dynamic, finger-like cellular protrusions associated with migration and cell-cell communication. In order to better understand the complex ...