Name: determination of the optimal chromosomal location(s) for a dna element in escherichia coli using a novel transposon-mediated approach
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Forfatterne var finansiert gjennom tilskudd fra Novo Nordisk grunnlaget, Lundbeck grunnlaget og danske National Research Foundation (DNRF120) gjennom Center for bakteriell Stress og utholdenhet (BASP.net).

1. innsamling av Transposon biblioteket Merk: chromosomal DARS2 locus ble klonet i mini Tn 10-basert transposon, NKBOR (på pNKBOR) 21, noe som resulterer i NKBOR:: DARS2 (pJFM1). pNKBOR kan fås online 22. pNKBOR er en R6K-baserte selvmord vektor som krever initiatoren protein π for replikering 23. Plasmider pJFM1 er derfor i stand til å gjenskape i en E. coli belastning (f.eks...

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Metodene som er brukt her utnytter state-of-the-art teknikker for å svare på en vanskelig spørsmål angående den optimale genomisk posisjonen av en genetisk element. Tilfeldige innsetting av genetisk elementet (formidlet av transposon) muliggjør rask og enkel innsamling av kloner, som deretter kan gjøres å konkurrere mot hverandre til å velge for den optimale posisjonen undersøkte genetisk elementet (dvs. fittest klone).
Her DARS2 ble satt inn i mini-Tn10-ba...

Funksjonen av genetiske elementer kan påvirkes av beliggenheten i genomet. I bakterier skyldes dette hovedsakelig forstyrrelser av transkripsjon av nærliggende gener, lokale DNA topologien eller replication-assosiert genet dosering. Spesielt prosessene av utryddelse og segregering er kontrollert, minst i delen, av ikke-koding chromosomal regioner1og den riktige funksjonen av disse regionene avhenger på genomisk plassering/kontekst. I E.coli, eksempler er dif området, kreves for søster kromosom løsning2; KOPS sekvenser, kreves for kromosom segregering3; og datA, DARS1og DARS2 områder, nødvendig for riktig chromosomal replikering kontroll (nedenfor; 4). presenterer vi en metode som tillater for tilfeldig flytting, utvalg og bestemmelse av den optimale genetiske konteksten av enhver genetisk element, eksemplifisert her ved studiet av DARS2 ikke-koding regionen.
E. coli, DnaA er initiativtaker protein ansvarlig for DNA strand åpning på én replikering opprinnelseoriCog rekruttering av helicase DnaB5,6,7. DnaA tilhører AAA+ (dvs. ATPases forbundet med ulike aktiviteter) proteiner og kan binde både ATP og ADP med lignende høy slektskap5. Nivået av DnaAATP topper på innvielsen8, der DnaAATP danner en multimer på oriC som utløser DNA dobbeltsidig åpning9. Etter innvielsen, oriC er gjort utilgjengelig for ny innvielse på grunn av lagring av en mekanisme som involverer binding av SeqA protein til hemimethylated oriC10,11. Under lagring, nivået av DnaAATP er redusert med minst to mekanismer: den regulatoriske inaktivering av DnaA (RIDA)12,13 og datA-avhengige DnaAATP hydrolyse (DDAH)14 ,15. Både RIDA og DDAH fremme konvertering av DnaAATP til DnaAADP. Før en ny runde av innvielsen, DnaAADP aktiveres på nytt til DnaAATP på bestemte DnaA-reaktivere sekvenser (DARS): DARS1 og DARS216,17. Chromosomal datA, DARS1, ogDARS2 er ikke-koding og opptre på en Anstandsdame-lignende måte å modulere DnaAATP/DnaAADP interconversion. Disse regionene, utenfor opprinnelsen til replikering aktiverer montering av en DnaA kompleks for inaktivering (datA, 14) eller Aktivisering (DARS1 og DARS2, 17) av DnaA. Slette DARS2 i en celle, endrer ikke masse dobling tid men resultater i asynkron replikering innvielsen15,16,18. Men DARS2-mangelfull celler har en fitness kostnader i forhold til en ellers isogenic wildtype under både kontinuerlig vekst konkurranse i rike medium eller under etableringen av kolonisering i musen tarmen18. Dette betyr at selv små endringer i asynchrony/opprinnelse konsentrasjon har en negativ effekt på bakteriell fitness. I E. colier en selektiv press for å opprettholde kromosom symmetri (dvs. to nesten like lange replikering armer)19. Dataene, DARS1og DARS2 regioner har samme relative avstanden til oriC i alle E. coli stammer sekvensert18, til tross for store variasjoner i kromosom størrelse.
Her bruker vi DARS2 regionen av E. coli som et eksempel for identifikasjon av chromosomal stillingen(e) optimalt for sin funksjon. DARS2 ble satt inn i den NKBOR transposon, og den resulterende NKBOR::DARS2 transposon deretter inn tilfeldig genomet av MG1655 ΔDARS2. Vi dermed generert en samling celler, hver besittelse DARS2 plassert et annet sted på kromosomet. Et i vitro konkurranse eksperiment der alle cellene i samlingen var samlet og konkurrerte mot hverandre kontinuerlig vekst i LB i en estimert 700 generasjoner, ble utført. Utfallet av konkurransen eksperimentet ble overvåket/bestemt sørlige blot, enkel genet gå og hele-genome sekvensering (WGS; Figur 1). End-Point kloner løses ved enkel genet gå var preget av flowcytometri å vurdere celle syklus parametere. I et flow cytometric analyse, kan Cellestørrelse, DNA innhold og initiering synkronisering måles for et stort antall celler. Under flowcytometri, en strøm av enkeltceller passerer en lysstråle med riktige bølgelengden å opphisse farget DNA, som er deretter samtidig registrert av photomultipliers som samler den slippes ut fluorescensen, et mål på DNA innhold, forutsatt at celler er farget for DNA. Fremover-spredt lyset er et mål på cellen masse20.
I vitro konkurranse eksperimentet vi presenterer her brukes til å løse spørsmål knyttet til betydningen av chromosomal posisjon og genomisk sammenheng med genetisk elementet. Metoden er upartisk og brukervennlig.

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			<td height="20" style="width:369px;height:20px;">Autoclaved Mili-Q water</td>
			<td style="width:164px;"></td>
			<td style="width:119px;">None</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="width:369px;height:20px;">Electroporation Cuvettes, 0.1 cm</td>
			<td style="width:164px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">P41050</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="width:369px;height:20px;">Bio-Rad MicroPulser Electroporation System</td>
			<td style="width:164px;">Bio-Rad</td>
			<td style="width:119px;">165-2100</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="width:369px;height:42px;">LB Broth</td>
			<td style="width:164px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">12780029&#160;</td>
			<td></td>
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		<tr height="20">
			<td height="20" style="width:369px;height:20px;">LB Agar, powder (Lennox L agar)</td>
			<td style="width:164px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">22700025</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="width:369px;height:20px;">Glycerol</td>
			<td style="width:164px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">17904</td>
			<td></td>
		</tr>
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			<td height="21" style="width:369px;height:21px;">Fisherbrand&#160;Plastic Petri Dishes</td>
			<td style="width:164px;">Fisher Scientific</td>
			<td style="width:119px;">S33580A</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Falcon 50mL Conical Centrifuge Tubes</td>
			<td style="width:164px;">Fisher Scientific</td>
			<td style="width:119px;">14-432-22</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Falcon 15mL Conical Centrifuge Tubes</td>
			<td style="width:164px;">Fisher Scientific</td>
			<td style="width:119px;">14-959-53A</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Nunc&#160;CryoTubes</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">V7634&#160;</td>
			<td></td>
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		<tr height="42">
			<td height="42" style="width:369px;height:42px;">Phusion High-Fidelity DNA Polymerase (2 U/&#181;L)</td>
			<td style="width:164px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">F530S</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="width:369px;height:21px;">dATP, [&#945;-32P]- 3000Ci/mmol 10mCi/ml, 250 &#181;Ci</td>
			<td style="width:164px;">PerkinElmer</td>
			<td style="width:119px;">BLU012H250UC</td>
			<td></td>
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		<tr height="42">
			<td height="42" style="width:369px;height:42px;">DECAprime II DNA Labeling Kit</td>
			<td style="width:164px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">AM1455</td>
			<td></td>
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		<tr height="20">
			<td height="20" style="width:369px;height:20px;">Spectrophotometer&#160; SF/MBV/03.32</td>
			<td style="width:164px;">Pharmacia</td>
			<td style="width:119px;"></td>
			<td></td>
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		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Hermle Centrifuge&#160;&#160;&#160; SF/MBV/03.46</td>
			<td style="width:164px;">Hermle</td>
			<td style="width:119px;"></td>
			<td></td>
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		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Ole Dich Centrifuge&#160; SF/MBV/03.29</td>
			<td style="width:164px;">Ole Dich</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Eppendorftubes 1.5 mL</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">T9661</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Eppendorftubes 2.0 mL</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">T2795</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;">Sodium Chloride</td>
			<td>Merck</td>
			<td>6404</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">96% Ethanol</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">16368</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Trizma HCl</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">T-3253</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Phenol Ultra Pure</td>
			<td>BRL</td>
			<td>5509UA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Chloroform</td>
			<td>Merck</td>
			<td>2445</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Ribonuclease A type II A</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td>R5000</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Sodiumdodecylsulphate (SDS)</td>
			<td>Merck</td>
			<td>13760</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Lysozyme</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td>L 6876</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Isopropanol</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td>405-7</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">0.5M Na-EDTA pH 8.0</td>
			<td>BRL</td>
			<td>5575 UA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Kanamycin sulfate</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">10106801001</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="width:369px;height:42px;">PvuI (10 U/&#181;L)</td>
			<td style="width:164px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">ER0621</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="width:369px;height:42px;">UltraPure Agarose</td>
			<td style="width:164px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">16500500</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="width:369px;height:42px;">DNA Gel Loading Dye (6X)</td>
			<td style="width:164px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">R0611</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Tris-Borate-EDTA buffer</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">T4415</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Ethidium bromide</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">E7637</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Hydrochloric acid</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">433160</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Sodium Hydroxide</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">71687</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Whatman&#160;3MM papers</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">WHA3030931</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="width:369px;height:21px;">SSC Buffer 20&#215; Concentrate</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">S6639</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Amersham Hybond-N+</td>
			<td style="width:164px;">GE Healthcare</td>
			<td style="width:119px;">RPN119B</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Ficoll&#160;400</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">F8016</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Polyvinylpyrrolidone</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">PVP40</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Bovine Serum Albumin - Fraction V</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">85040C</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Deoxyribonucleic acid sodium salt from salmon testes</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">D1626</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Carestream Kodak &#160;BioMax &#160;light film</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">Z373494</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">GenElute &#160;Gel Extraction Kit</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">NA1111&#160;</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">GenElute &#160;PCR Clean-Up Kit</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">NA1020</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">T100&#160; Thermal Cycler</td>
			<td style="width:164px;">Bio-Rad</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">SmartSpec Plus Spectrophotometer</td>
			<td style="width:164px;">Bio-Rad</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Rifampicin</td>
			<td style="width:164px;">Serva</td>
			<td style="width:119px;">34514.01</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Cephalexin</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">C4895</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Mithramycin</td>
			<td style="width:164px;">Serva</td>
			<td>29803.02</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Magnesium chloride hexahydrate</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td style="width:119px;">246964</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:369px;height:21px;">Apogee A10 instrument</td>
			<td style="width:164px;">Apogee</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

determination of the optimal chromosomal location(s) for a dna element in escherichia coli using a novel transposon-mediated approach

Den optimale chromosomal stillingen(e) over et gitt DNA element var/ble fastsatt av transposon-mediert tilfeldige innsetting etterfulgt av fitness utvalg. I bakterier, kan virkningen av genetisk sammenheng på funksjon av en genetisk element være vanskelig å vurdere. Flere mekanismer, inkludert topologisk, transcriptional forstyrrelser fra nærliggende gener, og/eller replication-assosiert genet dosering, kan påvirke funksjonen til et gitt genetisk element. Her beskriver vi en metode som tillater tilfeldig integrering av en DNA-element i kromosomet Escherichia coli og velg de mest gunstige lokasjonene ved hjelp av en enkel vekst konkurranse eksperimentere. Metoden utnytter en godt beskrevet transposon-basert system for tilfeldige innsetting, kombinert med et utvalg av de fittest clone(s) av vekst fordel, en prosedyre som lett justerbar eksperimentelle behov. Naturen av de fittest clone(s) kan bestemmes av hele-genome sekvensering på komplekse multi klonal innbyggere eller enkel genet gå i rask identifikasjon av valgte kloner. Her, ble ikke-koding DNA regionen DARS2, som kontrollerer initiering av kromosom replikasjon i E. coli, brukt som et eksempel. Funksjonen for DARS2 er kjent for replikering-assosiert genet dosering; den nærmere DARS2 får opprinnelsen til utryddelse, jo mer aktiv blir. DARS2 var tilfeldig inn kromosomet av en DARS2-slettet belastning. De resulterende Klonene som inneholder personlige innsettinger var samlet og konkurrerte mot hverandre i hundrevis av generasjoner. Endelig var fittest kloner preget og inneholdt DARS2 i nærheten av den opprinnelige DARS2 plasseringen.

En sørlige klatt ble gjort for å bekrefte at DARS2 ble distribuert tilfeldig gjennom kromosomet i transposon biblioteket (t = 0) og som fittest kloner ville vedvarer over tid. Sørlige blot ble utført på DNA utvunnet fra første transposon bassenget (på t = 0) og hver anslagsvis 100 av 700 generasjoner konkurransen (Figur 3). Her totale mobilnettet DNA fra hvert tidspunkt var fordøyd med Pvujeg begrensning enzym, kjent for å kutte tra...

Watch this Scientific Journal Video about Determination of the Optimal Chromosomal Locations for a DNA Element in Escherichia coli Using a Novel Transposon-mediated Approach at JoVE.com

Determination of the Optimal Chromosomal Locations for a DNA Element in Escherichia coli Using a Novel Transposon-mediated Approach

Her, ble kraften av en transposon-mediert tilfeldige innsetting av en ikke-koding DNA-element brukt til å løse optimale chromosomal plasseringen.

Bestemmelse av den optimale Chromosomal plassering(er) gir et DNA i Escherichia coli bruker en ny Transposon-mediert tilnærming

The optimal chromosomal position(s) of a given DNA element was/were determined by transposon-mediated random insertion followed by fitness selection. In ...

Research

JoVE Journal

Genetics

Determination of the Optimal Chromosomal Location(s) for a DNA Element in Escherichia coli Using a Novel Transposon-mediated Approach

Analysis of the Ambient Particulate Matter-induced Chromosomal Aberrations Using an In Vitro System

Analysis of the Ambient Particulate Matter-induced Chromosomal Aberrations Using an In Vitro System

Analyse av Ambient Svevestøv-indusert kromosomavvik ved hjelp av en<em&gt; In Vitro</em&gt; System

Exposure to particulate matter (PM) is a major world health concern, which may damage various cellular components, including the nuclear genetic material. ...

Detection of Copy Number Alterations Using Single Cell Sequencing

Påvisning av Kopier nummer Endringer Bruke enkelt celle Sequencing

Detection of genomic changes at single cell resolution is important for characterizing genetic heterogeneity and evolution in normal tissues, cancers, and ...

Genome-wide Determination of Mammalian Replication Timing by DNA Content Measurement

Genome-wide Fastsettelse av pattedyr Replication Timing av DNA innhold Measurement

Replication of the genome occurs during S phase of the cell cycle in a highly regulated process that ensures the fidelity of DNA duplication. Each genomic ...

Robust DNA Isolation and High-throughput Sequencing Library Construction for Herbarium Specimens

Robust DNA isolasjon og høy gjennomstrømming sekvensering biblioteket konstruksjon for Herbarium prøver

Herbaria are an invaluable source of plant material that can be used in a variety of biological studies. The use of herbarium specimens is associated with ...

A Novel Saturation Mutagenesis Approach: Single Step Characterization of Regulatory Protein Binding Sites in RNA Using Phosphorothioates

En roman metning mutagenese tilnærming: Enkeltsteg karakteristikk av regulatoriske Protein bindende områder i RNA bruker Phosphorothioates

Gene regulation plays an important role in development. Numerous DNA- and RNA-binding proteins bind their target sequences with high specificity to ...

Producing Gene Deletions in Escherichia coli by P1 Transduction with Excisable Antibiotic Resistance Cassettes

Producing Gene Deletions in Escherichia coli by P1 Transduction with Excisable Antibiotic Resistance Cassettes

Produsere Gene slettingene i Escherichia coli av P1 signaltransduksjon med Excisable antibiotikaresistens kassetter

A first approach to study the function of an unknown gene in bacteria is to create a knock-out of this gene. Here, we describe a robust and fast protocol ...

Using In Vitro and In-cell SHAPE to Investigate Small Molecule Induced Pre-mRNA Structural Changes

Bruke i Vitro og i celle form å undersøke små molekyl indusert Pre-mRNA strukturelle endringer

In the process of drug development of RNA-targeting small molecules, elucidating the structural changes upon their interactions with target RNA sequences ...

In vivo Application of the REMOTE-control System for the Manipulation of Endogenous Gene Expression

In vivo anvendelsen av fjernkontroll systemet for manipulering av endogene genuttrykk

Here we describe a protocol for implementing the REMOTE-control system (Reversible Manipulation of Transcription at Endogenous loci), which allows for ...

Mass Spectrometry-Based Proteomics Analyses Using the OpenProt Database to Unveil Novel Proteins Translated from Non-Canonical Open Reading Frames

Masse massespektrometri-baserte Proteomikk analyser bruker OpenProt databasen å avsløre romanen proteiner oversatt fra ikke-kanoniske åpent lesing rammer

Genome annotation is central to today's proteomic research as it draws the outlines of the proteomic landscape. Traditional models of open reading frame ...

Use of Frozen Tissue in the Comet Assay for the Evaluation of DNA Damage

Bruk av frosset vev i kometanalysen for evaluering av DNA-skade

The comet assay is gaining popularity as a means to assess DNA damage in cultured cells and tissues, particularly following exposure to chemicals or other ...