우리는 (JPV까지) 도자기 재단의 관대 한 선물을 포함하여, 우리의 재원을 감사드립니다 (PJS에) (PJS에) HealthGrant T32-CA079448 및 볼 주립 대학 시작 기금의 국립 연구소. 자금 제공자는 연구 설계, 자료 수집 및 분석, 게시하는 결정, 또는 원고의 준비에 아무런 역할을하지 않았다.

<ol>
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P., McRae, E. K., McKenna, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biochemical+characterization+of+G4+quadruplex+telomerase+RNA+unwinding+by+the+RNA+helicase+RHAU.">Biochemical characterization of G4 quadruplex telomerase RNA unwinding by the RNA helicase RHAU.</a> Methods Mol Biol. 1259, 125-135 (2015).</li><li>Lattmann, S., Giri, B., Vaughn, J. P., Akman, S. A., Nagamine, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+the+amino+terminal+RHAU-specific+motif+in+the+recognition+and+resolution+of+guanine+quadruplex-RNA+by+the+DEAH-box+RNA+helicase+RHAU.">Role of the amino terminal RHAU-specific motif in the recognition and resolution of guanine quadruplex-RNA by the DEAH-box RNA helicase RHAU.</a> Nucleic Acids Res. 38 (18), 6219-6233 (2010).</li></ol>

저자는 공개 아무것도 없어.

이 프로토콜은 DHX36 유전자 산물, G4-Resolvase1 (또한 RHAU 및 DHX36라고 G4R1) (그림 1)의 분리를위한 고효율 발현, 정제 및 정량 방식을 나타냅니다. G4-DNA 접합 구슬에 대한 그의 태그 친 화성 코발트 친 화성 구슬 정화 및 효소 정제 :이 프로토콜은 두 개의 정제 단계를 사용합니다. 후자 단계는 rG4R1는 G4 구조물 가진 꽉 선호도 높은 특이성 및 풀림 촉매 활성을 활용하는 것을 독특하다. G4 구조물 타이트 화성 (낮은 오후 범위 K D는) 상당히 비 - 특이 단백질의 존재를 감소시키는 G4 비드로부터 높은 염 (염화나트륨의 용해도 한계에 가까운) 세탁 전 용출을 허용한다. G4 구조물에 G4R1의 촉매 활성에는 ATP와의 MgCl 2를 첨가시 활성화 rG4R1 특정 용출을 허용한다. 이러한 2 단계의 정제 기법은 일관 고순도 생산대부분의 생화학 적 분석에 적합한 수량 rG4R1 (13) 촉매 활성. 몇 가지 주요 단계는 고순도, 촉매 활성 rG4R1의 좋은 수율을 보장합니다. 첫째, 박테리아 발현 균주로 그의-rG4R1 적절한 유도 조건을 보장한다. 우리는 세포가 유도 직전 이하 0.4-0.6의 OD 600로 성장하는 경우 재조합 단백질의 가장 수율이 발생하는 것으로 나타났습니다. 이 점 이상 세포를 성장하는 가능성으로 인해 봉입체에 rG4R1의 결합에 단백질 복구의 전체 손실이 발생할 수 있습니다. 둘째, 우리는 코발트 친 화성 구슬을 &quot;직렬 결합&quot;해물에 의해 정제 된 단백질의 높은 농도를 획득했습니다. 예를 들어, 우리는 코발트 친 화성 구슬에 의한 문화의 0.5 L에서 해물을 구속하고 같은 코발트 친 화성 구슬에 문화의 추가 0.5 L에서 또 다른 해물의 제 2 결합 수행. 이단계 따라서 코발트 친 화성 비드의 전체 용량을 이용하여 비드의 주어진 부피에 결합 rG4R1 분자의 수를 증가시킴으로써 단백질의 농축 된 제제를 보장한다. 셋째, G4 구슬에 코발트 친 화성 용리 결합 후 높은 소금 세척은 구슬에 결합하는 거의 모든 비 특정 단백질이 제거되도록합니다. 넷째는 ATP /의 MgCl 2 용출 단계는 구슬에서 출시 될 rG4R1을 일으키는 촉매 단일 가닥으로 tetramolecular 구조를 휴식하는 G4 비드에 결합 rG4R1 수 있습니다. 우리는 완전히 ATP 오히려 촉매 방식보다 경쟁에서 rG4R1을 용출 가능성을 배제 할 수 없다; 우리는 이전에 비 분해성 ATP 유사체 13, 18을 결합 경쟁을위한 충분하지 않은 것으로 나타났다 때문에 그러나,이 케이스가 될 가능성이 적다. 풀어진에 대한 rG4R1의 친 화성, 단일 가닥 DNA 덜 t 이상 규모의 순서입니다그는 tetramolecular G4-DNA를 시작하고, 따라서 rG4R1 다시 바인드를 안 구슬에. 이 가능성을 줄이기 위해, 그러나,이 단계는 37 ℃에서 수행되어야하고, 용출 부피가 최대한 빨리 구슬로부터 분리한다. 용출 단계는 최대 복구를 위해 두 번 반복된다. 다운 스트림 응용 프로그램은 DNA의 오염 물질이 없어야하는 단백질을 필요로하는 경우, 우리는 정제 준비가 존재하는 경우, 어떤 바이오틴 DNA를 제거하기 위해 스트렙 타비 딘 비드에 다시 결합되는 추가 정리 단계를 권장합니다. 우리는 적절한 조건이 프로토콜에 걸쳐 유지하지 않는 경우 rG4R1이 저하되기 쉽다 것으로 나타났습니다. 효소의 활성 무결성을 유지하기 위해, 우리는 다음과 같은 중요한 안전 장치를 채용한다. 프로테아제 억제제는 정제 과정을 통해 현재 보관됩니다. 별도로 명시하지 않는 프로토콜은, 4 ° C에서 수행됩니다. 단백질 라의 존재하에 정제하여ctalbumin 및 β-머 캅토 에탄올. 프로토콜은 (정화용 1 일) 적시에 수행된다. 또한, 우리는 다수의 동결 - 해동 사이클에 부정적인 단백질의 활동에 영향을 미치는 것을 발견하고 있으므로 &quot;일회용&quot;로 단백질 나누어지는 7 μL 분취 정제는 다음 -80 ℃에서 보관. 제조에 락트 알부민의 존재는 단백질의 무결성과 활성을 유지하기 위해 필요하지만, 상술 한 바와 같이, 우리는 또한 하류 어플리케이션을 방해 할 수 있음을 발견 하였다. 정제 된 rG4R1 준비에 존재하는 다른 잠재적 인 간섭 분자는 ATP, β-머 캅토 에탄올 및 선발 가닥 DNA를 포함한다. 예를 들어, 인해 버퍼 요소의 높은 배경 신호 BIACORE 분석과 호환 될 수이 단백질 조제를 발견 하였다. 또한, 상기 단백질의 제조에서 락트 알부민의 존재하에 표준 브래드 포드의 사용을 배제및 BCA 단백질 정량 분석. 그러나, 우리는 이러한 한계를 회피하는 다른 겔 기반 정량 방법을 개발 하였다. 구체적를 정화하는 수단으로서 G4R1의 효소 활성을 동력화 이러한 정제 과정은, 다른 방법으로는 구별이 방법을 만든다. 예를 들어, 다른 그룹은 곤충 세포에서 인간 세포 26 (15), (25) 또는 GST-태그 rG4R1에 FLAG 태그가 rG4R1 표명 각각 플래그 - 또는 GST 친 화성 크로마토 그래피하여 정제 하였다. 이러한 방법은 박테리아 발현 시스템에 비해 진핵 세포 발현 시스템에서 수행되는 장점이있다. G4 구조물 얻어진 정제 된 GST-G4R1 예상 K D의 값이 우리보고 K (D)가 12 값보다 13 높은 크기 (14)의 순서로 나타났다. 우리는 생 속성6xHis 태그에 비해 부피가 GST-태그와 연관된 차이로 K d를 값에서의 불일치, 대 세균에 인수 번역 후 변형의 정도와 유형이 두 정화 방식에서 얻은 순도의 차이, 그리고 차이 곤충 발현 시스템. 이 단백질의 정제는 직접 효소 활성에 달려 있기 때문에 우리의 접근은 상기 대안 이상의 뚜렷한 장점을 갖는다. 따라서, 우리는 주로 효소의 특성을 유지하는 방식으로 접혀지고 변형 된 효소를 얻었다. 다른 친 화성 태그 및 / 또는 크기 배제 기술은 효소 죽은 효소의 활성 효소를 분리 할 수 ​​없습니다. 15, 25, 26 (즉, 인간 또는 곤충 세포 익스프레스 다른 그룹의 정화 프로토콜의 장점을 결합하여 미래의 프로토콜 개발에 유용 할 것이다우리의 프로토콜 (즉, 촉매 기반 정제)의 강도와 이온 시스템은) 더이 방법을 개선한다. 이 프로토콜은 G4R1중인 특정이지만, 쉽게 포함한 모든 ATP 의존적 G4 분해하는 단백질에 적합하지만, BLM, WRN, FANCJ, hnRNP 단백질 hPif1 및 / 또는 ChlR1 / DDX1, 이에 한정되지 수있다. 스트렙 타비 딘 비드에 결합 된 핵산의 순서를 변경하여,이 프로토콜은 핵산 헬리 포함한 효소 반응의 생성물은 더 이상 효소에 대한 기질 인 기타 ATP 의존성 핵산 효소를 정제하도록 채택 될 수있다 뉴 클레아.

G4 구조는 DNA와 RNA의 구아닌이 풍부한 지역 내에 형성 안정성이 높은 핵산 차 구조이다. G4 구조 훅 스틴 - 결합 상호 작용을 통해 안정화 크게 G4 구조 (1, 2)의 주목할만한 열적 안정성에 기여하는 가의 양이온 (예. K +와 + 나)와 중앙 공동 내에 결합을 조정한다. 초기 생물 정보학 연구는 인간 게놈&gt; 375,000 &quot;잠재적 인 G4 형성 모티브&quot;3, 4 포함하는 것이 좋습니다. 최근의 연구 평가는 다른 연구는 인간 게놈 6 716310 별개의 잠재적 인 G4 형성 순서를 예측하면서 G4 주제의 수는 2-5 5 배 정도 높은 것이 좋습니다. G4는-형성하는 서열은 진화 적으로 보존 무작위로 분산되지 않습니다게놈. G4 주제는 유전자의 코딩 지역에서 농축되고, 모든 유전자 프로모터의 40 %의 위쪽으로는 G4 모티브 (7)를 포함한다. 흥미롭게도, 유전자의 G4 모티프의 농축 정도는 유전자의 기능을 제시하는 것으로 입증되었다. 예를 들면, 현상에 관여하는 프로토 - 암 유전자 및 유전자는 종양 억제 유전자 8,9보다 G4 구조 훨씬 더 농축있다. 높은 열 안정성으로 게놈 전체에서 거의 어디에나 존재 상당히 중요한 세포 과정에 영향을 미칠 가능성이, 상기 셀은 이러한 구조를 관리하기 위해 효소를 진화 것을 발견 놀랍지이다. 우리는 인간 (헬라) 세포 10 tetramolecular G4-DNA 해결 활동의 대부분의 소스로 특징으로 하나의 효소는 G4 Resolvase1 (또한 RHAU 및 DHX36라고 G4R1)입니다. 그 이후로,이 표시되어 그쪽으로t G4R1 단단히 바인딩 및 촉매 G4 결합 단백질 11, 12, 13에 대한 엄격한보고 된 KDS와 tetramolecular 및 단 분자 G4-DNA와 G4-RNA가 풀릴. 또한 G4R1의 G4 분해하는 활성 텔로미어 / 텔로 머라 생물학 11, 14, 15, 16, 전사 및 접합 17, 18, 19, 20, 개발 21 조혈 포함 생화학 및 세포 과정의 다양한 연루되었는지 (21), 및 면역 조절 22, 23. G4 시퀀스의 우세는 특히 게놈 및 다양한 휴대 페이지에 걸쳐 위치하고로G4R1 최근 표현 효율적이 단백질의 생화학 적 메커니즘과 동작을 밝히기 위해 rG4R1가 매우 중요 할 것이다 활성이 높은 정화 능력에 관여하는 연루되었는지 rocesses. 여기서 우리는 새로운 표현하고 효율적으로 활성 효소를 분리 rG4R1의 ATP 의존, G4-해결 활동을 활용 정화 방식 (그림 1)를 보여줍니다. G4R1 대한 경우와 같이,이 방식은, 효소 반응의 생성물은 더 이상 바인딩 기재되는 다른 ATP 의존성 핵산 효소를 정제하도록 채택 될 수있다.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>TriEx4-DHX36 plasmid</td>
			<td>Addgene</td>
			<td>68368</td>
			<td></td>
		</tr>
		<tr>
			<td>Rosetta2(DE3)plysS competent cells</td>
			<td>Novagen</td>
			<td>71403-4</td>
			<td></td>
		</tr>
		<tr>
			<td>S.O.C medium</td>
			<td>Thermo Fisher Scientific</td>
			<td>15544034&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>Difco Terrific Broth</td>
			<td>Becton Dickinson</td>
			<td>243820</td>
			<td></td>
		</tr>
		<tr>
			<td>Glycerol</td>
			<td>Sigma-Aldrich</td>
			<td>G5516</td>
			<td></td>
		</tr>
		<tr>
			<td>Chloramphenicol</td>
			<td>Sigma-Aldrich</td>
			<td>C1919</td>
			<td>35 &#181;g/ml in bacterial plates/large cultures</td>
		</tr>
		<tr>
			<td>Carbenicillin (plant cell culture tested)</td>
			<td>Sigma-Aldrich</td>
			<td>C3416</td>
			<td>50 &#181;g/ml in bacterial plates/large cultures</td>
		</tr>
		<tr>
			<td>Isopropyl &#946;-D-1-thiogalactopyranoside (IPTG)</td>
			<td>Sigma-Aldrich</td>
			<td>I6758</td>
			<td></td>
		</tr>
		<tr>
			<td>Lysozyme (from chicken egg white)</td>
			<td>Sigma-Aldrich</td>
			<td>L6876</td>
			<td></td>
		</tr>
		<tr>
			<td>1 M Tris-HCl pH=8</td>
			<td>Universal Scientific Supply Co.&#160;</td>
			<td>1963-B</td>
			<td>or From standard source</td>
		</tr>
		<tr>
			<td>1 M Tris-HCl pH=7</td>
			<td>Universal Scientific Supply Co.&#160;</td>
			<td>1966</td>
			<td>or From standard source</td>
		</tr>
		<tr>
			<td>1.5 M Tris-HCl, pH=8.8</td>
			<td></td>
			<td></td>
			<td>For casting resolving gel (for protein quantitation gel); From standard source</td>
		</tr>
		<tr>
			<td>1 M Tris-HCl, pH=6.8</td>
			<td></td>
			<td></td>
			<td>For casting stacking gel (for protein quantitation gel); From standard source</td>
		</tr>
		<tr>
			<td>1 M Tris-Acetate, pH=7.8</td>
			<td>Universal Scientific Supply Co.&#160;</td>
			<td>1981</td>
			<td>or From standard source</td>
		</tr>
		<tr>
			<td>70% Ethanol</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>Magnesium chloride (1 M solution)</td>
			<td>Life Technologies</td>
			<td>AM9530G</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium chloride</td>
			<td>Sigma-Aldrich</td>
			<td>S7653</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium acetate</td>
			<td>Sigma-Aldrich</td>
			<td>S8750</td>
			<td></td>
		</tr>
		<tr>
			<td>20x SSC</td>
			<td>Universal Scientific Supply Co.&#160;</td>
			<td>1665</td>
			<td>or From standard source</td>
		</tr>
		<tr>
			<td>&#946;-mercaptoethanol (2-BME)</td>
			<td>Sigma-Aldrich</td>
			<td>63689</td>
			<td></td>
		</tr>
		<tr>
			<td>Protease inhibitor cocktail</td>
			<td>Sigma-Aldrich</td>
			<td>P8849</td>
			<td></td>
		</tr>
		<tr>
			<td>Leupeptin hemisulfate</td>
			<td>Sigma-Aldrich</td>
			<td>L8511</td>
			<td></td>
		</tr>
		<tr>
			<td>Streptavidin paramagnetic beads</td>
			<td>Promega</td>
			<td>Z5482</td>
			<td></td>
		</tr>
		<tr>
			<td>0.5 M EDTA, pH=8&#160;</td>
			<td>Universal Scientific Supply Co.&#160;</td>
			<td>0718</td>
			<td>or From standard source</td>
		</tr>
		<tr>
			<td>0.2 M EDTA, pH=6</td>
			<td>Universal Scientific Supply Co.&#160;</td>
			<td></td>
			<td>From standard source; initially adjust pH with NaOH, then adjust pH back down with HCl.&#160;&#160;</td>
		</tr>
		<tr>
			<td>A-lactalbumin (Type 1 from bovine milk)</td>
			<td>Sigma-Aldrich</td>
			<td>L5385</td>
			<td></td>
		</tr>
		<tr>
			<td>Cobalt metal affinity beads</td>
			<td>Clonetech</td>
			<td>635502</td>
			<td></td>
		</tr>
		<tr>
			<td>L-Histidine</td>
			<td>Sigma-Aldrich</td>
			<td>H8000</td>
			<td></td>
		</tr>
		<tr>
			<td>Acetic acid, glacial</td>
			<td>Fisher Scientific</td>
			<td>A38-500</td>
			<td></td>
		</tr>
		<tr>
			<td>Adenosine 5&#39;-Triphosphate (from bacterial source)</td>
			<td>Sigma</td>
			<td>A7699</td>
			<td></td>
		</tr>
		<tr>
			<td>40% acrylamide/Bis solution (37.5:1)</td>
			<td>Biorad</td>
			<td>161-0148</td>
			<td></td>
		</tr>
		<tr>
			<td>Glycine</td>
			<td>Sigma-Aldrich</td>
			<td>50046</td>
			<td>to make protein gel running buffer (192 mM glycine, 25 mM Tris Base, 0.1% SDS)</td>
		</tr>
		<tr>
			<td>10 % Sodium dodecyl sulfate&#160;</td>
			<td>Universal Scientific Supply Co.&#160;</td>
			<td>1667</td>
			<td>to make protein gel running buffer (192 mM glycine, 25 mM Tris Base, 0.1% SDS); or From standard source</td>
		</tr>
		<tr>
			<td>10x TBE&#160;</td>
			<td>Sigma-Aldrich</td>
			<td>11666703001</td>
			<td>or From standard source</td>
		</tr>
		<tr>
			<td>Tris base</td>
			<td>Fisher Scientific</td>
			<td>BP152-1</td>
			<td>to make protein gel running buffer (192 mM glycine, 25 mM Tris Base, 0.1% SDS); From standard source</td>
		</tr>
		<tr>
			<td>TEMED</td>
			<td>Sigma-Aldrich</td>
			<td>411019</td>
			<td></td>
		</tr>
		<tr>
			<td>Ammonium persulfate</td>
			<td>Sigma-Aldrich</td>
			<td>A3678</td>
			<td></td>
		</tr>
		<tr>
			<td>Broad Range Protein MW markers</td>
			<td>Promega</td>
			<td>V8491</td>
			<td></td>
		</tr>
		<tr>
			<td>Biotinylated Z33 oligo (&#34;Z33-Bio&#34;)</td>
			<td>Oligos Etc</td>
			<td></td>
			<td>5&#8217; AAA GTG ATG GTG GTG GGG GAA GGA TTC GGA CCT-biotin 3&#8217;</td>
		</tr>
		<tr>
			<td>TAMRA-Z33 oligo (&#34;Z33-TAM&#34;)</td>
			<td>Oligos Etc</td>
			<td></td>
			<td>5&#8217; TAMRA-AAA GTG ATG GTG GTG GGG GAA GGA TTC GGA CCT 3&#8217;</td>
		</tr>
		<tr>
			<td>Fluor-coated TLC plate</td>
			<td>Life Technologies</td>
			<td>AM10110</td>
			<td></td>
		</tr>
		<tr>
			<td>Ficoll</td>
			<td>Sigma-Aldrich</td>
			<td>F2637</td>
			<td>30% in H2O</td>
		</tr>
		<tr>
			<td>Coomassie R-250</td>
			<td>Sigma-Aldrich</td>
			<td>27816</td>
			<td></td>
		</tr>
		<tr>
			<td>Methanol</td>
			<td>Fisher Scientific</td>
			<td>A412</td>
			<td></td>
		</tr>
		<tr>
			<td>Multiband UV lamp</td>
			<td></td>
			<td></td>
			<td>Capable of emitting UV light at 365 nm</td>
		</tr>
		<tr>
			<td>Table-top centrifuge (with swinging bucket rotor)</td>
			<td></td>
			<td></td>
			<td>Capable of being cooled to 4 &#176;C</td>
		</tr>
		<tr>
			<td>Microcentrifuge</td>
			<td></td>
			<td></td>
			<td>Capable of being cooled to 4 &#176;C</td>
		</tr>
		<tr>
			<td>Digital Sonfier</td>
			<td>Branson</td>
			<td></td>
			<td>Or equivalent capable of delivering sonication pulses (30% amplitude, 2s ON 2s OFF)</td>
		</tr>
		<tr>
			<td>50 &#176;C water bath</td>
			<td></td>
			<td></td>
			<td>For formation of Z33 into quadruplex</td>
		</tr>
		<tr>
			<td>37 &#176;C incubator for bacteria</td>
			<td></td>
			<td></td>
			<td>For bacterial transformations and initial overnight growth of large cultures of Rosetta2 E. coli transformed with TriEx4-DHX36</td>
		</tr>
		<tr>
			<td>37 &#176;C/14&#160; &#176;C shaking incubator for bacteria</td>
			<td></td>
			<td></td>
			<td>For growth and protein induction of large cultures of Rosetta2 E. coli transformed with TriEx4-DHX36</td>
		</tr>
		<tr>
			<td>Spectrophotometer</td>
			<td></td>
			<td></td>
			<td>capable of reading OD600; capable of reading oligomer concentrations based on base sequence (such as Biorad SmartSpec 3000)</td>
		</tr>
		<tr>
			<td>Thermometer</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>PCR strip tubes</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>15- and 50-ml centrifuge tubes (polypropylene)</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>Microcentrifuge tubes (2.0 ml)</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>500 ml centrifuge bottles (polypropylene)</td>
			<td>Thermo Scientific</td>
			<td>3141-0500</td>
			<td></td>
		</tr>
		<tr>
			<td>Standard array of pipet tips and serological pipettes</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>Gel-loading tips</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>Automatic repeating pipette</td>
			<td></td>
			<td></td>
			<td>For quick aliquoting of rG4R1; From standard source</td>
		</tr>
		<tr>
			<td>Thermal cycler</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>Liquid Nitrogen</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>Dry ice</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>Laemlli sample buffer&#160;</td>
			<td>Biorad</td>
			<td>161-0737</td>
			<td></td>
		</tr>
		<tr>
			<td>Apparatus for running large slab gels</td>
			<td>Biorad</td>
			<td></td>
			<td>We have used the Protean II xi cell apparatus from Biorad</td>
		</tr>
		<tr>
			<td>Magnet</td>
			<td>Life Technologies</td>
			<td>12301D</td>
			<td>We use a magnet from One Lambda (Now a Thermo Fisher Scientific brand); and Life is also a subsidiary of Thermo, and thus the magnet listed here should be a suitable replacement</td>
		</tr>
		<tr>
			<td>Razor blades</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>Filter paper and funnel</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>Glass casserole dish</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>Orbital shaker</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>Kimwipes</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>Clear sheet protectors</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>Scanner and associated TWAIN software</td>
			<td></td>
			<td></td>
			<td>From standard source</td>
		</tr>
		<tr>
			<td>Image analysis software</td>
			<td></td>
			<td></td>
			<td>Such as Fuji Multiguage, or equivalent</td>
		</tr>
		<tr>
			<td>Microsoft Excel</td>
			<td></td>
			<td></td>
			<td>Or equivalent&#160;</td>
		</tr>
	</tbody>
</table>

a g-quadruplex dna-affinity approach for purification of enzymatically active g4 resolvase1

고차 핵산 구조는 모두 DNA와 RNA의 구아닌이 풍부한 지역에서 형성 할 수있는 G-quadruplexes (G4를, G4 구조)라는 높은 열적으로 안정하다. 이 인간 게놈에&gt; 375,000 추정 G4 형성 서열이 있고, 그들은 프로모터 영역, 번역되지 않은 지역 (UTRs)에 충실하고, 텔로미어 반복 내에서. 때문에 이러한 구조는 복제 및 전사와 같은 세포 과정에 영향을 미칠 가능성이있는 경우에, 셀들을 관리하는 효소를 진화했다. 하나의 효소는 생화학 실험실 및 나가미네 등에 의해 공동으로 특징이었다 G4 Resolvase 1 (G4R1)입니다. 매우 긴밀하게 (낮은 오후 범위에서 K d 개) 모두 G4-DNA와 G4-RNA에 결합하는 것으로. G4R1는 헬라 세포 용 해물에서 G4-해결 활동의 대부분의 원인과 이후 텔로미어 대사, 림프 개발, 유전자 전사, 조혈 및 면역 감시의 역할을 내포하고있다. EF 할 수있는 능력분히 표현하고 촉매 활성 G4R1는 G4의 구조와 G4-해결 효소의 운동의 상호 작용에 더 통찰력을 얻기에 관심이 실험실을 위해 중요하다 정화. 여기, 우리는 재조합 G4R1 (rG4R1)의 정제에 대한 자세한 방법을 설명합니다. 설명 된 절차는 C- 말단 히스티딘 표지 된 효소의 전통적인 선호도 기반 정제 바인딩 및 ATP- 고도로 활성 효소를 정제 G4-DNA를 긴장을 rG4R1 능력의 이용 인간 코돈 최적화 된 세균의 발현 포함 종속 용출 단계. 프로토콜은 또한 rG4R1의 효소 활성 G4-DNA를 푸는 정제 효소의 능력을 조사하여 측정하는 품질 관리 단계를 포함한다. 방법도 정제 rG4R1의 정량화를 허용 것이 기재되어있다. 이 프로토콜의 대체 적응이 논의된다.

이 프로토콜 (그림 1)는 일상적으로 거의 순수, 촉매 활성 rG4R1을 산출한다. rG4R1 0.013 μL 범위 (도 위에서 설명한 G4 활성 분석으로 분석으로서, - TAMRA 표지 tetramolecular G4-DNA 0.2 pmol의 50 %가 0.2 이내에 단량체로 변환되는 효소 활성의 척도로서, 이는 전형적으로 관찰 2). 정제 rG4R1의 쿠마 염색은 G4-DNA 구슬을 결합 할 수 및 ATP 의존에서 용출 능력을 유지하고 그 rG4R1를 절단 나타낼 수 ~ 75 kDa의에서 작은 오염 밴드, 예상되는 120 kDa의 크기로 단일 밴드를 나타냅니다 방법 (그림 3). 관심의 밴드는 단백질 표준 곡선에 대해 정량화하고,이 프로토콜은 일반적으로 세균 배양의 20 ~ 100 nm의 정제 효소 1 당 L 200 μL를 가져옵니다. <img alt="그림 1" src="/files/ftp_upload/55496/55496fig1.jpg" /> 도 1 : G4R1의 2 단계 정제 회로도. 6xHis 태그가 rG4R1는 대량 정제입니다 첫째 결합 및 공동 2 + 구슬을 π 공역 계에서 용출에 의해 대장균 해물에서. G4-DNA 접합 자석 구슬에 바인딩 단계는 다음과 같습니다. 마지막으로, ATP 의존적 용출 단계가 상대적으로 순수한 효소 활성 rG4R1 구하는 것이 필요하다. <a href="https://ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/55496/55496fig1large.jpg" target="_blank">이 그림의 더 큰 버전을 보려면 여기를 클릭하십시오.</a> <img alt="그림 2" src="/files/ftp_upload/55496/55496fig2.jpg" /> 그림 2 : 품질 제어 G4-DNA 풀기 분석. 레인 1-6 : TAMRA 표지 tetramolecular G4-DNA의 일정한 농도를 3.9 μL, 0.83 μL, 0.2 μL, 0.05 μL, 0.013 μL를 나타내는 정제 rG4R1의 배 희석액의 존재 하에서 30 분 동안 37 ℃에서 인큐베이션시켰다 , 0<html> 각각 0.003 μL. 레인 7 : rG4R1의 부재 tetramolecular G4-DNA. 레인 8 : rG4R1의 부재시 단량체로 G4 구조를 줄일 삶은 tetramolecular G4-DNA. <a href="https://ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/55496/55496fig2large.jpg" target="_blank">이 그림의 더 큰 버전을 보려면 여기를 클릭하십시오.</a> <img alt="그림 3" src="/files/ftp_upload/55496/55496fig3.jpg" /> 그림 3 : 정제 rG4R1 농도의 정량화. (6) 각각과의 단백질 농도는 표준 곡선을 생성하는데 사용 하였다 - 레인 1에서 500, 250, 125, 62.5, 31.3, 15.7 NG : 넓은 범위의 MW 단백질 마커는 다음과 같은 양으로 로딩 하였다. 레인 7 rG4R1 35 μL를 나타냅니다. 특정 겔을 62 ± 22 nM의 표준 편차의 평균 단백질 농도에서 얻어진 겔의 삼중 세트의 일부로서, 정량 하였다 (SD; N = 9)..COM / 파일 / ftp_upload / 55496 / 55496fig3large.jpg &quot;대상 =&quot;_ 빈 &quot;&gt;이 그림의 더 큰 버전을 보려면 여기를 클릭하십시오.

Watch this Scientific Journal Video about A G-quadruplex DNA-affinity Approach for Purification of Enzymatically Active G4 Resolvase1 at JoVE.com

A G-quadruplex DNA-affinity Approach for Purification of Enzymatically Active G4 Resolvase1

G4 Resolvase1는 G4 결합 단백질에 대한 소감보고 된 친화 G-quadruplex (G4) 구조에 결합 HeLa 세포에서 G4-DNA 풀기 활동의 대부분을 나타냅니다. 우리는 특히 촉매 활성 재조합 G4R1를 정화 친 화성 및 G4-Resolvase1의 ATP 의존 풀기 활동을 마구를 채우는 새로운 프로토콜을 설명합니다.

효소 활성 G4 Resolvase1의 정화를위한 G-quadruplex DNA 화성 접근

Higher-order nucleic acid structures called G-quadruplexes (G4s, G4 structures) can form in guanine-rich regions of both DNA and RNA and are highly ...

a-g-quadruplex-dna-affinity-approach-for-purification-enzymatically

Nanyang Technological University

Research

JoVE Journal

Biochemistry

9.5K 조회수.  Wake Forest School of Medicine.  G4 Resolvase1는 G4 결합 단백질에 대한 소감보고 된 친화 G-quadruplex (G4) 구조에 결합 HeLa 세포에서 G4-DNA 풀기 활동의 대부분을 나타냅니다. 우리는 특히 촉매 활성 재조합 G4R1를 정화 친 화성 및 G4-Resolvase1의 ATP 의존 풀기 활동을 마구를 채우는 새로운 프로토콜을 설명합니다. 

비디오: A G-quadruplex DNA-affinity Approach for Purification of Enzymatically Active G4 Resolvase1

Directed Protein Packaging within Outer Membrane Vesicles from Escherichia coli: Design, Production and Purification

An increasing interest in applying synthetic biology techniques to program outer membrane vesicles (OMV) are leading to some very interesting and unique applications for OMV where traditional nanoparticles are proving too difficult to synthesize. To date, all Gram-negative bacteria have been shown to produce OMV demonstrating packaging of a variety of cargo that includes small molecules, peptides, proteins and genetic material. Based on their diverse cargo, OMV are implicated in many biological processes ranging from cell-cell communication to gene transfer and delivery of virulence factors depending upon which bacteria are producing the OMV. Only recently have bacterial OMV become accessible for use across a wide range of applications through the development of techniques to control and direct packaging of recombinant proteins into OMV. This protocol describes a method for the production, purification, and use of enzyme packaged OMV providing for improved overall production of recombinant enzyme, increased vesiculation, and enhanced enzyme stability. Successful utilization of this protocol will result in the creation of a bacterial strain that simultaneously produces a recombinant protein and directs it for OMV encapsulation through creating a synthetic linkage between the recombinant protein and an outer membrane anchor protein. This protocol also details methods for isolating OMV from bacterial cultures as well as proper handling techniques and things to consider when adapting this protocol for use for other unique applications such as: pharmaceutical drug delivery, medical diagnostics, and environmental remediation.

Directed Protein Packaging within Outer Membrane Vesicles from Escherichia coli: Design, Production and Purification

A protocol for the production, purification, and use of enzyme packaged outer membrane vesicles (OMV) providing for enhanced enzyme stability for implementation across diverse applications is presented.

에서 외부 막 소포 내에서 감독 단백질 포장<em&gt; 대장균</em&gt; : 디자인, 생산 및 정제

An increasing interest in applying synthetic biology techniques to program outer membrane vesicles (OMV) are leading to some very interesting and unique ...

연구

생화학

A Facile and Efficient Approach for the Production of Reversible Disulfide Cross-linked Micelles

Nanomedicine is an emerging form of therapy that harnesses the unique properties of particles that are nanometers in scale for biomedical application. Improving drug delivery to maximize therapeutic outcomes and to reduce drug-associated side effects are some of the cornerstones of present-day nanomedicine. Nanoparticles in particular have found a wide application in cancer treatment. Nanoparticles that offer a high degree of flexibility in design, application, and production based on the tumor microenvironment are projected to be more effective with rapid translation into clinical practice. The polymeric micellar nano-carrier is a popular choice for drug delivery applications.
In this article, we describe a simple and effective protocol for synthesizing drug-loaded, disulfide cross-linked micelles based on the self-assembly of a well-defined amphiphilic linear-dendritic copolymer (telodendrimer, TD). TD is composed of polyethylene glycol (PEG) as the hydrophilic segment and a thiolated cholic acid cluster as the core-forming hydrophobic moiety attached stepwise to an amine-terminated PEG using solution-based peptide chemistry. Chemotherapy drugs, such as paclitaxel (PTX), can be loaded using a standard solvent evaporation method. The O2-mediated oxidation was previously utilized to form intra-micellar disulfide cross-links from free thiol groups on the TDs. However, the reaction was slow and not feasible for large-scale production. Recently, an H2O2-mediated oxidation method was explored as a more feasible and efficient approach, and it was 96 times faster than the previously reported method. Using this approach, 50 g of PTX-loaded, disulfide cross-linked nanoparticles have been successfully produced with narrow particle size distribution and high drug loading efficiency. The stability of the resulting micelle solution is analyzed using disrupting conditions such as co-incubation with a detergent, sodium dodecyl sulfate, with or without a reducing agent. The drug-loaded, disulfide cross-linked micelles demonstrated less hemolytic activity when compared to their non-cross-linked counterparts.

To deliver cancer drugs to tumor sites with high specificity and reduced side effects, new methods based on nanoparticles are required. Here, we describe disulfide cross-linked micelles that can be easily prepared by hydrogen peroxide-mediated oxidation and are able to dissociate efficiently under a reducing tumor environment to release payloads.

가역 디설파이드 가교 미셀 제조를위한 손쉬운 효율적인 접근법

Nanomedicine is an emerging form of therapy that harnesses the unique properties of particles that are nanometers in scale for biomedical application. ...

Expression, Purification, and Antimicrobial Activity of S100A12

Calgranulin proteins are important mediators of innate immunity and are members of the S100 class of the EF-hand family of calcium binding proteins. Some S100 proteins have the capacity to bind transition metals with high affinity and effectively sequester them away from invading microbial pathogens in a process that is termed "nutritional immunity". S100A12 (EN-RAGE) binds both zinc and copper and is highly abundant in innate immune cells such as macrophages and neutrophils. We report a refined method for the expression, enrichment and purification of S100A12 in its active, metal-binding configuration. Utilization of this protein in bacterial growth and viability analyses reveals that S100A12 has antimicrobial activity against the bacterial pathogen, Helicobacter pylori. The antimicrobial activity is predicated on the zinc-binding activity of S100A12, which chelates nutrient zinc, thereby starving H. pylori which requires zinc for growth and proliferation.

Here, we present a method to express and purify S100A12 (calgranulin C). We describe a protocol to measure its antimicrobial activity against the human pathogen H. pylori.

Calgranulin proteins are important mediators of innate immunity and are members of the S100 class of the EF-hand family of calcium binding proteins. Some ...

Brain Membrane Fractionation: An Ex Vivo Approach to Assess Subsynaptic Protein Localization

Assessing the synaptic protein composition and function constitutes an important challenge in neuroscience. However, it is not easy to evaluate neurotransmission that occurs within synapses because it is highly regulated by dynamic protein-protein interactions and phosphorylation events. Accordingly, when any method is used to study synaptic transmission, a major goal is to preserve these transient physiological modifications. Here, we present a brain membrane fractionation protocol that represents a robust procedure to isolate proteins belonging to different synaptic compartments. In other words, the protocol describes a biochemical methodology to carry out protein enrichment from presynaptic, postsynaptic, and extrasynaptic compartments. First, synaptosomes, or synaptic terminals, are obtained from neurons that contain all synaptic compartments by means of a discontinuous sucrose gradient. Of note, the quality of this initial synaptic membrane preparation is critical. Subsequently, the isolation of the different subsynaptic compartments is achieved with light solubilization using mild detergents at differential pH conditions. This allows for separation by gradient and isopycnic centrifugations. Finally, protein enrichment at the different subsynaptic compartments (i.e., pre-, post- and extrasynaptic membrane fractions) is validated by means of immunoblot analysis using well-characterized synaptic protein markers (i.e., SNAP-25, PSD-95, and synaptophysin, respectively), thus enabling a direct assessment of the synaptic distribution of any particular neuronal protein.

Brain Membrane Fractionation: An Ex Vivo Approach to Assess Subsynaptic Protein Localization

Here, we present a brain membrane fractionation protocol that represents a robust procedure to isolate proteins belonging to different synaptic compartments.

뇌막 분획 화 :<em&gt; Ex Vivo</em&gt; Subsynaptic Protein Localization 평가 방법

Assessing the synaptic protein composition and function constitutes an important challenge in neuroscience. However, it is not easy to evaluate ...

Method for Efficient Refolding and Purification of Chemoreceptor Ligand Binding Domain

Identification of natural ligands of chemoreceptors and structural studies aimed at elucidation of the molecular basis of the ligand specificity can be greatly facilitated by the production of milligram amounts of pure, folded ligand binding domains. Attempts to heterologously express periplasmic ligand binding domains of bacterial chemoreceptors in Escherichia coli (E. coli) often result in their targeting into inclusion bodies. Here, a method is presented for protein recovery from inclusion bodies, its refolding and purification, using the periplasmic dCACHE ligand binding domain of Campylobacter jejuni (C. jejuni) chemoreceptor Tlp3 as an example. The approach involves expression of the protein of interest with a cleavable His6-tag, isolation and urea-mediated solubilisation of inclusion bodies, protein refolding by urea depletion, and purification by means of affinity chromatography, followed by tag removal and size-exclusion chromatography. The circular dichroism spectroscopy is used to confirm the folded state of the pure protein. It has been demonstrated that this protocol is generally useful for production of milligram amounts of dCACHE periplasmic ligand binding domains of other bacterial chemoreceptors in a soluble and crystallisable form.

A procedure is presented for the refolding of the dCACHE periplasmic ligand binding domain of Campylobacter jejuni chemoreceptor Tlp3 from inclusion bodies and the purification to yield milligram quantities of protein.

효율적인 Refolding 및 Chemoreceptor Ligand 바인딩 도메인의 정화 방법

Identification of natural ligands of chemoreceptors and structural studies aimed at elucidation of the molecular basis of the ligand specificity can be ...

Purification and Reconstitution of TRPV1 for Spectroscopic Analysis

Polymodal ion channels transduce multiple stimuli of different natures into allosteric changes; these dynamic conformations are challenging to determine and remain largely unknown. With recent advances in single-particle cryo-electron microscopy (cryo-EM) shedding light on the structural features of agonist binding sites and the activation mechanism of several ion channels, the stage is set for an in-depth dynamic analysis of their gating mechanisms using spectroscopic approaches. Spectroscopic techniques such as electron paramagnetic resonance (EPR) and double electron-electron resonance (DEER) have been mainly restricted to the study of prokaryotic ion channels that can be purified in large quantities. The requirement for large amounts of functional and stable membrane proteins has hampered the study of mammalian ion channels using these approaches. EPR and DEER offer many advantages, including determination of the structure and dynamic changes of mobile protein regions, albeit at low resolution, that might be difficult to obtain by X-ray crystallography or cryo-EM, and monitoring reversible gating transition (i.e., closed, open, sensitized, and desensitized). Here, we provide protocols for obtaining milligrams of functional detergent-solubilized transient receptor potential cation channel subfamily V member 1 (TRPV1) that can be labeled for EPR and DEER spectroscopy.

This article describes specific methods to obtain biochemical quantities of detergent-solubilized TRPV1 for spectroscopic analysis. The combined protocols provide biochemical and biophysical tools that can be adapted to facilitate structural and functional studies for mammalian ion channels in a membrane-controlled environment.

정화 및 분 광 분석에 대 한 TRPV1의 재구성

Polymodal ion channels transduce multiple stimuli of different natures into allosteric changes; these dynamic conformations are challenging to determine ...

Anaerobic Protein Purification and Kinetic Analysis via Oxygen Electrode for Studying DesB Dioxygenase Activity and Inhibition

Oxygen-sensitive proteins, including those enzymes which utilize oxygen as a substrate, can have reduced stability when purified using traditional aerobic purification methods. This manuscript illustrates the technical details involved in the anaerobic purification process, including the preparation of buffers and reagents, the methods for column chromatography in a glove box, and the desalting of the protein prior to kinetics. Also described are the methods for preparing and using an oxygen electrode to perform kinetic characterization of an oxygen-utilizing enzyme. These methods are illustrated using the dioxygenase enzyme DesB, a gallate dioxygenase from the bacterium Sphingobium sp. strain SYK-6.

Here we present a protocol for anaerobic protein purification, anaerobic protein concentration, and subsequent kinetic characterization using an oxygen electrode system. The method is illustrated using the enzyme DesB, a dioxygenase enzyme which is more stable and active when purified and stored in an anaerobic environment.

혐 기성 단백질 정화 및 DesB Dioxygenase 활동을 연구 하 고 억제를 위한 산소 전극을 통해 운동 분석

Oxygen-sensitive proteins, including those enzymes which utilize oxygen as a substrate, can have reduced stability when purified using traditional aerobic ...

Expression and Purification of Nuclease-Free Oxygen Scavenger Protocatechuate 3,4-Dioxygenase

Single molecule (SM) microscopy is used in the study of dynamic molecular interactions of fluorophore labeled biomolecules in real time. However, fluorophores are prone to loss of signal via photobleaching by dissolved oxygen (O2). To prevent photobleaching and extend the fluorophore lifetime, oxygen scavenging systems (OSS) are employed to reduce O2. Commercially available OSS may be contaminated by nucleases that damage or degrade nucleic acids, confounding interpretation of experimental results. Here we detail a protocol for the expression and purification of highly active Pseudomonas putida protocatechuate-3,4-dioxygenase (PCD) with no detectable nuclease contamination. PCD can efficiently remove reactive O2 species by conversion of the substrate protocatechuic acid (PCA) to 3-carboxy-cis,cis-muconic acid. This method can be used in any aqueous system where O2 plays a detrimental role in data acquisition. This method is effective in producing highly active, nuclease free PCD in comparison with commercially available PCD.

Protocatechuate 3,4-dioxygenase (PCD) can enzymatically remove free diatomic oxygen from an aqueous system using its substrate protocatechuic acid (PCA). This protocol describes the expression, purification, and activity analysis of this oxygen scavenging enzyme.

뉴클레아제 없는 산소 제거제 프로토카테의 발현 및 정제 3,4-디옥시게나아제

Single molecule (SM) microscopy is used in the study of dynamic molecular interactions of fluorophore labeled biomolecules in real time. However, ...

A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products

Diterpenoids form a diverse class of small molecule natural products that are widely distributed across the kingdoms of life and have critical biological functions in developmental processes, interorganismal interactions, and environmental adaptation. Due to these various bioactivities, many diterpenoids are also of economic importance as pharmaceuticals, food additives, biofuels, and other bioproducts. Advanced genomics and biochemical approaches have enabled a rapid increase in the knowledge of diterpenoid-metabolic genes, enzymes, and pathways. However, the structural complexity of diterpenoids and the narrow taxonomic distribution of individual compounds in often only a single species remain constraining factors for their efficient production. Availability of a broader range of metabolic enzymes now provide resources for producing diterpenoids in sufficient titers and purity to facilitate a deeper investigation of this important metabolite group. Drawing on established tools for microbial and plant-based enzyme co-expression, we present an easily operated and customizable protocol for the enzymatic production of diterpenoids in either Escherichia coli or Nicotiana benthamiana, and the purification of desired products via silica chromatography and semi-preparative HPLC. Using the group of maize (Zea mays) dolabralexin diterpenoids as an example, we highlight how modular combinations of diterpene synthase (diTPS) and cytochrome P450 monooxygenase (P450) enzymes can be used to generate different diterpenoid scaffolds. Purified compounds can be used in various downstream applications, such as metabolite structural analyses, enzyme structure-function studies, and in vitro and in planta bioactivity experiments.

Here we present easy to use protocols for producing and purifying diterpenoid metabolites through the combinatorial expression of biosynthetic enzymes in Escherichia coli or Nicotiana benthamiana, followed by chromatographic product purification. The resulting metabolites are suitable for various studies including molecular structure characterization, enzyme functional studies, and bioactivity assays.

디테르페노이드 천연제품의 효소 생산 및 정화를 위한 맞춤형 접근법

Diterpenoids form a diverse class of small molecule natural products that are widely distributed across the kingdoms of life and have critical biological ...

Single Cell Analysis Of Transcriptionally Active Alleles By Single Molecule FISH

Gene transcription is an essential process in cell biology, and allows cells to interpret and respond to internal and external cues. Traditional bulk population methods (Northern blot, PCR, and RNAseq) that measure mRNA levels lack the ability to provide information on cell-to-cell variation in responses. Precise single cell and allelic visualization and quantification is possible via single molecule RNA fluorescence in situ hybridization (smFISH). RNA-FISH is performed by hybridizing target RNAs with labeled oligonucleotide probes. These can be imaged in medium/high throughput modalities, and, through image analysis pipelines, provide quantitative data on both mature and nascent RNAs, all at the single cell level. The fixation, permeabilization, hybridization and imaging steps have been optimized in the lab over many years using the model system described herein, which results in successful and robust single cell analysis of smFISH labeling. The main goal with sample preparation and processing is to produce high quality images characterized by a high signal-to-noise ratio to reduce false positives and provide data that are more accurate. Here, we present a protocol describing the pipeline from sample preparation to data analysis in conjunction with suggestions and optimization steps to tailor to specific samples.&#160;

Single molecule RNA fluorescence in situ hybridization (smFISH) is a method to accurately quantify levels and localization of specific RNAs at the single cell level. Here, we report our validated lab protocols for wet-bench processing, imaging and image analysis for single cell quantification of specific RNAs.

단일 분자 물고기에 의한 전사 활성 알레일의 단일 세포 분석

Gene transcription is an essential process in cell biology, and allows cells to interpret and respond to internal and external cues. Traditional bulk ...