PA는 라발 대학의 의학부에서 장학금 &quot;피에르 듀 런드&quot;의 수상자이다. 이 작품은 polysom​​e의 분별이 RMR M 새로운 CIHR 조사 급여 상을 보유하고 혁신 보조금에 대한 캐나다 재단 (MOP - GF091050)를 통해 획득 한 RM은 캐나다 자연 과학 및 공학 연구위원회 (MOP - CG095386)에 의해 지원되었다. 우리는 박사 부부에게 감사의 말씀을 전합니다. 도움이 조언 E. Khandjian, I. Gallouzi, S. 디 마르코와 A. Cammas.

프로토콜 지침을 따른다 라발의 윤리 심사위원회의 승인을. 1. 세포 배양의 준비 및 뇌 조작 <ol><li> 포유류와 초파리 세포 <ol><li> 미국 타입 컬쳐 컬렉션에서 권장하는 헬라에게 자궁 경부암 세포와 슈나이더 초파리 배아 세포를 성장. 낮은 통로에서 세포와 함께 작동합니다. </li><li> 80 % 합류에게 실험 일에 도달하기 위해 플레이트 세포. 최상의 결과를 위해, 각각의 실험 조건에 대한 세포의 ~ 12 × 10 6를 사용합니다. polysom​​e 분석을 위해 추출을하기 전에 적어도 90 분 동안 신선한 완전 배지를 추가하여 변환을 자극한다. </li></ol></li><li> 뇌의 분리 : 생후 9, 16 일 사이에서 나이 든 쥐에서 뇌를 분리합니다. 안락사는 마취 및 자궁 경부 탈구 후 CO 2 흡입을 포함한다. 희생에 따라, 전체 뇌와 어느 장소를 격리 나T -80 ° C에서 직접 즉시 사용할 차가운 PBS 1X로 전송합니다. </li></ol> 2. 밀도의 준비 그라데이션 분별 시스템 <ol><li> 5 분 동안 0.1 % SDS와 튜브 시스템을 씻으십시오. </li><li> DEPC의 물로 세척하기 전에 5 분 동안 RNaseZAP 용액으로 한 후, 5 분 동안 70 % 에탄올로 튜브 시스템을 씻는다. </li><li> 장치의 배관 시스템을 건조시키기 위해 공기 펌프. </li></ol> 자당 그라디언트의 3. 준비 <ol><li> 20 mM 트리스 - 염산의 pH 7.4, 1.25 mM의 MgCl2를 2, 150 밀리미터의 NaCl, 1 mM의 DTT의 15 % 및 55 % 자당 솔루션을합니다. </li><li> 생성 제조자의 지시에 의해 설명 된 것처럼 이전시키면서 ISCO 모델 160 구배를 사용하여 선형 15-55% 자당 구배. 그러나, 그라디언트 기포 나 난류의 생성을 방지하기 위해 잘 TRIS 연동 펌프 속도를 제어하는​​ 것이 중요하다. 사용할 때까지 4 ° C에서 그라디언트를 유지합니다. </li><li> 그라데이션 메이커 프로그램이 실행되는 시간 동안 4 ° C.에 초 원심 분리기를 냉각 </li></ol> 4. 셀의 제조 및 마우스 뇌 추출물 <ol><li> 세포 추출물의 제조 <ol><li> 얼음과 세척 세포에 장소 접시 (들)은 차가운 PBS 1X로 3 배. </li><li> 수확 세포의 pH 7.4, 1.25 mM의 MgCl2를 2, 150 밀리미터의 NaCl, 1 mM의 DTT, 1 % Nonidet의 P40, 5 U / ㎖의 RNase 억제제, 보충에 1 ㎖의 용해 완충액 (20 mM 트리스 - 염산에 (~ 12 × 10 6) 완전한 미니 EDTA없는 프로테아제 억제제 칵테일 정제), 에펜 도르프 튜브로 전송하고, 1CC의 U100 인슐린 주사기 28 G 1 / 2를 통해 그들에게 15 배를 전달하여 잘 섞는다. 세포 용 해물을 15 분 동안 얼음 위에서 쉬게. </li><li> 10X 대물 렌즈를 이용하여 위상차 현미경으로 관찰하여 세포 용해를 평가하기 위해 슬라이드에 세포 용 해물의 몇 방울을 넣어. 만 핵은 볼 수 있어야 더 세포막은 세포 용해 볼 증명 없어야합니다. 컨트롤로 관찰unlysed 세포. </li><li> 4 ° C에서 20 분 동안 11,000 XG에서 원심 분리하여 세포 용 해물을 명확히하고 폴리 리보솜을 포함하는 수용성 해물을 유지합니다. </li></ol></li><li> 마우스 뇌 추출물의 제조 <ol><li> 용해 완충액 2 ㎖와 얼음처럼 차가운 다운스 균질 10 스트로크에 의해 전체 격리 된 뇌 (~ 500 mg)을 균질화하고 4 ℃에서 15 분 동안 11,000 XG에서 원심 분리하여 균질을 명확히 </li><li> 50 % 자당의 쿠션에 상층 액을 넣고 4 ℃에서 TH-641 초 원심 분리기의 회 전자를 사용하여 200,000 XG에서 2 시간 동안 침전 진행 </li><li> 용해 완충액 1 ㎖에서 폴리 리보솜을 포함하는 반투명 펠렛을 재현 탁하고 위아래로 피펫 팅하여 잘 혼합한다. 그라디언트에로드하기 전에 30 분 동안 얼음에 서스펜션 나머지를 보자. </li></ol></li></ol> 5. 자당 그라디언트 및 초 원심 분리에 압축을 풉니 다 넣기 <ol><li> 농도를 측정분광 광도계를 사용하여 세포질 추출물에 존재하는 RNA의. 조심스럽게 천천히 15 % ~ 55 %의 자당 기울기에 ~ 추출물의 20 OD 260 단위를로드합니다. 사용 가능한 공간이 2 ~ 3 MM은 원심 분리하는 동안 튜브를 넘쳐 방지하기 위해 튜브의 표면에가 있는지 확인합니다. </li><li> 4 ℃에서 TH-641 초 원심 분리기의 회 전자를 사용하여 230,000 XG에서 2 시간 30 분 동안 초 원심 분리기를 사용하여 그라데이션을 원심 분리기 원심 분리가 종료되면 튜브를 제거하고 그라디언트를 방해하지 조심스럽게 얼음에 배치합니다. </li></ol> Polysom​​es 프로파일에 대한 세포질 추출물 6. 분별 <ol><li> 제조자에 의해 설명 된대로 (0.5 ML 각) 자동화 밀도 분별 시스템에 자당의 그라디언트를 놓고 분수를 자동으로 분류 및 수집을 진행합니다. </li><li> 254 nm에서 흡광도를 지속적으로 모니터링하여 개별 에펜 도르프 튜브에 각 분획 (~ 500 μL)를 수집합니다. parall에서구배 분별 작업의 엘은 polyribosomal 프로파일 차트 용지에 편집한다. 대안 적으로, polysom​​e 프로파일의 전자 수집을받는 차트 레코더 부속 데이터 획득 유닛을 사용한다. </li><li> 각 실행의 끝에서, 드라이 아이스에 수집 Eppendorfs을 전송합니다. 이 때, 저장소 중 하나는 -80 ° C에서 분수를 수집 또는 다음과 같이 직접 단백질-RNA 복합체를 침전. </li></ol> 7. 단백질 추출 및 분석 <ol><li> 자당 기울기의 수집 된 각 부분에, 100 % 냉 에탄올의 2 볼륨을 추가하고 RNA-단백질 복합체가 -20 ° C 하룻밤에 침전 수 있습니다. </li><li> 원심 분리기는 4 ° C에서 20 분 동안 11,000 XG에 각 RNA-단백질 침전물을 70 % 에탄올로 세척한다. 건조하고 (도 2 참조) 특정 항체를 이용하여 웨스턴 블롯을 진행하기 전에 SDS-PAGE 샘플 버퍼에 침전물을 재현 탁. </li></ol> 8. RNA 추출 및(분석) <ol><li> 7.1 절에서와 같이 RNA-단백질 복합체를 침전. SDS 0.1 %를 함유하는 용해 완충액에 각 RNA-단백질 침전물을 재현 탁. 55 ° C의 물을 욕조에 30 분 동안 2 ㎎ / ㎖ 테 K와 침전물의 단백질 성분을 소화. </li><li> &quot;클로로 페놀&quot;, 클로로포름 2 볼륨, 2 M의 NaOAc의 pH를 4 0.1 볼륨과 20 분 동안 4 ° C에서 10,000 XG에서 원심 분리의 1 볼륨을 추가하여 침전물의 RNA 구성 요소의 압축을 풉니 다. 이소프로판올 1 볼륨과 글리코겐의 0.2 ㎍ / μL를 추가하여 -20 ° C에서 하룻밤 각 샘플의 결과 수성 단계에서 RNA 침전물. 4 ℃에서 10,000 XG에서 1 시간 동안 침전 스핀 70 % 차가운 에탄올로 RNA 펠렛을 씻으십시오. </li><li> 이는 RNAse 무료로 물을 작은 볼륨으로 RNA 펠렛을 Resuspend. 양을 평가 품질 RNA의 분광 광도계를 사용하여. </li></ol>

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W., Garcia-Sanz, 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+Isolation+of+polysome-bound+mRNA+from+solid+tissues+amenable+for+RT-PCR+and+profiling+experiments.">a Isolation of polysome-bound mRNA from solid tissues amenable for RT-PCR and profiling experiments.</a> RNA. 13 (3), 414-421 (2007).</li><li>Thoreen, C. C., Chantranupong, L., Keys, H. R., Wang, T., Gray, N. S., Sabatini, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+unifying+model+for+mTORC1-mediated+regulation+of+mRNA+translation.">A unifying model for mTORC1-mediated regulation of mRNA translation.</a> Nature. 485 (7396), 109-113 (2012).</li><li>Ingolia, N. T., Brar, G. A., Rouskin, S., Mcgeachy, A. M., Weissman, J. 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저자가 공개하는 게 없다.

수 크로스 구배에서 polysome 프로파일 분석은 세포 나 조직으로부터 분리 9,11-14 polysomes의 농도를 분석하여 번역 개시의 측정을 허용한다. 이 기술은 최고 접근 (없는 독특한 경우) 생체 내에서 번역 개시를 측정합니다. 이것은 세포주기 (15) 동안 세포를 성장의 병진 상태를 모니터링하고, 번역 개시에, 바이러스 감염, 저산소증 13,16, 방사선 (17), 화학 약물 요?...

진핵 세포는 지속적으로 빠른 적응 세포 반응을 필요 유해한 생리 학적 및 환경 스트레스 조건의 범위를 발생. 세포 스트레스 반응은 안티 - 생존과 프로 생존 행동 요인 사이의 정확한 균형을 포함한다. 이 균형을 방해하는 것은 암과 신경 퇴행성 질환 등 인간의 병리의 개발을 선도하는 돌이킬 수없는 결과를 초래할 수 있습니다. 스트레스 반응의 제 1 단계를 실시하는 동안, 세포는 mRNA의 번역 수준에서의 유전자 발현의 변화의 조정 제어를 포함하는 계의 생존 경로를 활성화. 진핵 생물의 mRNA의 번역은 번역 개시 인자 (EIFS), 특정 RNA 결합 단백질 (RBDS), 그리고 RNA 분자에서 1 사이의 조정의 상호 작용을 포함하는 복잡한 세포 과정이다. 개시, 신장, 및 종료 : mRNA의 번역은 세 가지 단계로 구분된다. 모두 3 단계 REGU 대상이지만병진 제어 메커니즘 따라서이 단백질 합성의 속도 - 제한 단계를 구성하는 대부분의 번역 개시 위상을 표적 곡선 띠의 외곽에 있음을 주목 메커니즘. 번역 개시 내가 사전 개시 복합체의 형성에 선도적 인, 삼원 복잡하고 40S 리보솜 서브 유닛에 그 이후의 바인딩을 만난 eIF2a.GTP.Met-tRNA의 형성으로 시작하는 높은 주문 프로세스입니다. 다음 단계는 그러한 eIF4F eIF3와 같은 번역 개시 인자의 활성을 수반의 mRNA에 preinitiation 착체의 채용이다. 이렇게 형성된 48S preinitiation 단지는 AUG 개시 코돈을 인식 할 때까지의 mRNA의 5&#39;-비 번역 영역을 스캔을 시작하기 위해이 기계를 가능하게 특정 구조적 변화를 겪는다. 번역 개시 인자의 대부분이어서 해제되고 60S 소단위가 80S을 형성하도록 채용되어 리보솜 복합체 번역, 관할t 어떤 점 단백질 합성의 시작 (그림 1). 상세 한 80S보다 monosome는 소위 polysom​​es (또는 폴리 리보솜)의 제조시에 동일의 mRNA를 번역 할 수있다. 의 mRNA에 polysom​​es의 밀도는 개시, 신장 및 종료 속도를 반영하고, 따라서 특정 성적 증명서의 번역 가능성의 척도이다. 그러나 polysom​​e 프로필은 주로 개시 단계에서 mRNA의 번역의 변화를 평가하는 데 사용됩니다. 여기에서 우리는 번역 개시 억제제와 같은 프로 테아 좀 억제제를 사용했습니다. 이 약물을 가진 암 세포의 치료는 번역 개시 인자 eIF2a 3 인산화 HRI라는 스트레스 키나아제의 활성화에 의해 특징 스트레스 반응을 유도한다. eIF2a의 인산화는 포유 동물 세포 4의 번역 개시의 억제로 이어지는 주요 행사 중 하나입니다.

<table border="0" cellpadding="0" cellspacing="0" width="875">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="21">
			<td style="width:311px;"></td>
			<td style="width:119px;"></td>
			<td style="width:167px;"></td>
			<td height="21" style="height:21px;width:279px;">Cells</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:279px;">HeLa cervical cancer cells</td>
			<td style="width:311px;">American Type Culture Collection (Manassas, VA; ATCC)</td>
			<td>CCL-2</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:279px;">Schneider Drosophila embryonic cells</td>
			<td style="width:311px;">American Type Culture Collection (Manassas, VA; ATCC)</td>
			<td>CRL-1963</td>
			<td></td>
		</tr>
		<tr height="21">
			<td style="width:311px;"></td>
			<td style="width:119px;"></td>
			<td></td>
			<td height="21" style="height:21px;width:279px;">Culture medium and Supplements</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Schneider&#8217;s Drosophila Medium</td>
			<td style="width:311px;">Sigma-Aldrich</td>
			<td>SO146-500ml</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">DMEM</td>
			<td>Life technologies</td>
			<td>11995-073</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">FBS</td>
			<td>Fisher Scientist Scientist</td>
			<td>SH30396-03</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">penicillin/streptomycin</td>
			<td>Life technologies</td>
			<td style="width:119px;">15140122</td>
			<td></td>
		</tr>
		<tr height="21">
			<td style="width:311px;"></td>
			<td style="width:119px;"></td>
			<td></td>
			<td height="21" style="height:21px;width:279px;">Sucrose solutions</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">D-Sucrose</td>
			<td>Fisher Scientist</td>
			<td>BP220-212</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Glycerol</td>
			<td style="width:311px;">Sigma-Aldrich</td>
			<td>49767</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Blue Bromophenol</td>
			<td>Fisher Scientist</td>
			<td>B3925</td>
			<td></td>
		</tr>
		<tr height="21">
			<td style="width:311px;"></td>
			<td style="width:119px;"></td>
			<td></td>
			<td height="21" style="height:21px;width:279px;">Lysis buffer</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Tris Hydrochloride</td>
			<td>Fisher Scientist</td>
			<td>BP153-500</td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:279px;">MgCl2 </td>
			<td style="width:311px;">Sigma-Aldrich</td>
			<td style="width:119px;">M2670-100G</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">NaCl</td>
			<td>Tekniscience</td>
			<td>3624-05</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">DTT</td>
			<td style="width:311px;">Sigma-Aldrich</td>
			<td>D 9779</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Nonidet P40 (Igepal CA-630 )</td>
			<td>MJS Biolynx</td>
			<td>19628</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">SDS</td>
			<td>Tekniscience</td>
			<td>4095-02</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:279px;">RNase inhibitor (RnaseOUT Recombinant Ribonuclease Inhibitor)</td>
			<td>Life technologies</td>
			<td>10777-019</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Antiproteases (complete, mini, EDTA free)</td>
			<td>Roche</td>
			<td>11,836,170,001</td>
			<td></td>
		</tr>
		<tr height="21">
			<td style="width:311px;"></td>
			<td style="width:119px;"></td>
			<td></td>
			<td height="21" style="height:21px;width:279px;">RNA Extraction</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Proteinase K</td>
			<td>Life technologies</td>
			<td style="width:119px;">AM2542</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Phenol: Chloroforme</td>
			<td>Fisher Scientist</td>
			<td style="width:119px;">BP1754I-400</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Chloroforme</td>
			<td style="width:311px;">Fisher Scientist</td>
			<td style="width:119px;">C298-500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Glycogen</td>
			<td>Life technologies</td>
			<td>10814-010</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Isopropanol</td>
			<td style="width:311px;">Acros organics</td>
			<td>327270010</td>
			<td></td>
		</tr>
		<tr height="21">
			<td style="width:311px;"></td>
			<td style="width:119px;"></td>
			<td></td>
			<td height="21" style="height:21px;width:279px;">Antibodies</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">anti-FMRP antibody</td>
			<td colspan="2" style="width:429px;">Fournier et al., Cancer Cell International, 2010</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">anti-Ribosomal Protein L28 antibody</td>
			<td style="width:311px;">Santa Cruz Biotechnology, Inc.</td>
			<td style="width:119px;">SC-50362</td>
			<td></td>
		</tr>
		<tr height="21">
			<td style="width:311px;"></td>
			<td style="width:119px;"></td>
			<td></td>
			<td height="21" style="height:21px;width:279px;">Others</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Proteasome inhibitor : Bortezomib</td>
			<td style="width:311px;">LC Laboratories</td>
			<td style="width:119px;">B-1408</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">DEPC (Diethylpyrocarbonate)</td>
			<td style="width:311px;">Sigma-Aldrich</td>
			<td>D5758-25ml</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">RNaseZAP Solution</td>
			<td>Life technologies</td>
			<td style="width:119px;">AM9780</td>
			<td></td>
		</tr>
		<tr height="21">
			<td style="width:311px;"></td>
			<td style="width:119px;"></td>
			<td></td>
			<td height="21" style="height:21px;width:279px;">Materials</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">T25 cell culture flask</td>
			<td style="width:311px;">Corning</td>
			<td style="width:119px;">430639</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">1cc U100 Insulin Syringe 28 G1/2</td>
			<td>Fisher Scientist</td>
			<td>148291B</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Tube ultra-centrifugation, PA, 12ml</td>
			<td>Fisher Scientist</td>
			<td>FSSP9763205</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Isco Model 160 gradient former</td>
			<td style="width:311px;">Teledyne Isco, Lincoln, NE, USA</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Ultracentrifuge Sorvall OTD Combi</td>
			<td style="width:311px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Thermo Scientific Sorvall Rotor TH-641</td>
			<td style="width:311px;">Thermo scientific</td>
			<td style="width:119px;">54295</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Automated Density Fractionation System</td>
			<td style="width:311px;">Teledyne Isco, Lincoln, NE, USA</td>
			<td style="width:119px;">67-9000-177</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Isco UA-6 UV-vis detector</td>
			<td style="width:311px;">Teledyne Isco, Lincoln, NE, USA</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:279px;">NanoDrop 2000 UV-Vis Spectrophotometer</td>
			<td style="width:311px;">Thermo scientific</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Ultracentrifuge C 5415</td>
			<td style="width:311px;">Eppendorf</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:279px;">Optical Microscope</td>
			<td style="width:311px;">Olympus CK2</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

analysis of translation initiation during stress conditions by polysome profiling

mRNA의 번역의 정확한 제어는 특히 생리 학적 및 병리학 적 스트레스에 대한 응답으로, 진핵 세포의 항상성을 위해 필수적입니다. 이 프로그램의 변경은 암 발달의 특징, 또는 신경 퇴행성 질환에서와 같이 조기 세포의 죽음에 손상된 세포의 성장으로 이어질 수 있습니다. 병진 제어를위한 분자 기초 관련된 알려진 정보의 대부분은 밀도 구배 분별 시스템을 사용 polysom​​e 분석으로부터 수득되었다. 이 기술은 선형 자당 기울기에 세포질 추출물을 원심 분리에 의존합니다. 스핀이 완료되면, 시스템은 다른 번역에 대응하는 원심 분리 영역 분별하고 정량화 따라서 polysom​​e 프로파일의 결과 인구 리보솜 허용한다. polysom​​e 프로파일의 변화는 스트레스의 여러 유형에 대한 응답으로 발생 번역 개시의 변화 또는 결함을 나타내는 수 있습니다. 이 기술은 또한 일을 평가 할 수 있습니다전자 번역 개시에 특정 단백질의 역할, 특정의 mRNA의 번역 활동을 측정 할 수 있습니다. 여기에서 우리는 정상 또는 스트레스도 성장​​ 조건에서 진핵 세포와 조직의 번역 개시를 평가하기 위해 polysom​​e 프로파일을 수행하기 위해 프로토콜을 설명합니다.

전술 한 바와 같이, polysome 프로필은 스트레스 조건 하에서 번역 개시의 변화의 분석. 한 이전 번역 개시 복합체의 정렬 어셈블리를 포함하는 다단계 공정되는 바와 같은 번역 개시의 개략적 인도 허용한다. 정상적인 성장 조건에서 번역 개시 복합체는 그 검출 polysome 프로파일에 의해 활성 번역 개시 (; 처리되지 않은 그림 2)에 대한 증명 폴리 리보솜으로 변?...

Watch this Scientific Journal Video about Analysis of Translation Initiation During Stress Conditions by Polysome Profiling at JoVE.com

Analysis of Translation Initiation During Stress Conditions by Polysome Profiling

여기, 우리는 조건을 강조하는 응답 진핵 세포의 mRNA의 번역 개시의 변화를 분석하는 방법을 설명합니다. 이 방법은 비 번역 리보솜에서 리보솜을 번역 자당 기울기의 속도 분리에 근거한다.

Polysom​​e 프로파일에 의한 스트레스 조건에서 번역 개시 분석

Precise control of mRNA translation is fundamental for eukaryotic cell homeostasis, particularly in response to physiological and pathological stress. ...

analysis-translation-initiation-during-stress-conditions-polysome

Research

JoVE Journal

Biology

18.2K 조회수.  Laval University.  여기, 우리는 조건을 강조하는 응답 진핵 세포의 mRNA의 번역 개시의 변화를 분석하는 방법을 설명합니다. 이 방법은 비 번역 리보솜에서 리보솜을 번역 자당 기울기의 속도 분리에 근거한다. 

비디오: Analysis of Translation Initiation During Stress Conditions by Polysome Profiling

Monitoring Plant Hormones During Stress Responses

Plant hormones and related signaling compounds play an important role in the regulation of plant responses to various environmental stimuli and stresses. Among the most severe stresses are insect herbivory, pathogen infection, and drought stress. For each of these stresses a specific set of hormones and/or combinations thereof are known to fine-tune the responses, thereby ensuring the plant's survival. The major hormones involved in the regulation of these responses are jasmonic acid (JA), salicylic acid (SA), and abscisic acid (ABA). To better understand the role of individual hormones as well as their potential interaction during these responses it is necessary to monitor changes in their abundance in a temporal as well as in a spatial fashion. For the easy, sensitive, and reproducible quantification of these and other signaling compounds we developed a method based on vapor phase extraction and gas chromatography/mass spectrometry (GC/MS) analysis (1, 2, 3, 4). After extracting these compounds from the plant tissue by acidic aqueous 1-propanol mixed with dichloromethane the carboxylic acid-containing compounds are methylated, volatilized under heat, and collected on a polymeric absorbent. After elution into a sample vial the analytes are separated by gas chromatography and detected by chemical ionization mass spectrometry. The use of appropriate internal standards then allows for the simple quantification by relating the peak areas of analyte and internal standard.

A simple method is provided that allows for the rapid extraction and analysis of multiple plant hormones from small tissue samples. The procedure uses vapor phase extraction as the solemn purification step. Samples are analyzed by GC/MS with chemical ionization that produces mainly (M+1)+ ions.

스트레스 응답하는 동안 식물 호르몬을 모니터링

Plant hormones and related signaling compounds play an important role in the regulation of plant responses to various environmental stimuli and stresses. ...

연구

생물학

Antibody Profiling by Luciferase Immunoprecipitation Systems (LIPS)

Technologies for comprehensively understanding and quantifying antibody profiles to autoantigens and infectious agents may yield new insights into disease mechanisms and may elucidate new markers to substratify disease with different clinical features and better understand pathogenesis. We have developed a highly quantitative method called Luciferase Immunoprecipitation Systems (LIPS) for profiling patient sera antibody responses to autoantigens and pathogen antigens associated with infection. Unlike ELISAs, the highly sensitive LIPS is easily implemented to survey humoral serological response profiles to different antigens in a universal format and produces dynamic antibody titer ranges up to 6 log10 for some antigens. In these studies, quantitative profiling by LIPS of patient humoral responses against panels of antigens or even the entire proteome of some pathogens (i.e. HIV), is typically more informative than testing a single antigen by ELISA. In addition, LIPS also eliminates time and effort needed to produce highly purified antigens as well as the labor-intensive assay optimization steps needed for standard ELISAs. Here we provide a detailed protocol describing the technical aspects of performing LIPS assays for readily profiling antibody responses to single or multiple antigens.

Antibody Profiling by Luciferase Immunoprecipitation Systems LIPS

The technical aspects of performing LIPS (Luciferase Immunoprecipitation Systems) are described. The overall approach involves expressing chimeric genes encoding antigens fused to Renilla luciferase (Ruc) in mammalian cells. Crude Ruc-antigen extracts are then prepared and, without purification, employed in immunoprecipitation assays to quantify antibodies.

루시페라제 Immunoprecipitation 시스템 (입술)에 의해 항체 프로파일

Technologies for comprehensively understanding and quantifying antibody profiles to autoantigens and infectious agents may yield new insights into disease ...

Analysis of Oxidative Stress in Zebrafish Embryos

High levels of reactive oxygen species (ROS) may cause a change of cellular redox state towards oxidative stress condition. This situation causes oxidation of molecules (lipid, DNA, protein) and leads to cell death. Oxidative stress also impacts the progression of several pathological conditions such as diabetes, retinopathies, neurodegeneration, and cancer. Thus, it is important to define tools to investigate oxidative stress conditions not only at the level of single cells but also in the context of whole organisms. Here, we consider the zebrafish embryo as a useful in vivo system to perform such studies and present a protocol to measure in vivo oxidative stress. Taking advantage of fluorescent ROS probes and zebrafish transgenic fluorescent lines, we develop two different methods to measure oxidative stress in vivo: i) a &#8220;whole embryo ROS-detection method&#8221; for qualitative measurement of oxidative stress and ii) a &#8220;single-cell&#160;ROS detection method&#8221; for quantitative measurements of oxidative stress. Herein, we demonstrate the efficacy of these procedures by increasing oxidative stress in tissues by oxidant agents and physiological or genetic methods. This protocol is amenable for forward genetic screens and it will help address cause-effect relationships of ROS in animal models of oxidative stress-related pathologies such as neurological disorders and cancer.

Here we report a protocol to measure oxidative stress in living zebrafish embryos. This procedure allows reactive oxygen species (ROS) detection in both whole embryo tissues and single-cell populations. This protocol will accomplish both qualitative and quantitative analyses.

제브라 피쉬 배아에서 산화 스트레스의 분석

High levels of reactive oxygen species (ROS) may cause a change of cellular redox state towards oxidative stress condition. This situation causes ...

Polysome Fractionation and Analysis of Mammalian Translatomes on a Genome-wide Scale

mRNA translation plays a central role in the regulation of gene expression and represents the most energy consuming process in mammalian cells. Accordingly, dysregulation of mRNA translation is considered to play a major role in a variety of pathological states including cancer. Ribosomes also host chaperones, which facilitate folding of nascent polypeptides, thereby modulating function and stability of newly synthesized polypeptides. In addition, emerging data indicate that ribosomes serve as a platform for a repertoire of signaling molecules, which are implicated in a variety of post-translational modifications of newly synthesized polypeptides as they emerge from the ribosome, and/or components of translational machinery. Herein, a well-established method of ribosome fractionation using sucrose density gradient centrifugation is described. In conjunction with the in-house developed &#8220;anota&#8221; algorithm this method allows direct determination of differential translation of individual mRNAs on a genome-wide scale. Moreover, this versatile protocol can be used for a variety of biochemical studies aiming to dissect the function of ribosome-associated protein complexes, including those that play a central role in folding and degradation of newly synthesized polypeptides.

Ribosomes play a central role in protein synthesis. Polyribosome (polysome) fractionation by sucrose density gradient centrifugation allows direct determination of translation efficiencies of individual mRNAs on a genome-wide scale. In addition, this method can be used for biochemical analysis of ribosome- and polysome-associated factors such as chaperones and signaling molecules.

게놈 전체 규모에 Polysom​​e 분별과 포유류 Translatomes 분석

mRNA translation plays a central role in the regulation of gene expression and represents the most energy consuming process in mammalian cells. ...

Assessment of Selective mRNA Translation in Mammalian Cells by Polysome Profiling

Regulation of protein synthesis represents a key control point in cellular response to stress. In particular, discreet RNA regulatory elements were shown to allow to selective translation of specific mRNAs, which typically encode for proteins required for a particular stress response. Identification of these mRNAs, as well as the characterization of regulatory mechanisms responsible for selective translation has been at the forefront of molecular biology for some time. Polysome profiling is a cornerstone method in these studies. The goal of polysome profiling is to capture mRNA translation by immobilizing actively translating ribosomes on different transcripts and separate the resulting polyribosomes by ultracentrifugation on a sucrose gradient, thus allowing for a distinction between highly translated transcripts and poorly translated ones. These can then be further characterized by traditional biochemical and molecular biology methods. Importantly, combining polysome profiling with high throughput genomic approaches allows for a large scale analysis of translational regulation.

The ability of cells to adapt to stress is crucial for their survival. Regulation of mRNA translation is one such adaptation strategy, providing for rapid regulation of the proteome. Here, we provide a standardized polysome profiling protocol to identify specific mRNAs that are selectively translated under stress conditions.

Polysom​​e 프로파일 링 포유 동물 세포에 선택적 mRNA의 번역 평가

Regulation of protein synthesis represents a key control point in cellular response to stress. In particular, discreet RNA regulatory elements were shown ...

Fecal Glucocorticoid Analysis: Non-invasive Adrenal Monitoring in Equids

Adrenal activity can be assessed in the equine species by analysis of feces for corticosterone metabolites. During a potentially aversive situation, corticotrophin releasing hormone (CRH) is released from the hypothalamus in the brain. This stimulates the release of adrenocorticotrophic hormone (ACTH) from the pituitary gland, which in turn stimulates release of glucocorticoids from the adrenal gland. In horses the glucocorticoid corticosterone is responsible for several adaptations needed to support equine flight behaviour and subsequent removal from the aversive situation. Corticosterone metabolites can be detected in the feces of horses and assessment offers a non-invasive option to evaluate long term patterns of adrenal activity. Fecal assessment offers advantages over other techniques that monitor adrenal activity including blood plasma and saliva analysis. The non-invasive nature of the method avoids sampling stress which can confound results. It also allows the opportunity for repeated sampling over time and is ideal for studies in free ranging horses. This protocol describes the enzyme linked immunoassay (EIA) used to assess feces for corticosterone, in addition to the associated biochemical validation.

Adrenal activity can be assessed in the equine species by analysis of feces for corticosterone metabolites. The method offers a non-invasive option to assess long term patterns in both domestic and free ranging horses. This protocol describes the enzyme linked immunoassay involved and the associated biochemical validation.

대변​​ 글루코 코르티코이드 분석 : equids는 비 침습적 부신 모니터링

Adrenal activity can be assessed in the equine species by analysis of feces for corticosterone metabolites. During a potentially aversive situation, ...

An Easy Method for Plant Polysome Profiling

Translation of mRNA to protein is a fundamental and highly regulated biological process. Polysome profiling is considered as a gold standard for the analysis of translational regulation. The method described here is an easy and economical way for fractionating polysomes from various plant tissues. A sucrose gradient is made without the need for a gradient maker by sequentially freezing each layer. Cytosolic extracts are then prepared in a buffer containing cycloheximide and chloramphenicol to immobilize the cytosolic and chloroplastic ribosomes to mRNA and are loaded onto the sucrose gradient. After centrifugation, six fractions are directly collected from the bottom to the top of the gradient, without piercing the ultracentrifugation tube. During collection, the absorbance at 260 nm is read continuously to generate a polysome profile that gives a snapshot of global translational activity. Fractions are then pooled to prepare three different mRNA populations: the polysomes, mRNAs bound to several ribosomes; the monosomes, mRNAs bound to one ribosome; and mRNAs that are not bound to ribosomes. mRNAs are then extracted. This protocol has been validated for different plants and tissues including Arabidopsis thaliana seedlings and adult plants, Nicotiana benthamiana, Solanum lycopersicum, and Oryza sativa leaves.

This protocol describes an easy method to extract and fractionate transcripts from plant tissues on the basis of the number of bound ribosomes. It allows a global estimate of translation activity and the determination of the translational status of specific mRNAs.

공장 Polysom​​e 프로파일 링을위한 쉬운 방법

Translation of mRNA to protein is a fundamental and highly regulated biological process. Polysome profiling is considered as a gold standard for the ...

Analysis of the Gap Junction-dependent Transfer of miRNA with 3D-FRAP Microscopy

Small antisense RNAs, like miRNA and siRNA, play an important role in cellular physiology and pathology and, moreover, can be used as therapeutic agents in the treatment of several diseases. The development of new, innovative strategies for miRNA/siRNA therapy is based on an extensive knowledge of the underlying mechanisms. Recent data suggest that small RNAs are exchanged between cells in a gap junction-dependent manner, thereby inducing gene regulatory effects in the recipient cell. Molecular biological techniques and flow cytometric analysis are commonly used to study the intercellular exchange of miRNA. However, these methods do not provide high temporal resolution, which is necessary when studying the gap junctional flux of molecules. Therefore, to investigate the impact of miRNA/siRNA as intercellular signaling molecules, novel tools are needed that will allow for the analysis of these small RNAs at the cellular level. The present protocol describes the application of three-dimensional fluorescence recovery after photobleaching (3D-FRAP) microscopy to elucidating the gap junction-dependent exchange of miRNA molecules between cardiac cells. Importantly, this straightforward and non-invasive live-cell imaging approach allows for the visualization and quantification of the gap junctional shuttling of fluorescently labeled small RNAs in real time, with high spatio-temporal resolution. The data obtained by 3D-FRAP confirm a novel pathway of intercellular gene regulation, where small RNAs act as signaling molecules within the intercellular network.

Here, we describe the application of three-dimensional fluorescence recovery after photobleaching (3D-FRAP) for the analysis of the gap junction-dependent shuttling of miRNA. In contrast to commonly applied methods, 3D-FRAP allows for the quantification of the intercellular transfer of small RNAs in real time, with high spatio-temporal resolution.

3D-FRAP 현미경을 이용한 miRNA의 gap junction 의존적 전달 분석

Small antisense RNAs, like miRNA and siRNA, play an important role in cellular physiology and pathology and, moreover, can be used as therapeutic agents ...

In Vitro Analysis of E3 Ubiquitin Ligase Function

The covalent attachment of ubiquitin (Ub) to internal lysine residue(s) of a substrate protein, a process termed ubiquitylation, represents one of the most important post-translational modifications in eukaryotic organisms. Ubiquitylation is mediated by a sequential cascade of three enzyme classes including ubiquitin-activating enzymes (E1 enzymes), ubiquitin-conjugating enzymes (E2 enzymes), and ubiquitin ligases (E3 enzymes), and sometimes, ubiquitin-chain elongation factors (E4 enzymes). Here, in vitro protocols for ubiquitylation assays are provided, which allow the assessment of E3 ubiquitin ligase activity, the cooperation between E2-E3 pairs, and substrate selection. Cooperating E2-E3 pairs can be screened by monitoring the generation of free poly-ubiquitin chains and/or auto-ubiquitylation of the E3 ligase. Substrate ubiquitylation is defined by selective binding of the E3 ligase and can be detected by western blotting of the in vitro reaction. Furthermore, an E2~Ub discharge assay is described, which is a useful tool for the direct assessment of functional E2-E3 cooperation. Here, the E3-dependent transfer of ubiquitin is followed from the corresponding E2 enzyme onto free lysine amino acids (mimicking substrate ubiquitylation) or internal lysines of the E3 ligase itself (auto-ubiquitylation). In conclusion, three different in vitro protocols are provided that are fast and easy to perform to address E3 ligase catalytic functionality.

In Vitro Analysis of E3 Ubiquitin Ligase Function

The present study provides detailed in vitro ubiquitylation assay protocols for the analysis of E3 ubiquitin ligase catalytic activity. Recombinant proteins were expressed using prokaryotic systems such as Escherichia coli culture.

시험관 내 E3 유비퀴틴 리가제 기능 분석

The covalent attachment of ubiquitin (Ub) to internal lysine residue(s) of a substrate protein, a process termed ubiquitylation, represents one of the ...

Global Identification of Co-Translational Interaction Networks by Selective Ribosome Profiling

In recent years, it has become evident that ribosomes not only decode our mRNA but also guide the emergence of the polypeptide chain into the crowded cellular environment. Ribosomes provide the platform for spatially and kinetically controlled binding of membrane-targeting factors, modifying enzymes, and folding chaperones. Even the assembly into high-order oligomeric complexes, as well as protein-protein network formation steps, were recently discovered to be coordinated with synthesis.
Here, we describe Selective Ribosome Profiling, a method developed to capture co-translational interactions in vivo. We will detail the various affinity purification steps required for capturing ribosome-nascent-chain complexes together with co-translational interactors, as well as the mRNA extraction, size exclusion, reverse transcription, deep-sequencing, and big-data analysis steps, required to decipher co-translational interactions in near-codon resolution.

Co-translational interactions play a crucial role in nascent-chain modifications, targeting, folding, and assembly pathways. Here, we describe Selective Ribosome Profiling, a method for in vivo, direct analysis of these interactions in the model eukaryote Saccharomyces cerevisiae.

선택적 리보솜 프로파일링을 통한 공동 번역 상호 작용 네트워크의 글로벌 식별

In recent years, it has become evident that ribosomes not only decode our mRNA but also guide the emergence of the polypeptide chain into the crowded ...

Polysom​​e 프로파일에 의한 스트레스 조건에서 번역 개시 분석

Polysome 프로파일에 의한 스트레스 조건에서 번역 개시 분석