우리는 생명 과학이 작업에 자금을위한 여왕의 대학에서 예술과 과학의 학부 감사합니다. 뿐만 아니라, 우리는 필요한 시약, 장비 및 기술 지원을 제공하기 위해 턱 상 실험실을 감사드립니다. 우리는 또한 토론에 대한 그의 공헌 그는 특히 토니, QGEM 2011 감사합니다.

1. 벌레를 준비 / 세척 <ol><li> 젊은 성인 11 벌레를 동기화 할 수 있습니다. </li><li> 의 5 센티미터 주 화성의 접시에 S의 기초의 피펫 2 ㎖은 OP50 E.의 잔디를 취소 한 벌레를 개최 대장균. 웜이 버퍼에 플레이트 표면 세척하기 위해 필요한 접시를 기울이십시오. </li><li> microcentrifuge 관에 벌레-S 기초 솔루션의 피펫 1 ML. </li><li> 10 초는 6,600 rpm에서 PicoFuge를 사용하는 원심 분리기. </li><li> 그대로 벌레의 펠렛을 남겨 S의 기초를 대기음. </li><li> 벌레를 씻어 몇 번 반전, microcentrifuge 관에 1 ML S 기초 솔루션을 추가합니다. </li><li> 단계 1.4-1.6 다른 세 번 반복합니다. </li><li> 10 초 다섯 번째, 캘리포니아의 최종 볼륨에 상층 액을 흡입이 시간을 원심 분리기. 100 μL. </li><li> 각 2 μL 샘플 50 ~ 250 벌레가 보장 NGM 접시에 벌레의 피펫 2 μL. 조정S의 기초의 작은 또는 더 큰 볼륨 벌레를 현탁하여 필요에 따라 S의 기초에있는 벌레의 농도. </li><li> 즉시 1 시간에 대한 웜 세척 후 분석에 웜을 사용합니다. </li></ol> 2. 테스트 플레이트를 준비 <ol><li> 5cm 플레이트의 아래쪽에 표시 4 같은 사분면에 요리를 나눕니다. 화성 한천 또는 NGM를 사용할 수 있습니다. 3 시험의 최소 시험되는 유전자 변형 당 필요합니다. </li><li> 원점을 반경 0.5 cm (그림 1)의 원을 표시합니다. </li><li> &quot;테스트&quot;또는 사이트 기원과 서로 등거리 있는지 확인하는 &quot;C&quot; &quot;컨트롤&quot;에 대한 하나 &quot;T&quot;각 사분면에있는 점을 표시합니다. 포인트 cm 이상 떨어져 원점에서해야합니다. 테스트 사분면과 오른쪽 상단 컨트롤 등 왼쪽 아래 사분면 (그림 1)과 같이 왼쪽 상단과 오른쪽 하단 사분면을 표시합니다. </li></ol> 3. 분석을 실행 </P&gt; <ol><li> 시험 화합물 및 0.5 M 지드 (마취 사분면에 도달시 벌레를 체포하는 데 사용)의 동일한 볼륨을 결합하여 테스트 솔루션을 섞는다. 0.5 M 지드와 시험 화합물을 희석하는 데 사용되는 용매를 결합하여 제어 솔루션을 섞는다. </li><li> 원래 위에 펠렛에서 웜 용액 (1.8에서 준비) (두 선이 교차)의 피펫 2 μL. </li><li> 두 개의 &quot;T&quot;사이트 상 시험 용액의 직후, 피펫 2 μL. 마찬가지로, 두 개의 &quot;C&quot;사이트에 제어 솔루션의 동일한 금액을 피펫. </li><li> 웜 및 악취 물질 방울 한천에 흡수되고 나면, 뚜껑을 교체하고 번호판을 반전. </li><li> 60 분 후 4 ° C 배양기에서 벌레를 배치합니다. 이 계산 될 수있는 경우에만 인큐베이터에서 접시를 제거합니다. 실온에서 벌레를두면 그들을 다시 동원 할 수 있습니다. </li><li> 완전히 내부 CIRC를 넘어 각 사분면에있는 벌레의 수를 기록르. </li><li> 테스트 및 제어 사분면 모두에서 제어 솔루션을 사용하여 단계 3.2-3.6를 반복합니다. 이 컨트롤 플레이트 될 것입니다. 이러한 세 판을 제작하고 적절한 제어 역할을 실행해야합니다. </li></ol> 4. 점수 해석 / 주 화성 지수를 결정 <ol><li> 식 1을 사용하여 화성 인덱스를 계산합니다. 이 -1.0과 +1.0 사이의 화학 주성 인덱스를 얻을 것입니다. </li></ol> (1) 화성 지수 = (테스트 사분면 둘 중 웜 - 모두 제어 사분면에있는 # 웜) / (득점 웜 # 총) +1.0 점수는 대상을 향해 최대한의 매력을 나타내며 화학 대상을 포함하는 사분면에 도착 웜의 100 %를 나타냅니다. -1.0의 인덱스는 최대 반발의 증거입니다. 유사한 분석 방법은 이미 3 (표 1)을 채택하고 있습니다. <ol start="2"><li> 평균 Chemotaxi 신고의 지수 (CI)와 표준 오차 (SEM) 의미합니다. 학생의 T-테스트는 테스트 및 컨트롤 플레이트에서 데이터를 비교 수행합니다. </li></ol>

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우리는 공개 아무것도 없어.

화성은 신경 및 세포 메커니즘의 복잡한 집합에 의해 제어하지만, 쉽게 객관적으로 화성 분석을 사용하여 정량화 할 수있다. 분석에서 최상의 결과를 얻으려면, 중요한 특정 단계를 수행해야합니다. 첫째, 벌레를 준비하는 것은 일관성있는 실험 결과를 산출 필수적이다. 서로 다른 삶의 단계에서 웜 다르게 13 동작, 그래서 혼합 단계 웜 왜곡 될 실험 결과. 둘째, 모든 E. 보장 잔류 ?...

워드는 첫 번째 1973 5 화성 분석을 개발하고, 그 이후 지금까지 도달하는 응용 프로그램을 가지고 있습니다. 신경 생물학은 화성 분석의 다양한 사용의 혜택을있는 하나의 필드입니다. 후각 적응, 학습과 기억의 간단한 형태는 C로 입증되었습니다 화성 분석하기 6을 사용 엘레 간스. 그들은 또한 표시하는 데 사용되었는지 C. 엘레 에탄올 벌레의 행동 가소성을 보여줍니다뿐만 아니라 허용 오차 결과를 개발할 수 있지만, 또한 벌레가 인간 3 알코올 의존의 연구에 매우 유용 할 수 있음을 보여줍니다. 분석 심지어 C의 능력을 입증하기 위해 개발되었습니다 엘레은 협회가 chemoattractants과 음식 (OP50) 7 사이의 웜에 의해 만들어진 것을 보여 단기 및 장기 기억 저장합니다. 또한 C.에 대한 현재 사용 가능한 광범위한 정보를 제공 elegans의 게놈 chemotaxiC. s의 동작 엘레은 돌연변이에게 1,8를 유도하여 여러 번 변경되었습니다. 여기에는 C의 개발과 같은 많은 흥미로운 기술의 가능성에 대한 수 생물학적 도구로 엘레 간스. 따라서, 1973 년 화성 분석의 초기 개발 이후, 그것은 자주 변경하고 다양한 분야의 신비를 해명하는 데 사용되었습니다. 일부 분석은 목표를 향해 웜에 의해 수행되는 특정 경로를 발견하는 것을 목표. 이런 종류의 원형 분석은 구청 5에 의해 개발되었다. 세 가지 웜은 15 분 동안 녹인 한천에 배치했다. 그들의 움직임들은 판의 중앙에 유인에 그라데이션까지 접시의 주변에서 여행으로 그들이 떠난 인장으로 추적했다. 접시에 모든 벌레는 각 재판의 끝에서 클로로포름을 사용하여 체포되었다. 이 방법의 한 자손은 유인하고 컨트롤과 접시의 중간에 하나 벌레를 배치기원 2에서 t 같고 반대 거리. 피어스 - 시모무라 하였다. 화성 9에 관련된 운동의 정확한 특성을 관찰하는 분석을 개발했다. 개별 웜은 유인의 소스에 culminating, 9cm 페트리 접시 유인 또는 방사형 모양의 그라데이션의 균일 한 농도를 포함하는 하나에 배치되었다. 벌레를 인식하는 컴퓨터 소프트웨어 프로그램은 관찰 된 행동을 기록하는 데 사용되었다. 현미경에 부착 된 비디오 카메라는 분석이 웜이 시야에 남아 보장하기 위해 실행 자동으로 페트리 접시를 조정하는 단계와 함께했다. 이것으로부터,보다 자세한 정보는 C.에 의해 표시되는 피 루엣의 원인에 관한 발견 엘레 간스. 여기에 설명 된 하나 이상의 유사한 다른 분석은 시험 물질에 웜의 큰 인구의 응답을 테스트했습니다. 두 사분면 화성 분석 실험했습니다다양한 신경, 수용체 및 신호 전달 분자가 때 C를 연주하는 역할을 탐구하는 데 사용 엘레은 다양한 화합물의 1에 노출되었다. 20-50 사이의 세척 웜 마취, 나트륨 아 지드 (NaN의 3)과 함께 극 끝에서 유인 및 제어 플레이트의 중앙 근처에 배치되었다. 60 분 후, -1.0에서 +1.0 사이의 값을 가진 화성 인덱스 유인 나 컨트롤에 부착 된 얼마나 많은 벌레의 차이에 따라 생성되었습니다. 이전의 분석은 엄격하게 비 운동성이 웜을 평가하는 데 실패하더라도 유사한 화학 주성 인덱스는이 문서에서보고 된 분석에 사용되었다. 이 분석은 다음 추가 화성에 신경 절제의 효과를 시험에 적용되었다. 100-200 벌레는 네 개의 사분면 3를 포함하는 접시의 중앙에 배치 된 위치를 앞서 언급 한 분석의 또 다른 변형이 수행되었다. 인접 사분면은 하나 또는 시험을 포함물질을 제어 할 수 있습니다. 이전 분석에서와 같이, 웜 득점되기 전에 지드 화 나트륨의 작용에 의해 고정되었다. 유사한 방법은 C.의 반응을 평가하는 방법으로 여기에 설명되어 있습니다 다양한 화합물 엘레 간스. 그러나 아래의 방법은 움직 웜 휴대 분리 임계 거리를 통과 한 웜을 평가 이점이 있습니다. 다른 분석은 움직 벌레를 무시 유사 지침을 통합했다. Frøkjær-젠슨 하였다. 휘발성과 물을 모두 수용성 화합물이 10을 테스트하는 데 사용할 수있는 다양한 분석을 개발했다. 페트리 접시는 네 개의 사분면으로 분할되었다. 상단과 하단 사분면 용제를 포함하지 않았다. 왼쪽 사분면 물을 포함하고, 오른쪽 유인이 포함되어 있습니다. 수용성 화합물은 AGA에 직접 배치 된 반면, 휘발성 악취를 테스트 할 때, 분석이 적절한 사분면을 통해, 접시의 뚜껑에 배치 된R. C.의 화학 주성 반응을 평가하기위한 현재 존재 방법 엘레은 지속적으로 사용, 효율성 및 정확성의 용이성을 최적화하기 위해 세련되고있다. 여기에 설명 된 분석이 웜의 가장 큰 수 (. 최대 처리량 : 250 웜 / 판 시간당, Lee 등 3에 의해 입증 처리량보다 약간 큰) 평가의 기능을 가지고있는 동안 따라서,이 방법의 진짜 힘은 이전 분석 (표 1)의 여러 속성의 간결한 절정.

<table border="1">
 <tbody>
 <tr>
 <td>Name of Reagent/Material</td>
 <td>Company</td>
 <td>Catalogue Number</td>
 <td>Comments</td>
 </tr>
 <tr>
 <td>S Basal (- cholesterol) [5.8 g NaCl; 1 M K phosphate buffer, pH 6.0; dH2O to 1 liter.] Autoclave</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>PicoFuge</td>
 <td>Stratagene</td>
 <td>400552</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Microscopes</td>
 <td>Leica</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Dissecting</td>
 <td>Leica</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>P1000 Pipette</td>
 <td>Gilson</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>P10 Pipette</td>
 <td>Gilson</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>0.5 M Sodium Azide</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Chemotaxis Agar [1.6% BBL-agar (Benton-Dickinson) or 2% Difco-agar. Autoclave. Add 5 mM potassium phosphate, pH 6.0; 1 mM CaCl2, 1 mM MgSO4]</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Ethanol/Distilled Water</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Test Compounds (eg. 0.5% diacetyl)</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Agar</td>
 <td>Bio-Rad</td>
 <td>166-0600</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>NH4Cl</td>
 <td>Amresco</td>
 <td>CA97062-046</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>MOPS</td>
 <td>VWR</td>
 <td>CA12001-120</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>NH4OH</td>
 <td>BDH</td>
 <td>CABDH8641-2</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>0.25% Tween 20</td>
 <td>Bio-Rad</td>
 <td>170-6531</td>
 <td>&nbsp;</td>
 </tr>
 </tbody>
</table>

c. elegans chemotaxis assay

많은 생물 화성은 음식 근원을 추구 유해 물질을 피하고, 짝을 찾기 위해 사용합니다. Caenorhabditis의 엘레 인상적 화성 동작이 있습니다. 악취 물질에 웜의 반응을 테스트 뒤에 전제는 지역에 배치하고 악취 물질에 대한 응답으로 유발의 움직임을 관찰하는 것입니다. 도 사용할 수있는 많은 분석과 함께, 중요한 샘플 크기를 유지하면서 서로 웜의 상호 작용을 최소화하면서, 제어 및 시험 영역 모두에 상대적인 시작 위치 웜 최적화가 진행 1-10 작업 남아있다. 여기에 설명 된 방법은 Bargmann 등 1.에 의해 개발 된 분석을 수정하여 이러한 문제를 해결하는 것을 목표로하고있다. 페트리 접시는 네 개의 사분면으로 나누어 져 있습니다, &quot;테스트&quot;두 표시된 두 개의 반대 사분면은 &quot;컨트롤&quot;을 지정합니다. 마취는 모든 테스트 및 제어 장소에 배치됩니다. 웜 circl와 접시의 중앙에 배치됩니다E는 비 운동성이 웜은 무시 될 수 있도록하기 위해 원점을 표시했다. 4 - 쿼드런트 시스템을 활용하여보다 한 2 개의 1에 관계없이 시작 원산지 어느 쪽의, 그들은 테스트 및 컨트롤 샘플에서 등거리로 웜의 움직임에 편견을 제거합니다. 이 웜을 지연 시키거나 그들의 의도 된 경로의 잘못된 해석을 항복, 더 우회 길을하도록 할 수 있습니다 악취 물질에 응답하기 위해 다른 웜의 클러스터를 통해 여행 강제 웜의 문제를 우회. 또한이 방법은 큰 샘플 크기를 가지고 있으며 연구원 무인 분석을 실행하고 할당 된 시간이 만료되면 웜 점수를함으로써 실질적인 이점을 보여줍니다.

야생형 (N2) C. 비교 ODR-10 (KY10) 돌연변이로 엘레 간스. 우리는 알려진 C를 디 아세틸 사용 엘레은 화학 주성, 디 아세틸 1,12에 대한 수용체를 부족 돌연변이의에 야생형 벌레를 비교. 야생형 (N2) 웜에 대한 화학 주성 지수는 에탄올 및 0.839-0.100 ± 0.066이었다 ± 0.031-0.5 % 디 아세틸. 예상대로, 디 아세틸은 야생 형 웜 (P &lt;0.003)에서 유의 한 ch...

Watch this Scientific Journal Video about C. elegans Chemotaxis Assay at JoVE.com

C. elegans Chemotaxis Assay

정량의 화학 주성 반응을 평가하는 방법<em&gt; Caenorhabditis의 엘레</em&gt;이 설명되어 있습니다. 화성 지수 (CI)가 정확하게 특정 대상에 웜의 반응을 평가하고, 균주 및 그 화합물의 비교의 플랫폼으로 제공하는 방법으로 사용 하였다.

C. elegans의 주 화성 분석

Many organisms use chemotaxis to seek out food sources, avoid noxious substances, and find mates.  Caenorhabditis elegans has impressive chemotaxis ...

Research

JoVE Journal

Biology

C. elegans Chemotaxis Assay

45.0K 조회수.  Queen's University. 정량의 화학 주성 반응을 평가하는 방법 Caenorhabditis의 엘레이 설명되어 있습니다. 화성 지수 (CI)가 정확하게 특정 대상에 웜의 반응을 평가하고, 균주 및 그 화합물의 비교의 플랫폼으로 제공하는 방법으로 사용 하였다.

비디오: C. elegans Chemotaxis Assay

Generation of Stable Transgenic C. elegans Using Microinjection

Transgenic Caenorhabditis elegans can be readily created via microinjection of a DNA plasmid solution into the gonad 1. The plasmid DNA rearranges to form extrachromosomal concatamers that are stably inherited, though not with the same efficiency as actual chromosomes 2. A gene of interest is co-injected with an obvious phenotypic marker, such as rol-6 or GFP, to allow selection of transgenic animals under a dissecting microscope. The exogenous gene may be expressed from its native promoter for cellular localization studies. Alternatively, the transgene can be driven by a different tissue-specific promoter to assess the role of the gene product in that particular cell or tissue. This technique efficiently drives gene expression in all tissues of C. elegans except for the germline or early embryo 3. Creation of transgenic animals is widely utilized for a range of experimental paradigms. This video demonstrates the microinjection procedure to generate transgenic worms. Furthermore, selection and maintenance of stable transgenic C. elegans lines is described.

This video demonstrates the technique of microinjection into the gonad of C. elegans to create transgenic animals.

Microinjection을 사용하여 안정적인 트렌스​​ 제닉 C. 엘레간스의 생성

Transgenic Caenorhabditis elegans can be readily created via microinjection of a DNA plasmid solution into the gonad 1.  The plasmid DNA rearranges to ...

연구

생물학

Application of a C. elegans Dopamine Neuron Degeneration Assay for the Validation of Potential Parkinson's Disease Genes

Improvements to the diagnosis and treatment of Parkinson's disease (PD) are dependent upon knowledge about susceptibility factors that render populations at risk. In the process of attempting to identify novel genetic factors associated with PD, scientists have generated many lists of candidate genes, polymorphisms, and proteins that represent important advances, but these leads remain mechanistically undefined. Our work is aimed toward significantly narrowing such lists by exploiting the advantages of a simple animal model system. While humans have billions of neurons, the microscopic roundworm Caenorhabditis elegans has precisely 302, of which only eight produce dopamine (DA) in hemaphrodites. Expression of a human gene encoding the PD-associated protein, alpha-synuclein, in C. elegans DA neurons results in dosage and age-dependent neurodegeneration.
Worms expressing human alpha-synuclein in DA neurons are isogenic and express both GFP and human alpha-synuclein under the DA transporter promoter (Pdat-1). The presence of GFP serves as a readily visualized marker for following DA neurodegeneration in these animals. We initially demonstrated that alpha-synuclein-induced DA neurodegeneration could be rescued in these animals by torsinA, a protein with molecular chaperone activity 1. Further, candidate PD-related genes identified in our lab via large-scale RNAi screening efforts using an alpha-synuclein misfolding assay were then over-expressed in C. elegans DA neurons. We determined that five of seven genes tested represented significant candidate modulators of PD as they rescued alpha-synuclein-induced DA neurodegeneration 2. Additionally, the Lindquist Lab (this issue of JoVE) has performed yeast screens whereby alpha-synuclein-dependent toxicity is used as a readout for genes that can enhance or suppress cytotoxicity. We subsequently examined the yeast candidate genes in our C. elegans alpha-synuclein-induced neurodegeneration assay and successfully validated many of these targets 3, 4.
Our methodology involves generation of a C. elegans DA neuron-specific expression vector using recombinational cloning of candidate gene cDNAs under control of the Pdat-1 promoter. These plasmids are then microinjected in wild-type (N2) worms, along with a selectable marker for successful transformation. Multiple stable transgenic lines producing the candidate protein in DA neurons are obtained and then independently crossed into the alpha-synuclein degenerative strain and assessed for neurodegeneration, at both the animal and individual neuron level, over the course of aging.

Application of a C. elegans Dopamine Neuron Degeneration Assay for the Validation of Potential Parkinson&#039;s Disease Genes

This video demonstrates how to use C. elegans to assess dopaminergic neuron neurodegeneration as a model for Parkinson's disease. Furthermore, genetic screens are used to identify factors that either enhance degeneration or are neuroprotective.

잠재적인 파킨슨병의 유전자 검증을위한 C. 엘레간스 도파민 신경 세포의 변성 분석의 응용

Improvements to the diagnosis and treatment of Parkinson's disease (PD) are dependent upon knowledge about susceptibility factors that render populations ...

Paradigms for Pharmacological Characterization of C. elegans Synaptic Transmission Mutants

The nematode, Caenorhabditis elegans, has become an expedient model for studying neurotransmission. C. elegans is unique among animal models, as the anatomy and connectivity of its nervous system has been determined from electron micrographs and refined by pharmacological assays. In this video, we describe how two complementary neural stimulants, an acetylcholinesterase inhibitor, called aldicarb, and a gamma-aminobutyric acid (GABA) receptor antagonist, called pentylenetetrazole (PTZ), may be employed to specifically characterize signaling at C. elegans neuromuscular junctions (NMJs) and facilitate our understanding of antagonistic neural circuits.
Of 302 C. elegans neurons, nineteen GABAergic D-type motor neurons innervate body wall muscles (BWMs), while four GABAergic neurons, called RMEs, innervate head muscles. Conversely, thirty-nine motor neurons express the excitatory neurotransmitter, acetylcholine (ACh), and antagonize GABA transmission at BWMs to coordinate locomotion. The antagonistic nature of GABAergic and cholinergic motor neurons at body wall NMJs was initially determined by laser ablation and later buttressed by aldicarb exposure. Acute aldicarb exposure results in a time-course or dose-responsive paralysis in wild-type worms. Yet, loss of excitatory ACh transmission confers resistance to aldicarb, as less ACh accumulates at worm NMJs, leading to less stimulation of BWMs. Resistance to aldicarb may be observed with ACh-specific or general synaptic function mutants. Consistent with antagonistic GABA and ACh transmission, loss of GABA transmission, or a failure to negatively regulate ACh release, confers hypersensitivity to aldicarb. Although aldicarb exposure has led to the isolation of numerous worm homologs of neurotransmission genes, aldicarb exposure alone cannot efficiently determine prevailing roles for genes and pathways in specific C. elegans motor neurons. For this purpose, we have introduced a complementary experimental approach, which uses PTZ.
Neurotransmission mutants display clear phenotypes, distinct from aldicarb-induced paralysis, in response to PTZ. Wild-type worms, as well as mutants with specific inabilities to release or receive ACh, do not show apparent sensitivity to PTZ. However, GABA mutants, as well as general synaptic function mutants, display anterior convulsions in a time-course or dose-responsive manner. Mutants that cannot negatively regulate general neurotransmitter release and, thus, secrete excessive amounts of ACh onto BWMs, become paralyzed on PTZ. The PTZ-induced phenotypes of discrete mutant classes indicate that a complementary approach with aldicarb and PTZ exposure paradigms in C. elegans may accelerate our understanding of neurotransmission. Moreover, videos demonstrating how we perform pharmacological assays should establish consistent methods for C. elegans research.

This video demonstrates how to employ two neural stimulants, aldicarb and pentylenetetrazole (PTZ), in complementary ways to study synaptic function in the nematode, C. elegans. This complementary approach may also be used to shed light on evolutionarily conserved mechanisms for modulating neuronal synchrony and has implications for epilepsy and seizures.

C. 엘레간스 시냅틱 전송 돌연변이의 약리 특성에 대한 패러다임

The nematode, Caenorhabditis elegans, has become an expedient model for studying neurotransmission. C. elegans is unique among animal models, as the ...

Dissecting and Recording from The C. Elegans Neuromuscular Junction

Neurotransmission is the process by which neurons transfer information via chemical signals to their post-synaptic targets, on a rapid time scale. This complex process requires the coordinated activity of many pre- and post-synaptic proteins to ensure appropriate synaptic connectivity, conduction of electrical signals, targeting and priming of secretory vesicles, calcium sensing, vesicle fusion, localization and function of postsynaptic receptors and finally, recycling mechanisms. As neuroscientists it is our goal to elucidate which proteins function in each of these steps and understand their mechanisms of action. Electrophysiological recordings from synapses provide a quantifiable read out of the underlying electrical events that occur during synaptic transmission. By combining this technique with the powerful array of molecular and genetic tools available to manipulate synaptic proteins in C. elegans, we can analyze the resulting functional changes in synaptic transmission. 
The C. elegans NMJs formed between motor neurons and body wall muscles control locomotion, therefore, mutants with uncoordinated locomotory phenotypes (known as unc s) often perturb synaptic transmission at these synapses 1. Since unc mutants are maintained on a rich supply of a bacterial food source, they remain viable as long as they retain some pharyngeal pumping ability to ingest food. This, together with the fact that C. elegans exist as hermaphrodites, allows them to pass on mutant progeny without the need for elaborate mating behaviors. These attributes, coupled with our recent ability to record from the worms NMJs 2,3,7 make this an excellent model organism in which to address precisely how unc mutants impact neurotransmission. 
The dissection method involves immobilizing adult worms using a cyanoacrylic glue in order to make an incision in the worm cuticle exposing the NMJs. Since C. elegans adults are only 1 mm in length the dissection is performed with the use of a dissecting microscope and requires excellent hand-eye coordination. NMJ recordings are made by whole-cell voltage clamping individual body wall muscle cells and neurotransmitter release can be evoked using a variety of stimulation protocols including electrical stimulation, light-activated channel-rhodopsin-mediated depolarization 4 and hyperosmotic saline, all of which will be briefly described.

Application of electrophysiology to accessible synapses provides a quantifiable measure of synaptic activity, useful in analyzing synaptic mutants. This article describes a dissection method used to expose the neuromuscular junctions (NMJ) of Caenorhabditis elegans (C. elegans) and briefly discusses some of the uses to which this preparation can be applied.

해부 및 C. 엘레간스 신경근육학 융티온에서 레코딩

Neurotransmission is the process by which neurons transfer information via chemical signals to their post-synaptic targets, on a rapid time scale.   This ...

Generation of Transgenic C. elegans by Biolistic Transformation

The number of laboratories using the free living nematode C. elegans is rapidly growing. The popularity of this biological model is attributed to a rapid generation time and short life span, easy and inexpensive maintenance, fully sequenced genome, and array of RNAi resources and mutant animals. Additionally, analysis of the C. elegans genome revealed a great similarity between worms and higher vertebrates, which suggests that research in worms could be an important adjunct to studies performed in whole mice or cultured cells. A powerful and important part of worm research is the ability to use transgenic animals to study gene localization and function. Transgenic animals can be created either via microinjection of the worm germline or through the use of biolistic bombardment. Bombardment is a newer technique and is less familiar to a number of labs. Here we describe a simple protocol to generate transgenic worms by biolistic bombardment with gold particles using the Bio-Rad PDS-1000 system. Compared with DNA microinjection into hermaphrodite germline, this protocol has the advantage of not requiring special skills from the operator with regards to identifying worm anatomy or performing microinjection. Further multiple transgenic lines are usually obtained from a single bombardment. Also in contrast to microinjection, biolistic bombardment produces transgenic animals with both extrachromosomal arrays and integrated transgenes. The ability to obtain integrated transgenic lines can avoid the use of mutagenic protocols to integrate foreign DNA. In conclusion, biolistic bombardment can be an attractive method for the generation of transgenic animals, especially for investigators not interested in investing the time and effort needed to become skilled at microinjection.

Generation of Transgenic C. elegans by Biolistic Transformation

Transgenic worms are commonly used in C. elegans research. Described is a simple, yet effective, protocol to introduce transgenes into worms using biolistic bombardment with DNA-coated gold particles. The effort involved and results of bombardment compare favorably with microinjection for the generation of transgenic animals.

트렌스 제닉의 생성 C. 엘레간스 Biolistic 변환에 의해

The number of laboratories using the free living nematode C. elegans is rapidly growing. The popularity of this biological model is attributed to a rapid ...

RNAi Screening to Identify Postembryonic Phenotypes in C. elegans

C. elegans has proven to be a valuable model system for the discovery and functional characterization of many genes and gene pathways1. More sophisticated tools and resources for studies in this system are facilitating continued discovery of genes with more subtle phenotypes or roles. 
Here we present a generalized protocol we adapted for identifying C. elegans genes with postembryonic phenotypes of interest using RNAi2. This procedure is easily modified to assay the phenotype of choice, whether by light or fluorescence optics on a dissecting or compound microscope. This screening protocol capitalizes on the physical assets of the organism and molecular tools the C. elegans research community has produced. As an example, we demonstrate the use of an integrated transgene that expresses a fluorescent product in an RNAi screen to identify genes required for the normal localization of this product in late stage larvae and adults. First, we used a commercially available genomic RNAi library with full-length cDNA inserts. This library facilitates the rapid identification of multiple candidates by RNAi reduction of the candidate gene product. Second, we generated an integrated transgene that expresses our fluorecently tagged protein of interest in an RNAi-sensitive background. Third, by exposing hatched animals to RNAi, this screen permits identification of gene products that have a vital embryonic role that would otherwise mask a post-embryonic role in regulating the protein of interest. Lastly, this screen uses a compound microscope equipped for single cell resolution.

RNAi Screening to Identify Postembryonic Phenotypes in C. elegans

We describe a sensitized method to identify postembryonic regulators of protein expression and localization in C. elegans using an RNAi-based genomic screen and an integrated transgene that expresses a functional, fluorescently tagged protein.

에 Postembryonic Phenotypes을 식별하기 위해 RNAi 심사 C. elegans</em

C. elegans has proven to be a valuable model system for the discovery and functional characterization of many genes and gene pathways1. More sophisticated ...

Basic Caenorhabditis elegans Methods: Synchronization and Observation

Research into the molecular and developmental biology of the nematode Caenorhabditis elegans was begun in the early seventies by Sydney Brenner and it has since been used extensively as a model organism 1. C. elegans possesses key attributes such as simplicity, transparency and short life cycle that have made it a suitable experimental system for fundamental biological studies for many years 2. Discoveries in this nematode have broad implications because many cellular and molecular processes that control animal development are evolutionary conserved 3.
C. elegans life cycle goes through an embryonic stage and four larval stages before animals reach adulthood. Development can take 2 to 4 days depending on the temperature. In each of the stages several characteristic traits can be observed. The knowledge of its complete cell lineage 4,5 together with the deep annotation of its genome turn this nematode into a great model in fields as diverse as the neurobiology 6, aging 7,8, stem cell biology 9 and germ line biology 10. 
An additional feature that makes C. elegans an attractive model to work with is the possibility of obtaining populations of worms synchronized at a specific stage through a relatively easy protocol. The ease of maintaining and propagating this nematode added to the possibility of synchronization provide a powerful tool to obtain large amounts of worms, which can be used for a wide variety of small or high-throughput experiments such as RNAi screens, microarrays, massive sequencing, immunoblot or in situ hybridization, among others. 
Because of its transparency, C. elegans structures can be distinguished under the microscope using Differential Interference Contrast microscopy, also known as Nomarski microscopy. The use of a fluorescent DNA binder, DAPI (4',6-diamidino-2-phenylindole), for instance, can lead to the specific identification and localization of individual cells, as well as subcellular structures/defects associated to them.

Basic Caenorhabditis elegans Methods: Synchronization and Observation

The easiness of maintaining and propagating the nematode C. elegans make it a nice model organism to work with. The possibility of synchronizing worms allows the work with a significant amount of subjects at the same developmental stage, what facilitates the study of one particular process in many animals.

기본<em&gt; Caenorhabditis elegans</em&gt; 방법 : 동기화 및 전망

Research into the molecular and developmental biology of the nematode Caenorhabditis elegans was begun in the early seventies by Sydney Brenner and it has ...

A Method for Culturing Embryonic C. elegans Cells

C. elegans is a powerful model system, in which genetic and molecular techniques are easily applicable. Until recently though, techniques that require direct access to cells and isolation of specific cell types, could not be applied in C. elegans. This limitation was due to the fact that tissues are confined within a pressurized cuticle which is not easily digested by treatment with enzymes and/or detergents. Based on early pioneer work by Laird Bloom, Christensen and colleagues 1 developed a robust method for culturing C. elegans embryonic cells in large scale. Eggs are isolated from gravid adults by treatment with bleach/NaOH and subsequently treated with chitinase to remove the eggshells. Embryonic cells are then dissociated by manual pipetting and plated onto substrate-covered glass in serum-enriched media. Within 24 hr of isolation cells begin to differentiate by changing morphology and by expressing cell specific markers. C. elegans cells cultured using this method survive for up 2 weeks in vitro and have been used for electrophysiological, immunochemical, and imaging analyses as well as they have been sorted and used for microarray profiling.

A Method for Culturing Embryonic C. elegans Cells

We describe here a revised protocol for large-scale culture of embryonic C. elegans cells. Embryonic C. elegans cells cultured in vitro using this method, appear to differentiate and recapitulate the expression of genes in a cell specific manner. Techniques that require direct access to the cells or isolation of specific cell types from the other tissues can be applied on C. elegans cultured cells.

배아 배양하는 방법<em&gt; C. 엘레</em&gt; 셀

C. elegans is a powerful model system, in which genetic and molecular techniques are easily applicable. Until recently though, techniques that require ...

Antibody Staining in C. Elegans Using &quot;Freeze-Cracking&quot;

To stain C. elegans with antibodies, the relatively impermeable cuticle must be bypassed by chemical or mechanical methods. "Freeze-cracking" is one method used to physically pull the cuticle from nematodes by compressing nematodes between two adherent slides, freezing them, and pulling the slides apart. Freeze-cracking provides a simple and rapid way to gain access to the tissues without chemical treatment and can be used with a variety of fixatives. However, it leads to the loss of many of the specimens and the required compression mechanically distorts the sample. Practice is required to maximize recovery of samples with good morphology. Freeze-cracking can be optimized for specific fixation conditions, recovery of samples, or low non-specific staining, but not for all parameters at once. For antibodies that require very hard fixation conditions and tolerate the chemical treatments needed to chemically permeabilize the cuticle, treatment of intact nematodes in solution may be preferred. If the antibody requires a lighter fix or if the optimum fixation conditions are unknown, freeze-cracking provides a very useful way to rapidly assay the antibody and can yield specific subcellular and cellular localization information for the antigen of interest.

Antibody Staining in C. Elegans Using &quot;Freeze-Cracking&quot;

"Freeze-cracking," a method for exposing the inner tissues of the nematode C. elegans to antibodies for protein localization, is demonstrated.

항체 염색법에<em&gt; C. 엘레</em&gt; &quot;동결 크래킹 사용&quot;

To stain C.  elegans with antibodies, the relatively impermeable cuticle must be  bypassed by chemical or mechanical methods.  "Freeze-cracking" is one ...

Measuring the Effects of Bacteria on C. Elegans Behavior Using an Egg Retention Assay

C. elegans egg-laying behavior is affected by environmental cues such as osmolarity1 and vibration2. In the total absence of food C. elegans also cease egg-laying and retain fertilized eggs in their uterus3. However, the effect of different sources of food, especially pathogenic bacteria and particularly Enterococcus faecalis, on egg-laying
	behavior is not well characterized. The egg-in-worm (EIW) assay is a useful tool to quantify the effects of different types of bacteria, in this case E. faecalis, on egg- laying behavior.
	
	EIW assays involve counting the number of eggs retained in the uterus of C. elegans4. The EIW assay involves bleaching staged, gravid adult C. elegans to remove the cuticle and separate the retained eggs from the animal. Prior to bleaching, worms are exposed to bacteria (or any type of environmental cue) for a fixed period of time. After bleaching, one is very easily able to count the number of eggs retained inside the uterus of the worms. In this assay, a quantifiable increase in egg retention after E. faecalis exposure can be easily measured. The EIW assay is a behavioral assay that may be used to screen for potentially pathogenic bacteria or the presence of environmental toxins. In addition, the EIW assay may be a tool to screen for drugs that affect neurotransmitter signaling since egg-laying behavior is modulated by neurotransmitters such as serotonin and acetylcholine5-9.

Measuring the Effects of Bacteria on C. Elegans Behavior Using an Egg Retention Assay

An egg-in-worm (EIW) assay is a useful method to quantify egg-laying behavior. Alterations in egg laying can be a behavioral response of the model organism Caenorhabditis elegans to potentially harmful environmental substances such as those produced by pathogenic bacteria.

에 박테리아의 효과를 측정<em&gt; C. 엘레</em계란 보존 분석을 사용하여&gt; 행동

C. elegans egg-laying behavior is  affected by environmental cues such as osmolarity1 and  vibration2. In the total absence of food C. elegans also cease ...