We gratefully thank the DFG for financial support (HO 1779/21-1) as well as Katrin Kumke and Dr. Veit Schubert (IPK, Gatersleben) for technical advice.

1. 염색체 준비 <ol><li> 종자 발아 및 뿌리 끝의 고정 <ol><li> 22 ~ 24 ℃에서 2 일간 어두운 조건에서 배양 접시에 촉촉한 필터 종이의 두 층에 10 ~ 20 보리 씨앗을 발아. 면도날을 사용하여 시드로부터 1-2cm의 길이 격렬한 뿌리 잘라. </li><li> 분쇄 된 얼음 - 물에 차가운 수돗물을 함유하는 500 ㎖의 유리 병을 배치하여 빙 냉수를 준비한다. 빙 냉수를 폭기 및 중기 세포의 빈도를 증가시키기 위해 20 시간 동안 뿌리 끝 부분을 넣는다. </li><li> 50ml의 에탄올에 물을 뿌리 전송 : 아세트산 (3 : 1)을 고정 제 2 일 동안 실온에서이를 해결하기 위해. 갓 준비 에탄올에 보관 뿌리 : 아세트산 (3 : 1) 4 ° C에서 정착 년까지 사용할까지. </li></ol></li><li> 세탁 효소 처리 <ol><li> 5 분 50 회 mL 유리 비커를 사용하여 30 mL의 얼음처럼 차가운 수돗물로 씻어 뿌리 10-20. 쌍안 현미경을 사용합니다. 에 의해 뿌리 하나를 전송30 mL의 0.01 M 시트 레이트 완충액 (+ 0.01 M 시트르산 나트륨, 0.01 M 시트르산, pH를 4.8) 겸자를 사용하여 5 분 동안 두번 유리 비커를 흔들어 씻는다. 완전히 액체를 제거하고 차단 원하지 않는 비 분열 조직을 면도날을 사용하여 필터 종이에 뿌리를 놓습니다. </li><li> 시계 접시로 식물 조직을 부드럽게 약 50 분 (표 1), 37 ° C에서 1 ㎖의 효소 혼합물에 20 뿌리 끝까지 배양한다. 효소 혼합물 0.01 M 구연산 버퍼에 희석 0.7 % 셀룰라아제 R10, 0.7 %의 셀룰라아제, 1 % pectolyase과 1 % cytohelicase가 포함되어 있습니다. -20 ℃에서 효소 혼합물을 저장하고 다섯 번까지 재사용. </li><li> 피펫으로 효소를 제거하고 잔류 효소를 대체하기 위해 두 번 5 ml의 0.01 M 구연산 버퍼와 얼음에 뿌리 끝을 씻는다. </li></ol></li><li> 루트 침용 <ol><li> 두 번주의 깊게 같은 시계 접시에 1 ml의 96 % 에탄올로 세척 루트 팁. 갓 준비 고정액 (25 % 에탄올 75 % 아세트산)와 에탄올을 교체합니다. 10 ~ 15를 사용하여루트 팁 당 μL 정착. </li><li> 해부 바늘이나 집게로 2 ML 튜브에 정착와 함께 전송 루트 팁과 분해 루트 분열 조직. 세포 현탁액을 얻기 위해 세포를 다시 중단 튜브 20 번 눌러. 2 개월 -20 ° C 최대의 세포 현탁액을 저장합니다. </li></ol></li><li> 세포 현탁액의 적하 <ol><li> 50 ° C에서 뜨거운 접시에 물을 적신 종이 조직의 2 ~ 3 층을 놓습니다. 30 분 동안 냉장고에 얼음처럼 차가운 수돗물에 현미경 슬라이드를 담가. 장소는 축축한 종이 티슈 위에 슬라이드. </li><li> 피펫 7-10 세포 현탁액의 μL와 핫 플레이트에 배치 된 냉각 슬라이드에 20cm의 거리에서 드롭합니다. 피펫 (10) 슬라이드에 세포 현탁액과 같은 장소에 아세트산 - 에탄올 혼합물의 μL 및 추가 2 분 동안 핫 플레이트에 슬라이드를 유지. 물티슈없이 핫 플레이트에 슬라이드를 배치하고 1 분 동안 건조 할 수 있습니다. </li></ol></li><li> 품질 관리 및 스토리지 박슬라이드의 전자 <ol><li> 염색체 스프레드의 품질을 제어하는​​ 위상차 현미경을 사용하여 슬라이드를 확인한다. -20 ° C에서 코 플린 항아리에 96 %의 에탄올에 침지하여 같은 날 또는 저장 중 슬라이드를 사용합니다. </li></ol></li><li> 물고기 전에 슬라이드 전처리; 모든 단계는 실온에서 수행 <ol><li> 배 SSC의 50 ㎖를 포함하는 코 플린 항아리에 넣어 슬라이드 5 분 (20 배 SSC는 3 M의 NaCl 300 MM의 트리 소듐 시트 레이트를 포함). 3-10 분 동안 45 % 아세트산 50 ㎖를 함유하는 코 플린 항아리 집게, 이전 슬라이드를 사용. </li><li> 전달은 10 분 동안 2 배 SSC 50 ㎖를 함유하는 코 플린 항아리에 슬라이드. 10 분 동안 (2 × SSC)에 4 % 포름 알데히드의 50 ㎖를 포함하는 코 플린 항아리로 전송 슬라이드 빠져들게 슬라이드 염색체를 해결하려면. </li><li> 50 ml의 2 배 SSC를 포함하는 코 플린 항아리, 4 분 각각의 슬라이드 3 회 세척하여 포름 알데히드를 제거합니다. 수직에서 70 %의 시리즈에서 2 분, 90 %, 100 % 에탄올, 각각 건조 슬라이드의 코 플린 항아리에 슬라이드를 탈수위치. </li></ol></li></ol> 제자리 하이브리드 2. 형광 (물고기) <ol><li> 각 슬라이드에 대해, 탈 포름 아미드 10 μL, 4X 혼성화 완충액 5 μL를 사용하여 총 20 μL의 혼성화 용액을 제조 하였다 (200 ㎕를 완충액 80 ㎕의 20 배 SSC, 8 ㎕의 1 M 트리스 -HCl pH가 8.0를 포함 1.6 ㎕의 0.5 M EDTA, 11.2 μL 10 μg의 / μL 연어 정자와 99.2 μL의 DNase를없는 물), 프로브의 3 μL와 DNase를없는 물 2 μL. </li><li> 24 X 32mm 커버 슬립과 슬라이드 커버 당 혼성화 용액 20 μl를 추가하고 고무 시멘트와 커버 슬립을 체포. 핫 플레이트에서 2 분 동안 80 ℃에서 프로브와 동시에 슬라이드 변성. </li><li> 전송 습기 챔버에 슬라이드와 37 ° CO / N 피 빛 슬라이드를 품어. 배 SSC와 코 플린 항아리에 슬라이드를 세척하여 커버 전표를 제거합니다. 그리고 55-60 ° C의 2 배 SSC를 포함하는 코 플린 항아리에 넣어 슬라이드 20 분 동안 품어. </li><li> 실온에서 2 분 동안 코 플린 항아리에 SSC를 2 배 슬라이드를 놓습니다. 각각 70 %, 90 %, 100 % 에탄올, 일련의 2 분 동안 코 플린 항아리 슬라이드 탈수. </li><li> 강렬한 빛을 방지, antifade 설치 매체에 / ㎖ 4 &#39;, 6 diamidino-2-phenylindoline 1 μg의 (DAPI)과 슬라이드와 Counterstain과를 공기 - 건조. </li></ol> 3. 현미경 분석 및 저장 <ol><li> 표면 형광 현미경을 사용하여 슬라이드를 분석한다. 필터의 선택은 라벨 프로브 형광 색소 사용에 의존한다. 필요한 경우, 1 년까지 어두운 조건에서 4 ° C에서 저장 슬라이드. </li></ol>

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</ol>

The authors have nothing to disclose.

염색체 준비 실험 잔디 가족 (벼과)에 속하는 시리얼 어린 뿌리를 이용하여 수행되었다. 모든 분석 종은 이배체 게놈 세트 14 상대적으로 긴 유사 분열 중기 염색체 (11 ~ 15 μm의)가 큰 게놈 종 (5.1-7.9 GBP)에 속한다. 발아 한 뿌리의 길이가 세포 분열 조직의 최대치를 얻기 위해 2 cm 이상이 아니었다. 분열하는 세포의 동기화 유사 분열 중기의 수량이 10 퍼 향상 20 시간 긴 ...

계내 혼성화 (FISH)의 형광은 염색체 수준에서 단일 및 높은 복사 서열의 물리적 맵핑에 대한 효과적인 도구이다. 전제 조건은 높은 품질의 염색체 스프레드의 준비입니다. 동물과 식물 세포에 대한 동등하게 적합 할 것이 더 일반적인 염색체 준비 프로토콜이 없습니다. 식물 염색체의 준비로 인해 다른 종 내에서 단단한 세포벽과 각종 세포질의 일관성에 특히 도전이다. 식물 염색체의 제조를위한 바람직한 방법 중 하나는 드롭 확산 기법 및 공기 - 건조 기술로 알려진 1,2 소위 드롭 기술이다. 이 방법은 처음 체외 성장 포유 동물 세포 3 Rothfels과 Siminovitch에 의해 1958 년에 도입되었다. 나중에 마틴 등 알. 4 카토 등. 5는 식물이 방법을 적용. 최근 방법이라는 &#39;SteamDrop &amp;# 39; 비 중첩 염색체 (6)의 제조에 수증기를 사용하는 개발되었다. 높은 습도의 긍정적 인 영향은 이전 관찰되었지만 7 &#39;SteamDrop&#39;는 고품질 염색체 제제 (6)의 제어 흐름을 제공한다. 증기 처리는 아마도 염색체 단백질의 일부​​ 수정에 접속 염색체 연신시킨다. 전체 중기의 충분한 수의 고정 후속 물고기 실험은 기술적 인 전문 지식을 필요로 확산 있지만 중기 스프레드 결과의 품질은 매우 높다. 여기에서 우리는 단일 및 높은 사본 프로브 5,8의 물고기 검출에 적합한 유사 분열 시리얼 염색체의 제조를위한 프로토콜을 제시한다. 이 방법은 카토 50 % -55 %의 상대 습도 하에서 수행 (9) (도 1)에 의해 설명 풍건 적하 법의 개선 된 변이체이다. 이 프로토콜은 감소 된 수를 포함그 적용이 쉽고 효율적이고 재현하게 세척 단계. 우리가 Hordeum vulgare의, 수평 bulbosum, 수평 marinum, 수평 murinum, 수평 pubiflorum 및 Secale의 cereale 높은 품질의 염색체 확산과 물고기 결과를 얻었다이 프로토콜을 사용.

<table><tbody><tr><td>Hot Plate</td><td>MEDAX GmbH</td><td>12603</td><td></td></tr><tr><td>Cellulase R10</td><td>Duchefa</td><td>C8001</td><td></td></tr><tr><td>Cellulase&amp;nbsp;</td><td>CalBioChem</td><td>219466</td><td></td></tr><tr><td>Pectolyase</td><td>Sigma</td><td>P3026</td><td></td></tr><tr><td>Cytohelicase</td><td>Sigma</td><td>C8274</td><td></td></tr><tr><td>Texas Red-12-dUTP</td><td>Invitrogen</td><td>C3176</td><td>direct fluorochrome&amp;nbsp;</td></tr><tr><td>Fluor488-5-dUTP</td><td>Invitrogen</td><td>C11397</td><td>direct fluorochrome&amp;nbsp;</td></tr><tr><td>Fluorecsence microscope</td><td>Olympus BX61</td><td>BX61</td><td></td></tr><tr><td>CCD camera</td><td>Orca ER, Hamamatsu</td><td>C10600</td><td></td></tr><tr><td>4&amp;rsquo;,6-diamidino-2-phenylindole (DAPI)&amp;nbsp;</td><td>Vector Laboratories</td><td>H-1200</td><td>fluorecsent dye</td></tr></tbody></table>

a fast air-dry dropping chromosome preparation method suitable for fish in plants

염색체 스프레드의 제조 현장 하이브리드에 형광의 성공적인 성능 (FISH)을위한 전제 조건이다. 높은 품질의 식물 염색체 스프레드의 준비로 인해 단단한 세포벽에 도전한다. 식물 염색체의 제조를위한 승인 방법 중 하나는 소위 드롭 제제, 또한 드롭 확산 또는 공기 - 건조 기술로 알려져있다. 여기, 우리는 유사 분열 염색체의 빠른 준비를위한 프로토콜은 단일 및 높은 사본 DNA 프로브의 물고기 검출에 적합한 확산 제시한다. 이 방법은 50 % -55 %의 상대 습도 하에서 수행 풍건 드롭 방식의 개선 된 변이체이다. 이 프로토콜은 그 적용이 쉽고 효율적이고 재현하게 세척 단계의 감소 된 수를 포함한다. 이 방법의 명백한 이점은 성공적인 FISH 분석을위한 완벽한 전제 조건으로서 잘 확산, 손상되지 않은 수많은 중기 염색체이다. 이 프로토콜을 이용하여, 우리는 높은 품질을 얻을 CHROMosome 스프레드와 Hordeum vulgare의, 수평 bulbosum, 수평 marinum, 수평 murinum, 수평 pubiflorum 및 Secale의 cereale에 대한 재현 물고기 결과.

유사 분열 중기 스프레드 현미경 슬라이드는 전술 빠른 공기 건조 적하 염색체의 제조 방법에 의해 제조 하였다 (SUPPL.도 1). FISH 분석은 모두, 반복적이고 단일 - 카피 시퀀스를 사용하여 수행 하였다. 이미지는 대응하는 형광체의 여기를 가능 필터 세트 표면 형광 현미경에 의해 얻은 고감도 CCD 흑백 카메라에 의하여 촬영되었다. 화상 획득을 위해 우리는 화상 취득 소프트웨어가 설치...

Watch this Scientific Journal Video about A Fast Air-dry Dropping Chromosome Preparation Method Suitable for FISH in Plants at JoVE.com

A Fast Air-dry Dropping Chromosome Preparation Method Suitable for FISH in Plants

A protocol is described for the preparation of high-quality mitotic plant chromosome spreads by a fast air-dry dropping method suitable for the FISH detection of single and high copy DNA probes.

식물에서 물고기에 적합한 빠른 공기 건조 떨어 뜨리 염색체 제조 방법

Preparation of chromosome spreads is a prerequisite for the successful performance of fluorescence in situ hybridization (FISH). Preparation of high ...

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JoVE Journal

Biology

13.2K 조회수.  Leibniz Institute of Plant Genetics and Crop Plant Research (IPK). A protocol is described for the preparation of high-quality mitotic plant chromosome spreads by a fast air-dry dropping method suitable for the FISH detection of single and high copy DNA probes.

비디오: A Fast Air-dry Dropping Chromosome Preparation Method Suitable for FISH in Plants

Profiling DNA Replication Timing Using Zebrafish as an In Vivo Model System

DNA replication timing is an important cellular characteristic, exhibiting significant relationships with chromatin structure, transcription, and DNA mutation rates. Changes in replication timing occur during development and in cancer, but the role replication timing plays in development and disease is not known. Zebrafish were recently established as an in vivo model system to study replication timing. Here is detailed the protocols for using the zebrafish to determine DNA replication timing. After sorting cells from embryos and adult zebrafish, high-resolution genome-wide DNA replication timing patterns can be constructed by determining changes in DNA copy number through analysis of next generation sequencing data. The zebrafish model system allows for evaluation of the replication timing changes that occur in vivo throughout development, and can also be used to assess changes in individual cell types, disease models, or mutant lines. These methods will enable studies investigating the mechanisms and determinants of replication timing establishment and maintenance during development, the role replication timing plays in mutations and tumorigenesis, and the effects of perturbing replication timing on development and disease.

Profiling DNA Replication Timing Using Zebrafish as an In Vivo Model System

Zebrafish were recently used as an in vivo model system to study DNA replication timing during development. Here is detailed the protocols for using zebrafish embryos to profile replication timing. This protocol can be easily adapted to study replication timing in mutants, individual cell types, disease models, and other species.

DNA 복제 타이밍 Zebrafish Vivo에서 모델 시스템으로 사용 하 여 프로 파일링

DNA replication timing is an important cellular characteristic, exhibiting significant relationships with chromatin structure, transcription, and DNA ...

연구

유전학

Ploidy Manipulation of Zebrafish Embryos with Heat Shock 2 Treatment

Manipulation of ploidy allows for useful transformations, such as diploids to tetraploids, or haploids to diploids. In the zebrafish Danio rerio, specifically the generation of homozygous gynogenetic diploids is useful in genetic analysis because it allows the direct production of homozygotes from a single heterozygous mother. This article describes a modified protocol for ploidy duplication based on a heat pulse during the first cell cycle, Heat Shock 2 (HS2). Through inhibition of centriole duplication, this method results in a precise cell division stall during the second cell cycle. The precise one-cycle division stall, coupled to unaffected DNA duplication, results in whole genome duplication. Protocols associated with this method include egg and sperm collection, UV treatment of sperm, in vitro fertilization and heat pulse to cause a one-cell cycle division delay and ploidy duplication. A modified version of this protocol could be applied to induce ploidy changes in other animal species.

A modified protocol for ploidy manipulation uses a heat shock to induce a one-cycle stall in cytokinesis in the early embryo. This protocol is demonstrated in the zebrafish but may be applicable to other species.

열 충격이 치료와 제브라 피쉬 배아의 배수성 조작

Manipulation of ploidy allows for useful transformations, such as diploids to tetraploids, or haploids to diploids. In the zebrafish Danio rerio, ...

발생학

Fluorescent in situ Hybridization on Mitotic Chromosomes of Mosquitoes

Fluorescent in situ hybridization (FISH) is a technique routinely used by many laboratories to determine the chromosomal position of DNA and RNA probes. One important application of this method is the development of high-quality physical maps useful for improving the genome assemblies for various organisms. The natural banding pattern of polytene and mitotic chromosomes provides guidance for the precise ordering and orientation of the genomic supercontigs. Among the three mosquito genera, namely Anopheles, Aedes, and Culex, a well-established chromosome-based mapping technique has been developed only for Anopheles, whose members possess readable polytene chromosomes 1. As a result of genome mapping efforts, 88% of the An. gambiae genome has been placed to precise chromosome positions 2,3 . Two other mosquito genera, Aedes and Culex, have poorly polytenized chromosomes because of significant overrepresentation of transposable elements in their genomes 4, 5, 6. Only 31 and 9% of the genomic supercontings have been assigned without order or orientation to chromosomes of Ae. aegypti 7 and Cx. quinquefasciatus 8, respectively. Mitotic chromosome preparation for these two species had previously been limited to brain ganglia and cell lines. However, chromosome slides prepared from the brain ganglia of mosquitoes usually contain low numbers of metaphase plates 9. Also, although a FISH technique has been developed for mitotic chromosomes from a cell line of Ae. aegypti 10, the accumulation of multiple chromosomal rearrangements in cell line chromosomes 11 makes them useless for genome mapping. Here we describe a simple, robust technique for obtaining high-quality mitotic chromosome preparations from imaginal discs (IDs) of 4th instar larvae which can be used for all three genera of mosquitoes. A standard FISH protocol 12 is optimized for using BAC clones of genomic DNA as a probe on mitotic chromosomes of Ae. aegypti and Cx. quinquefasciatus, and for utilizing an intergenic spacer (IGS) region of ribosomal DNA (rDNA) as a probe on An. gambiae chromosomes. In addition to physical mapping, the developed technique can be applied to population cytogenetics and chromosome taxonomy/systematics of mosquitoes and other insect groups.

Fluorescent in situ Hybridization on Mitotic Chromosomes of Mosquitoes

Among the three mosquito genera, namely Anopheles, Aedes, and Culex, physical genome mapping techniques were established only for Anopheles, whose members possess readable polytene chromosomes. For the genera of Aedes and Culex, however, cytogenetic mapping remains challenging because of the poor quality of polytene chromosomes. Here we present a universal protocol for obtaining high-quality preparations of mitotic chromosomes and an optimized FISH protocol for all three genera of mosquitoes.

형광성의<em&gt; 현장에서</em모기의 Mitotic의 염색체에&gt; 하이브리드

Fluorescent in situ hybridization (FISH) is a technique routinely used by many laboratories to determine the chromosomal position of DNA and RNA probes. ...

면역학 및 감염병학

Preparation of Meiotic Chromosome Spreads from Zebrafish Spermatocytes

Meiosis is the key cellular process required to create haploid gametes for sexual reproduction. Model organisms have been instrumental in understanding the chromosome events that take place during meiotic prophase, including the pairing, synapsis, and recombination events that ensure proper chromosome segregation. While the mouse has been an important model for understanding the molecular mechanisms underlying these processes, not all meiotic events in this system are analogous to human meiosis. We recently demonstrated the exciting potential of the zebrafish as a model of human spermatogenesis. Here we describe, in detail, our methods to visualize meiotic chromosomes and associated proteins in chromosome spread preparations. These preparations have the advantage of allowing high resolution analysis of chromosome structures. First, we describe the procedure for dissecting testes from adult zebrafish, followed by cell dissociation, lysis, and spreading of the chromosomes. Next, we describe the procedure for detecting the localization of meiotic chromosome proteins, by immunofluorescence detection, and nucleic acid sequences, by fluorescence in situ hybridization (FISH). These techniques comprise a useful set of tools for the cytological analysis of meiotic chromatin architecture in the zebrafish system. Researchers in the zebrafish community should be able to quickly master these techniques and incorporate them into their standard analyses of reproductive function.

Nuclear surface spreads are an indispensable tool for studying chromosome events during meiosis. Here we demonstrate a method to prepare and visualize meiotic chromosomes during prophase I from zebrafish spermatocytes.

제브라피쉬 정자세포에서 메오틱 염색체 스프레드 의 준비

Meiosis is the key cellular process required to create haploid gametes for sexual reproduction. Model organisms have been instrumental in understanding ...

Co-expression of Multiple Chimeric Fluorescent Fusion Proteins in an Efficient Way in Plants

Information about the spatiotemporal subcellular localization(s) of a protein is critical to understand its physiological functions in cells. Fluorescent proteins and generation of fluorescent fusion proteins have been wildly used as an effective tool to directly visualize the protein localization and dynamics in cells. It is especially useful to compare them with well-known organelle markers after co-expression with the protein of interest. Nevertheless, classical approaches for protein co-expression in plants usually involve multiple independent expression plasmids, and therefore have drawbacks that include low co-expression efficiency, expression-level variation, and high time expenditure in genetic crossing and screening. In this study, we describe a robust and novel method for co-expression of multiple chimeric fluorescent proteins in plants. It overcomes the limitations of the conventional methods by using a single expression vector that is composed of multiple semi-independent expressing cassettes. Each protein expression cassette contains its own functional protein expression elements, and therefore it can be flexibly adjusted to meet diverse expression demand. Also, it is easy and convenient to perform the assembly and manipulation of DNA fragments in the expression plasmid by using an optimized one-step reaction without additional digestion and ligation steps. Furthermore, it is fully compatible with current fluorescent protein derived bio-imaging technologies and applications, such as FRET and BiFC. As a validation of the method, we employed this new system to co-express fluorescently fused vacuolar sorting receptor and secretory carrier membrane proteins. The results show that their perspective subcellular localizations are the same as in previous studies by both transient expression and genetic transformation in plants.

We have developed a novel method for co-expressing multiple chimeric fluorescent fusion proteins in plants to overcome the difficulties of conventional methods. It takes advantage of using a single expression plasmid that contains multiple functionally independent protein expressing cassettes to achieve protein co-expression.

식물에는 효율적인 방법으로 여러 공상 형광 성 융해 단백질의 공동 식

Information about the spatiotemporal subcellular localization(s) of a protein is critical to understand its physiological functions in cells. Fluorescent ...

화학

2D and 3D Chromosome Painting in Malaria Mosquitoes

Fluorescent in situ hybridization (FISH) of whole arm chromosome probes is a robust technique for mapping genomic regions of interest, detecting chromosomal rearrangements, and studying three-dimensional (3D) organization of chromosomes in the cell nucleus. The advent of laser capture microdissection (LCM) and whole genome amplification (WGA) allows obtaining large quantities of DNA from single cells. The increased sensitivity of WGA kits prompted us to develop chromosome paints and to use them for exploring chromosome organization and evolution in non-model organisms. Here, we present a simple method for isolating and amplifying the euchromatic segments of single polytene chromosome arms from ovarian nurse cells of the African malaria mosquito Anopheles gambiae. This procedure provides an efficient platform for obtaining chromosome paints, while reducing the overall risk of introducing foreign DNA to the sample. The use of WGA allows for several rounds of re-amplification, resulting in high quantities of DNA that can be utilized for multiple experiments, including 2D and 3D FISH. We demonstrated that the developed chromosome paints can be successfully used to establish the correspondence between euchromatic portions of polytene and mitotic chromosome arms in An. gambiae. Overall, the union of LCM and single-chromosome WGA provides an efficient tool for creating significant amounts of target DNA for future cytogenetic and genomic studies.

Chromosome painting is a useful method for studying organization of the cell nucleus and evolution of the karyotype. Here, we demonstrate an approach to isolate and amplify specific regions of interest from single polytene chromosomes that are subsequently used for two- and three-dimensional fluorescent in situ hybridization (FISH).

말라리아 모기의 2D 및 3D 염색체 페인팅

Fluorescent in situ hybridization (FISH) of whole arm chromosome probes is a robust technique for mapping genomic regions of interest, detecting ...

A High-Throughput Method For Zebrafish Sperm Cryopreservation and In Vitro Fertilization

This is a method for zebrafish sperm cryopreservation that is an adaptation of the Harvey method (Harvey et al., 1982).  We have introduced two changes to the original protocol that both streamline the procedure and increase sample uniformity.  First, we normalize all sperm volumes using freezing media that does not contain the cryoprotectant. Second, cryopreserved sperm are stored in cryovials instead of capillary tubes.  The rates of sperm freezing and thawing (&delta;&deg;C/time) are probably the two most critical variables to control in this procedure.  For this reason, do not substitute different tubes for those specified.  Working in teams of 2 it is possible to freeze the sperm of 100 males per team in ~2 hrs.  Sperm cryopreserved using this protocol has an average of 25% fertility (measured as the number of viable embryos generated in an in vitro fertilization divided by the total number of eggs fertilized) and this percent fertility is stable over many years.

A High-Throughput Method For Zebrafish Sperm Cryopreservation and In Vitro Fertilization

This is a high-throughput sperm cryopreservation protocol for zebrafish. Sperm cryopreserved using this protocol has an average of 25% fertility in subsequent vitro fertilization and is stable over many years.

높은 처리량 Zebrafish의 정자 Cryopreservation에 대한 방법과 체외에서 수정

This is a method for zebrafish sperm cryopreservation that is an adaptation of the Harvey method (Harvey et al., 1982).  We have introduced two changes to ...

생물학

Making Gynogenetic Diploid Zebrafish by Early Pressure

Heterozygosity in diploid eukaryotes often makes genetic studies cumbersome. Methods that produce viable homozygous diploid offspring directly from heterozygous females allow F1 mutagenized females to be screened directly for deleterious mutations in an accelerated forward genetic screen. Streisinger et al.1,2 described methods for making gynogenetic (homozygous) diploid zebrafish by activating zebrafish eggs with ultraviolet light-inactivated sperm and preventing either the second meiotic or the first zygotic cell division using physical treatments (heat or pressure) that deploymerize microtubules. The "early pressure" (EP) method blocks the meiosis II, which occurs shortly after fertilization. The EP method produces a high percentage of viable embryos that can develop to fertile adults of either sex. The method generates embryos that are homozygous at all loci except those that were separated from their centromere by recombination during meiosis I. Homozygous mutations are detected in EP clutches at between 50% for centromeric loci and less than 1% for telomeric loci. This method is reproduced verbatim from the Zebrafish Book3.

This is a method for generating gynogenetic diploid zebrafish embryos (embryos whose only genetic contribution comes from the mother) by blocking the second meiotic division immediately after fertilization with ultraviolet light-inactivated sperm. EP embryos are not fully homozygous due to recombination during the first meiotic division, however they are homozygous at all loci that have not been separated from their centromere by recombination.

초기 압력에 의해 Gynogenetic의 Diploid의 Zebrafish 만들기

Heterozygosity in diploid eukaryotes often makes genetic studies cumbersome. Methods that produce viable homozygous diploid offspring directly from ...

Slide Preparation Method to Preserve Three-dimensional Chromatin Architecture of Testicular Germ Cells

During testicular germ cell differentiation, the structure of nuclear chromatin dynamically changes. The following describes a method designed to preserve the three-dimensional chromatin arrangement of testicular germ cells found in mice; this method has been termed as the three-dimensional (3D) slide method. In this method, testicular tubules are directly treated with a permeabilization step that removes cytoplasmic material, followed by a fixation step that fixes nuclear materials. Tubules are then dissociated, the cell suspension is cytospun, and cells adhere to slides. This method improves sensitivity towards detection of subnuclear structures and is applicable for immunofluorescence, DNA, and RNA fluorescence in situ hybridization (FISH) and the combination of these detection methods. As an example of a possible application of the 3D slide method, a Cot-1 RNA FISH is shown to detect nascent RNAs. The 3D slide method will facilitate the detailed examination of spatial relationships between chromatin structure, DNA, and RNA during testicular germ cell differentiation.

The material here describes a method developed to preserve the three-dimensional chromatin structure of testicular germ cells. This has been termed the three-dimensional (3D) slide method. This method improves sensitivity for detection of subnuclear structures and is applicable for immunofluorescence, DNA, and RNA fluorescence in situ hybridization (FISH).

고환 세균 세포의 3차원 크로마틴 아키텍처를 보존하는 슬라이드 준비 방법

During testicular germ cell differentiation, the structure of nuclear chromatin dynamically changes. The following describes a method designed to preserve ...

Silencing the Spark: CRISPR/Cas9 Genome Editing in Weakly Electric Fish

Electroreception and electrogenesis have changed in the evolutionary history of vertebrates. There is a striking degree of convergence in these independently derived phenotypes, which share a common genetic architecture. This is perhaps best exemplified by the numerous convergent features of gymnotiforms and mormyrids, two species-rich teleost clades that produce and detect weak electric fields and are called weakly electric fish. In the 50 years since the discovery that weakly electric fish use electricity to sense their surroundings and communicate, a growing community of scientists has gained tremendous insights into evolution of development, systems and circuits neuroscience, cellular physiology, ecology, evolutionary biology, and behavior. More recently, there has been a proliferation of genomic resources for electric fish. Use of these resources has already facilitated important insights with regards to the connection between genotype and phenotype in these species. A major obstacle to integrating genomics data with phenotypic data of weakly electric fish is a present lack of functional genomics tools. We report here a full protocol for performing CRISPR/Cas9 mutagenesis that utilizes endogenous DNA repair mechanisms in weakly electric fish. We demonstrate that this protocol is equally effective in both the mormyrid species Brienomyrus brachyistius and the gymnotiform Brachyhypopomus gauderio by using CRISPR/Cas9 to target indels and point mutations in the first exon of the sodium channel gene scn4aa. Using this protocol, embryos from both species were obtained and genotyped to confirm that the predicted mutations in the first exon of the sodium channel scn4aa were present. The knock-out success phenotype was confirmed with recordings showing reduced electric organ discharge amplitudes when compared to uninjected size-matched controls.

Here, a protocol is presented to produce and rear CRISPR/Cas9 genome knockout electric fish. Outlined in detail are the required molecular biology, breeding, and husbandry requirements for both a gymnotiform and a mormyrid, and injection techniques to produce Cas9-induced indel F0 larvae.