Using site-specific nucleases to manipulate the zebrafish genome

项目来源

美国卫生和人类服务部基金(HHS)

项目主持人

SCHRAMM, CHARLENE A

项目受资助机构

UNIV OF MASSACHUSETTS MED SCH WORCESTER

立项年度

2017

立项时间

未公开

项目编号

5R01HL093766-10

项目级别

国家级

研究期限

未知 / 未知

受资助金额

418750.00美元

学科

Biotechnology;Genetics;Human Genome

学科代码

未公开

基金类别

Non-SBIR/STTR RPGs

关键词

未公开

参与者

LAWSON, NATHAN D; WOLFE, SCOT A

参与机构

NATIONAL HEART, LUNG, AND BLOOD INSTITUTE

项目标书摘要:DESCRIPTION (provided by applicant): The zebrafish has characteristics that make it an ideal model organism for studying genetic determinants that participate in development and disease. The advent of zinc finger nucleases, and more recently TAL-effector nucleases, has provided an accessible methodology for the targeted disruption of practically any gene within the zebrafish genome. However limitations still remain to the application of these site-specific nucleases (SSNs) in zebrafish, in particular for the generation of large deletions or tailor-made modifications to large coding (or non-coding) regions of the genome. Realizing this goal is critical to exploiting the full potential of the zebrafish as a developmental and disease model. In this grant application, we will rely on our established expertise in the field to optimize and exted the use of SSNs in zebrafish. To provide a foundation for our genome editing efforts, initial studies in Aim 1 will focus on increasing the efficiency of double-strand break formation by SSNs through improvements in the nuclease architecture. These improvements will be coupled to new methods to optimize the ratio of germline to somatic lesion frequency. In parallel, we will test the application of improved SSNs to rapidly interrogate gene function through efficient targeted biallelic somatic cell knockout. In particular, we will focus on development of approaches to allow biallelic gene knockout in a restricted somatic cell-type to facilitate analysi of cell autonomy. In Aim 2, we will apply SSNs to expand the repertoire of desired lesions that can be introduced at targeted sites in the zebrafish genome. This will include the application of SSNs to introduce large deletions and inversions through the use of multiple SSN pairs, as well as incorporation of domains that facilitate chromatin looping to generate efficient deletion of intervening genomic segments. We will also apply a similar approach to replace deleted regions with an exogenously supplied donor DNA to allow tailor-made alteration of the zebrafish genome. In Aim 3, we will apply improved SSNs to determine the function of non-coding sequences in the zebrafish genome during hematopoiesis and vascular development. In particular, we will introduce targeted deletions in the locus control (LCR) region of the major globin locus to determine its importance for globin switching during embryonic development. In parallel, we will apply SSNs to generate targeted deletions in miR-126a and b to determine the distinct roles of these microRNAs during flow- dependent and -independent vascular morphogenesis. The advances made in the context of the studies proposed in this application will enable the zebrafish community to create a variety of tailored genomic manipulations to facilitate detailed investigation of gene function. As we have in the past, we will continue to share all protocols and reagents that are developed in the course of these studies to facilitate their application within the community.

  • 排序方式:
  • 1
  • /
  • 1.Reverse Genetics in Zebrafish: Mutants, Morphants, and Moving Forward

    • 关键词:
    • ANTISENSE

    Gene editing in zebrafish has begun to reveal discordance between mutant phenotypes and those associated with knockdown via morpholino oligonucleotides (MOs). These studies suggest that MOs should not be used as a standalone tool and underscore the need for guidelines that require defined mutants to assess gene function in zebrafish.

    ...
  • 2.Creating and evaluating accurate CRISPR-Cas9 scalpels for genomic surgery

    • 关键词:
    • RNA-GUIDED ENDONUCLEASE; PLURIPOTENT STEM-CELLS; OFF-TARGET SITES;IN-VIVO; NUCLEASE SPECIFICITY; MAMMALIAN-CELLS; DNA CLEAVAGE;GENE-THERAPY; CAS SYSTEMS; CHROMOSOMAL REARRANGEMENTS

    The simplicity of site-specific genome targeting by type II clustered, regularly interspaced, short palindromic repeat (CRISPR)-Cas9 nucleases, along with their robust activity profile, has changed the landscape of genome editing. These favorable properties have made the CRISPR-Cas9 system the technology of choice for sequence-specific modifications in vertebrate systems. For many applications, whether the focus is on basic science investigations or therapeutic efficacy, activity and precision are important considerations when one is choosing a nuclease platform, target site and delivery method. Here we review recent methods for increasing the activity and accuracy of Cas9 and assessing the extent of off-target cleavage events.

    ...
  • 排序方式:
  • 1
  • /