1. A transgene targeted to the zebrafishnkx2.4blocus drives specific<scp>green fluorescent protein</scp>expression and disrupts thyroid development
- Author
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David A. Hutcheson, Yuanyuan Xie, Priscilla Figueroa, and Richard I. Dorsky
- Subjects
0301 basic medicine ,endocrine system ,Transgene ,Green Fluorescent Proteins ,Thyroid Gland ,Locus (genetics) ,Biology ,Article ,Green fluorescent protein ,Animals, Genetically Modified ,03 medical and health sciences ,Exon ,0302 clinical medicine ,Animals ,Transgenes ,Allele ,Zebrafish ,Homeodomain Proteins ,Transcription activator-like effector nuclease ,Gene Expression Regulation, Developmental ,Zebrafish Proteins ,biology.organism_classification ,Null allele ,Cell biology ,030104 developmental biology ,embryonic structures ,030217 neurology & neurosurgery ,Developmental Biology - Abstract
Background With the goal of labeling and manipulating the zebrafish hypothalamus, we sought to target a green fluorescent protein (gfp) transgene to the expression domains of nkx2.4b, a gene expressed during hypothalamic and thyroid development. We combined transcription activator-like effector nucleases (TALENs)-mediated mutagenesis with a targeting construct to enable insertion of a gfp transgene into the endogenous nkx2.4b genomic locus. Results Injection of TALENs targeted to the first exon of nkx2.4b created a predicted null allele, and homozygous mutant embryos displayed loss of thyroid markers. From embryos injected with both TALENs and a targeting construct carrying a gfp transgene, we recovered a line in which GFP was expressed specifically in the hypothalamus and thyroid. Fish homozygous for this allele lacked exon 1 of nkx2.4b and exhibited hypothyroid phenotypes. Conclusions By combining TALENs injections with a targeting construct that contained a gfp transgene, we were able to recover an allele in which GFP is expressed in the nkx2.4b expression domains, with homozygous phenotypes suggesting the creation of a loss-of-function transgenic line. These results demonstrate the creation of a useful tool for studying hypothalamus and thyroid development.
- Published
- 2020