Header

UZH-Logo

Maintenance Infos

Early frameshift alleles of zebrafish tbx5a that fail to develop the heartstrings phenotype


Chiavacci, Elena; Kirchgeorg, Lucia; Felker, Anastasia; Burger, Alexa; Mosimann, Christian (2017). Early frameshift alleles of zebrafish tbx5a that fail to develop the heartstrings phenotype. Matters:1-7.

Abstract

Tbx5 is a key transcription factor for vertebrate heart and forelimb development that causes Holt-Oram syndrome when mutated in humans. The classic zebrafish mutant for tbx5a named heartstrings (hst) features recessive absence of pectoral fins and a spectrum of heart defects, most-prominently featuring the name-giving stretched heart tube. The mutation of the hst allele is a stop codon that is predicted to result in a truncated Tbx5a protein that might feature residual activity. Here, using CRISPR-Cas9 mutagenesis, we generated zebrafish strains for two new tbx5a frameshift alleles in the first coding exon: tbx5a c.21_25del and tbx5a c.22_31del, abbreviated as tbx5aΔ5 and tbx5aΔ10. Homozygous and trans-heterozygous combinations of these new tbx5a alleles cause fully penetrant loss of pectoral fins and heart defects including changes in cardiac marker expression akin to hst mutants. Nonetheless, distinct from hst mutants, homozygous and trans-heterozygous combinations of these tbx5a frameshift mutants do not readily manifest the stretched hst heart phenotype. Our observation points out the importance and value of comparing phenotypes from different classes of mutant alleles per gene.

Abstract

Tbx5 is a key transcription factor for vertebrate heart and forelimb development that causes Holt-Oram syndrome when mutated in humans. The classic zebrafish mutant for tbx5a named heartstrings (hst) features recessive absence of pectoral fins and a spectrum of heart defects, most-prominently featuring the name-giving stretched heart tube. The mutation of the hst allele is a stop codon that is predicted to result in a truncated Tbx5a protein that might feature residual activity. Here, using CRISPR-Cas9 mutagenesis, we generated zebrafish strains for two new tbx5a frameshift alleles in the first coding exon: tbx5a c.21_25del and tbx5a c.22_31del, abbreviated as tbx5aΔ5 and tbx5aΔ10. Homozygous and trans-heterozygous combinations of these new tbx5a alleles cause fully penetrant loss of pectoral fins and heart defects including changes in cardiac marker expression akin to hst mutants. Nonetheless, distinct from hst mutants, homozygous and trans-heterozygous combinations of these tbx5a frameshift mutants do not readily manifest the stretched hst heart phenotype. Our observation points out the importance and value of comparing phenotypes from different classes of mutant alleles per gene.

Statistics

Citations

Dimensions.ai Metrics

Altmetrics

Downloads

3 downloads since deposited on 19 Jan 2018
3 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Institute of Molecular Life Sciences
Dewey Decimal Classification:570 Life sciences; biology
Language:English
Date:11 April 2017
Deposited On:19 Jan 2018 19:58
Last Modified:19 Feb 2018 10:29
Publisher:ScienceMatters AG
ISSN:2297-8240
OA Status:Hybrid
Free access at:Publisher DOI. An embargo period may apply.
Publisher DOI:https://doi.org/10.19185/matters.201703000011

Download

Download PDF  'Early frameshift alleles of zebrafish tbx5a that fail to develop the heartstrings phenotype'.
Preview
Content: Published Version
Language: English
Filetype: PDF
Size: 1MB
View at publisher
Licence: Creative Commons: Attribution 4.0 International (CC BY 4.0)