A phenotype-based forward genetic screen identifies Dnajb6 as a sick sinus syndrome gene
- Mayo Clinic, United States
- University of Wisconsin-Madison, United States
- University of California, Davis, United States
- University of California, Irvine, United States
- University of Maryland, Baltimore, United States
- The University of Texas Health Science Center at Houston, United States
- Qingdao University, China
- Shanghai Jiao Tong University, China
Abstract
Previously we showed the generation of a protein trap library made with the gene-break transposon (GBT) in zebrafish (Danio rerio) that could be used to facilitate novel functional genome annotation towards understanding molecular underpinnings of human diseases (Ichino et al, 2020). Here, we report a significant application of this library for discovering essential genes for heart rhythm disorders such as sick sinus syndrome (SSS). SSS is a group of heart rhythm disorders caused by malfunction of the sinus node, the heart's primary pacemaker. Partially owing to its aging-associated phenotypic manifestation and low expressivity, molecular mechanisms of SSS remain difficult to decipher. From 609 GBT lines screened, we generated a collection of 35 zebrafish insertional cardiac (ZIC) mutants in which each mutant traps a gene with cardiac expression. We further employed electrocardiographic measurements to screen these 35 ZIC lines and identified three GBT mutants with SSS-like phenotypes. More detailed functional studies on one of the arrhythmogenic mutants, GBT411, in both zebrafish and mouse models unveiled Dnajb6 as a novel SSS causative gene with a unique expression pattern within the subpopulation of sinus node pacemaker cardiomyocytes that partially overlaps with the expression of hyperpolarization activated cyclic nucleotide gated channel 4 (Hcn4), supporting heterogeneity of the cardiac pacemaker cells.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files. Source data files have been provided for Figure 4 and Figure 7.
Article and author information
Author details
Funding
Mayo Foundation for Medical Education and Research
- Xiaolei Xu
Wisconsin Partnership Program 4140
- Alexey V Glukhov
American Heart Association (17POST33370089)
- Di Lang
American Heart Association (846898)
- Di Lang
National Institute of Health (R00HL138160)
- Stefano Morotti
National Institute of Health (1OT2OD026580-01)
- Eleonora Grandi
Science and Technology Innovation Action Plan of Shanghai (201409005600)
- Yigang Li
National Institute of Health (GM063904)
- Stephen C Ekker
American Heart Association (16SDG29120011)
- Alexey V Glukhov
National Institute of Health (R00HL138160)
- Stefano Morotti
National Institute of Health (R01HL131517,P01HL141084)
- Eleonora Grandi
American Heart Association (15SDG24910015)
- Eleonora Grandi
American Heart Association (20POST35120462)
- Haibo Ni
National Institute of Health (NIH R01HL141214)
- Alexey V Glukhov
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experiments were conducted in accordance with the Guidelines for the Care and Use of Laboratory Animals published by the US National Institutes of Health (publication No. 85-23, revised 1996). All animal procedures and protocols used in these studies (for zebrafish, #: A00005409-20; for mouse, #: A00003511-20 and M005490-R02) have been approved by the Mayo Clinic Institutional Animal Care and Use Committee (Permit number: D16-00187) and by the Animal Care and Use Committee of University of Wisconsin-Madison (Permit number: D16-00239).
Copyright
© 2022, Ding et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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A phenotype-based forward genetic screen identifies Dnajb6 as a sick sinus syndrome gene
eLife 11:e77327.
https://doi.org/10.7554/eLife.77327
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