Twisting of the zebrafish heart tube during cardiac looping is a tbx5-dependent and tissue-intrinsic process

TY - JOUR

T1 - Twisting of the zebrafish heart tube during cardiac looping is a tbx5-dependent and tissue-intrinsic process

AU - Tessadori, Federico

AU - Tsingos, Erika

AU - Colizzi, Enrico Sandro

AU - Kruse, Fabian

AU - van den Brink, Susanne C

AU - van den Boogaard, Malou

AU - Christoffels, Vincent M

AU - Merks, Roeland Mh

AU - Bakkers, Jeroen

N1 - © 2021, Tessadori et al.

PY - 2021/8/10

Y1 - 2021/8/10

N2 - Organ laterality refers to the left-right asymmetry in disposition and conformation of internal organs and is established during embryogenesis. The heart is the first organ to display visible left-right asymmetries through its left-sided positioning and rightward looping. Here, we present a new zebrafish loss-of-function allele for tbx5a, which displays defective rightward cardiac looping morphogenesis. By mapping individual cardiomyocyte behavior during cardiac looping, we establish that ventricular and atrial cardiomyocytes rearrange in distinct directions. As a consequence, the cardiac chambers twist around the atrioventricular canal resulting in torsion of the heart tube, which is compromised in tbx5a mutants. Pharmacological treatment and ex vivo culture establishes that the cardiac twisting depends on intrinsic mechanisms and is independent from cardiac growth. Furthermore, genetic experiments indicate that looping requires proper tissue patterning. We conclude that cardiac looping involves twisting of the chambers around the atrioventricular canal, which requires correct tissue patterning by Tbx5a.

AB - Organ laterality refers to the left-right asymmetry in disposition and conformation of internal organs and is established during embryogenesis. The heart is the first organ to display visible left-right asymmetries through its left-sided positioning and rightward looping. Here, we present a new zebrafish loss-of-function allele for tbx5a, which displays defective rightward cardiac looping morphogenesis. By mapping individual cardiomyocyte behavior during cardiac looping, we establish that ventricular and atrial cardiomyocytes rearrange in distinct directions. As a consequence, the cardiac chambers twist around the atrioventricular canal resulting in torsion of the heart tube, which is compromised in tbx5a mutants. Pharmacological treatment and ex vivo culture establishes that the cardiac twisting depends on intrinsic mechanisms and is independent from cardiac growth. Furthermore, genetic experiments indicate that looping requires proper tissue patterning. We conclude that cardiac looping involves twisting of the chambers around the atrioventricular canal, which requires correct tissue patterning by Tbx5a.

KW - Animals

KW - Body Patterning

KW - Embryo, Nonmammalian/embryology

KW - Heart/embryology

KW - Organogenesis/genetics

KW - Transcription Factors/genetics

KW - Zebrafish/embryology

KW - Zebrafish Proteins/genetics

U2 - 10.7554/eLife.61733

DO - 10.7554/eLife.61733

M3 - Article

C2 - 34372968

SN - 2050-084X

VL - 10

JO - eLife

JF - eLife

ER -