Embryological basis for cardiac left-right asymmetry.
Asymmetric heart tube looping and chamber morphogenesis is a complex process that is just beginning to be understood at the genetic level. Rightward looping is the first embryological manifestation of consistently oriented, left-right asymmetric development of nearly all visceral organs. Intuitively, invariant anatomical asymmetry must derive from a novel mechanism capable of integrating dorsoventral and anteroposterior information. The details of this process are emerging for several vertebrates and reveal that overall left-right asymmetry, once polarized with respect to dorsoventral and anteroposterior axes, unfolds through distinct left- and right-sided programs of gene expression. These, in turn, regulate expression of cardiac and chamber-specific genes which guide heart morphogenesis and differentiation.
Mercola
M
M
Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
D000818:Animals; D019521:Body Patterning / Q000235:genetics / Q000502:physiology; D002642:Chick Embryo; D004622:Embryo, Mammalian / Q000502:physiology; D004625:Embryo, Nonmammalian / Q000502:physiology; D017629:Gap Junctions / Q000502:physiology; D018507:Gene Expression Regulation, Developmental; D006321:Heart / Q000196:embryology* / Q000502:physiology*; D051379:Mice; D009024:Morphogenesis / Q000235:genetics / Q000502:physiology; D014781:Viscera / Q000196:embryology; D014981:Xenopus; D015027:Zebrafish