XB-ART-54990J Biosci June 1, 2018; 43 (2): 375-390.
Spiral waves and vertebrate embryonic handedness.
During early embryonic development, the vertebrate main body axis is segmented from head-to-tail into somites. Somites emerge sequentially from the presomitic mesoderm (PSM) as a consequence of oscillatory waves of genetic activity, called somitogenesis waves. Here, we discuss the implications of the dynamic patterns of early X-Delta-2 expression in the prospective somites (somitomeres) of Xenopus laevis. We report that right somitomeres normally emerge before left to form chiral structures (i.e. structures having clockwise or counter-clockwise handedness). From our observations, we infer that somitogenesis waves are normally counter-clockwise spirals, a novel dynamic mechanism for the control of handedness development in Xenopus. We propose that the same mechanism could control handedness development in all vertebrate embryos, providing a dynamical basis for the current asymmetric molecular transport model for generating left-right asymmetry.
PubMed ID: 29872025
Species referenced: Xenopus laevis
Genes referenced: dlc hes4 hes5.7 nodal
GO keywords: somitogenesis
References [+] :
Aulehla, Oscillating signaling pathways during embryonic development. 2009, Pubmed