Month: September 2022

SECOND FINDING. "The molecular pathway directing hearts leftward—the nodal cascade—varies considerably among vertebrates (homology of form does not require homology of development) and was possibly co-opted from a preexisting asymmetrical chordate organ system." https://lnkd.in/dAEUFWY View in LinkedIn

THIRD FINDING. "Declining frequencies of spontaneous asymmetry reversal throughout vertebrate evolution suggest that heart development has become more canalized." https://lnkd.in/dAEUFWY View in LinkedIn

EARLIEST ASYMMETRY. "Over the past few decades, the C. elegans embryo has become a premiere system for studying cellular symmetry breaking in a developmental context. During C. elegans development, nearly every division produces daughter cells with different developmental trajectories." https://lnkd.in/dAxynvD View in LinkedIn

TWO SYSTEMS. "The nematode worm Caenorhabditis elegans has produced a wellspring of insights into mechanisms that govern cellular symmetry breaking during animal development. Here we focus on two highly conserved systems that underlie many of the key symmetry-breaking events that occur during embryonic and larval development in the worm." https://lnkd.in/dAxynvD View in LinkedIn

FIRST SYSTEM FOR SYMMETRY BREAKING. "One involves the interplay between Par proteins, Rho GTPases, and the actomyosin cytoskeleton and mediates asymmetric cell divisions that establish the germline.' https://lnkd.in/dAxynvD View in LinkedIn

CLEAVAGE FURROW AND POLARITY. "Interestingly, the embryo exploits elements of this same system to break symmetry during cleavage furrow specification and to establish apicobasal polarity in early embryonic cells and in the first true embryonic epithelia." https://lnkd.in/dAxynvD View in LinkedIn

SECOND SYSTEM FOR SYMMETRY BREAKING. "The other uses elements of the Wnt signaling pathway and a highly reiterative mechanism that distinguishes anterior from posterior daughter cell fates." https://lnkd.in/dAxynvD View in LinkedIn

DEVELOPMENTAL SYMMETRY BREAKING. "In some cases, these differences are imposed on daughters before or after division through inductive signals, but many of these divisions are intrinsically asymmetric—an initial symmetry-breaking step creates polarized distributions or activities of factors that control developmental potential." https://lnkd.in/dAxynvD View in LinkedIn

DIVERSITY FROM FEW SYSTEMS. "Registration of the cleavage plane with the axis of polarity then ensures differential inheritance of these potentials. With respect to cell fates, the output of these asymmetric divisions is amazingly diverse, yet the embryo seems to accomplish this diversity through variants of a few conserved symmetry-breaking systems." https://lnkd.in/dAxynvD View in LinkedIn

THE SPERM CUE. "Acting on an essentially unpolarized cell, the sperm cue triggers a rapid reorganization of the cell cortex, accompanied by the de novo enrichment of conserved polarity determinants known as Par proteins within complementary anterior and posterior cortical domains." https://lnkd.in/dAxynvD View in LinkedIn