title: Migration of zebrafish primordial germ cells: a role for myosin contraction and cytoplasmic flow.
abstract: The molecular and cellular mechanisms governing cell motility and directed migration in response to the chemokine SDF-1 are largely unknown. Here, we demonstrate that zebrafish primordial germ cells whose migration is guided by SDF-1 generate bleb-like protrusions that are powered by cytoplasmic flow. Protrusions are formed at sites of higher levels of free calcium where activation of myosin contraction occurs. Separation of the acto-myosin cortex from the plasma membrane at these sites is followed by a flow of cytoplasm into the forming bleb. We propose that polarized activation of the receptor CXCR4 leads to a rise in free calcium that in turn activates myosin contraction in the part of the cell responding to higher levels of the ligand SDF-1. The biased formation of new protrusions in a particular region of the cell in response to SDF-1 defines the leading edge and the direction of cell migration.
authors.affiliation: Germ Cell Development, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany.
authors.forename: Heiko
authors.initials: H
authors.lastname: Blaser
authors.forename: Michal
authors.initials: M
authors.lastname: Reichman-Fried
authors.forename: Irinka
authors.initials: I
authors.lastname: Castanon
authors.forename: Karin
authors.initials: K
authors.lastname: Dumstrei
authors.forename: Florence L
authors.initials: FL
authors.lastname: Marlow
authors.forename: Koichi
authors.initials: K
authors.lastname: Kawakami
authors.forename: Lilianna
authors.initials: L
authors.lastname: Solnica-Krezel
authors.forename: Carl-Philipp
authors.initials: CP
authors.lastname: Heisenberg
authors.forename: Erez
authors.initials: E
authors.lastname: Raz
mesh_terms: D000199:Actins / Q000502:physiology; D000818:Animals; D002462:Cell Membrane / Q000502:physiology; D016764:Cell Polarity; D054377:Chemokine CXCL12; D019743:Chemokines, CXC / Q000502:physiology; D002633:Chemotaxis; D003593:Cytoplasm / Q000502:physiology*; D003599:Cytoskeleton / Q000502:physiology; D005854:Germ Cells / Q000502:physiology*; D009218:Myosins / Q000502:physiology*; D011554:Pseudopodia / Q000502:physiology; D019718:Receptors, CXCR4 / Q000502:physiology; D015027:Zebrafish / Q000196:embryology / Q000502:physiology*; D029961:Zebrafish Proteins / Q000502:physiology*
chemical_list: D000199:Actins; D054377:Chemokine CXCL12; D019743:Chemokines, CXC; D019718:Receptors, CXCR4; D029961:Zebrafish Proteins; D009218:Myosins