title: EGFR signalling is required for Paracentrotus lividus endomesoderm specification.
abstract: The EGFR pathway is critical for cell fate specification throughout the development of several organisms. Here we identified in sea urchin an EGFR-related antigen maternally expressed and showing a dynamic pattern of localization during development. To investigate the role played by the EGFR in Paracentrotus lividus development we blocked its activity by using the EGFR kinase inhibitor AG1478. This treatment produces decrease of EGFR phosphorylation, and embryos with various defects especially in the endomesoderm territory until to obtain an animalized phenotype. These effects are rescued by the addition of TGF-alpha, an EGFR ligand. The role played by EGFR-like along the animal/vegetal axis was also detected, after AG1478 treatment, by the extended distribution of HE and decreased nuclearization of beta-catenin in vegetal cells. Moreover, inhibition of EGFR-like reduced ERK phosphorylation, necessary for cell fate specification in the micromeres and their derivates. Taken together these results indicate that EGFR-like activity is required both for A/V axis formation and endomesoderm differentiation.
authors.affiliation: Istituto di Biomedicina ed Immunologia Molecolare (IBIM) "Alberto Monroy", CNR, sez. Biologia dello Sviluppo, via Ugo La Malfa 153, 90146 Palermo, PA, Italy.
authors.forename: Daniele P
authors.initials: DP
authors.lastname: Romancino
authors.forename: Giovanna
authors.initials: G
authors.lastname: Montana
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Cavalieri
authors.forename: Giovanni
authors.initials: G
authors.lastname: Spinelli
authors.forename: Marta
authors.initials: M
authors.lastname: Di Carlo
mesh_terms: D000818:Animals; D015153:Blotting, Western; D019070:Cell Lineage; D004625:Embryo, Nonmammalian / Q000187:drug effects; D004707:Endoderm / Q000166:cytology*; D066246:ErbB Receptors / Q000378:metabolism*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D007150:Immunohistochemistry; D020935:MAP Kinase Signaling System; D008648:Mesoderm / Q000166:cytology*; D047328:Paracentrotus / Q000196:embryology*; D011799:Quinazolines; D015398:Signal Transduction; D020032:Tyrphostins / Q000494:pharmacology
chemical_list: D011799:Quinazolines; D020032:Tyrphostins; C101044:RTKI cpd; D066246:ErbB Receptors; D048049:Extracellular Signal-Regulated MAP Kinases