title: Sprouty2 mediated tuning of signalling is essential for somite myogenesis.
abstract: BACKGROUND
  Negative regulators of signal transduction cascades play critical roles in controlling different aspects of normal embryonic development. Sprouty2 (Spry2) negatively regulates receptor tyrosine kinases (RTK) and FGF signalling and is important in differentiation, cell migration and proliferation. In vertebrate embryos, Spry2 is expressed in paraxial mesoderm and in forming somites. Expression is maintained in the myotome until late stages of somite differentiation. However, its role and mode of action during somite myogenesis is still unclear.
  
  
  RESULTS
  Here, we analysed chick Spry2 expression and showed that it overlaps with that of myogenic regulatory factors MyoD and Mgn. Targeted mis-expression of Spry2 led to inhibition of myogenesis, whilst its C-terminal domain led to an increased number of myogenic cells by stimulating cell proliferation.
  
  
  CONCLUSIONS
  Spry2 is expressed in somite myotomes and its expression overlaps with myogenic regulatory factors. Overexpression and dominant-negative interference showed that Spry2 plays a crucial role in regulating chick myogenesis by fine tuning of FGF signaling through a negative feedback loop. We also propose that mir-23, mir-27 and mir-128 could be part of the negative feedback loop mechanism. Our analysis is the first to shed some light on in vivo Spry2 function during chick somite myogenesis.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Abu-Elmagd
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Goljanek Whysall
authors.forename: Grant
authors.initials: G
authors.lastname: Wheeler
authors.forename: Andrea
authors.initials: A
authors.lastname: Münsterberg
mesh_terms: D000818:Animals; D002645:Chickens; D025461:Feedback, Physiological; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism*; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism; D008938:Mitosis; D024510:Muscle Development; D015398:Signal Transduction; D019170:Somites / Q000166:cytology / Q000196:embryology*
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D035683:MicroRNAs; D016222:Fibroblast Growth Factor 2