TY - JOUR
T1 - Heartbroken is a specific downstream mediator of FGF receptor signalling in Drosophila
AU - Michelson, Alan M.
AU - Gisselbrecht, Stephen
AU - Buff, Eugene
AU - Skeath, James B.
PY - 1998
Y1 - 1998
N2 - Drosophila possesses two FGF receptors which are encoded by the heartless and breathless genes. HEARTLESS is essential for early migration and patterning of the embryonic mesoderm, while BREATHLESS is required for proper branching of the tracheal system. We have identified a new gene, heartbroken, that participates in the signalling pathways of both FGF receptors. Mutations in heartbroken are associated with defects in the migration and later specification of mesodermal and tracheal cells. Genetic interaction and epistasis experiments indicate that heartbroken acts downstream of the two FGF receptors but either upstream of or parallel to RAS1. Furthermore, heartbroken is involved in both the HEARTLESS- and BREATHLESS-dependent activation of MAPK. In contrast, EGF receptor-dependent embryonic functions and MAPK activation are not perturbed in heartbroken mutant embryos. A strong heartbroken allele also suppresses the effects of hyperactivated FGF but not EGF receptors. Thus, heartbroken may contribute to the specificity of developmental responses elicited by FGF receptor signalling.
AB - Drosophila possesses two FGF receptors which are encoded by the heartless and breathless genes. HEARTLESS is essential for early migration and patterning of the embryonic mesoderm, while BREATHLESS is required for proper branching of the tracheal system. We have identified a new gene, heartbroken, that participates in the signalling pathways of both FGF receptors. Mutations in heartbroken are associated with defects in the migration and later specification of mesodermal and tracheal cells. Genetic interaction and epistasis experiments indicate that heartbroken acts downstream of the two FGF receptors but either upstream of or parallel to RAS1. Furthermore, heartbroken is involved in both the HEARTLESS- and BREATHLESS-dependent activation of MAPK. In contrast, EGF receptor-dependent embryonic functions and MAPK activation are not perturbed in heartbroken mutant embryos. A strong heartbroken allele also suppresses the effects of hyperactivated FGF but not EGF receptors. Thus, heartbroken may contribute to the specificity of developmental responses elicited by FGF receptor signalling.
KW - Cell migration
KW - Drosophila
KW - FGF
KW - Mesoderm
KW - Receptor tyrosine kinase
KW - Trachea
UR - http://www.scopus.com/inward/record.url?scp=0031699463&partnerID=8YFLogxK
U2 - 10.1242/dev.125.22.4379
DO - 10.1242/dev.125.22.4379
M3 - Article
C2 - 9778498
AN - SCOPUS:0031699463
SN - 0950-1991
VL - 125
SP - 4379
EP - 4389
JO - Development
JF - Development
IS - 22
ER -