The Drosophila midkine/pleiotrophin homologues Miple1 and Miple2 affect adult lifespan but are dispensable for alk signaling during embryonic gut formation.
Midkine (MDK) and Pleiotrophin (PTN) are small heparin-binding cytokines with closely related structures. The Drosophila genome harbours two genes encoding members of the MDK/PTN family of proteins, known as miple1 and miple2. We have investigated the role of Miple proteins in vivo, in particular with regard to their proposed role as ligands for the Alk receptor tyrosine kinase (RTK). Here we show that Miple proteins are neither required to drive Alk signaling during Drosophila embryogenesis, nor are they essential for development in the fruit fly. Additionally we show that neither MDK nor PTN can activate hALK in vivo when ectopically co-expressed in the fly. In conclusion, our data suggest that Alk is not activated by MDK/PTN related growth factors Miple1 and Miple 2 in vivo.
Department of Molecular Biology, Umeå University, Umeå, Sweden.
Fredrik
F
Hugosson
Department of Molecular Biology, Umeå University, Umeå, Sweden.
Camilla
C
Sjögren
Department of Molecular Biology, Umeå University, Umeå, Sweden.
Anna
A
Birve
Department of Molecular Biology, Umeå University, Umeå, Sweden.
Ludmilla
L
Hedlund
Department of Molecular Biology, Umeå University, Umeå, Sweden.
Therese
T
Eriksson
Department of Molecular Biology, Umeå University, Umeå, Sweden; Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Göteborg, Sweden.
Ruth H
RH
Palmer
D000077548:Anaplastic Lymphoma Kinase; D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism; D016207:Cytokines / Q000235:genetics / Q000378:metabolism*; D004330:Drosophila / Q000196:embryology* / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D005260:Female; D017353:Gene Deletion; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D008297:Male; D000078792:Midkine; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism*; D015398:Signal Transduction
D002352:Carrier Proteins; D016207:Cytokines; D029721:Drosophila Proteins; C514347:Miple1 protein, Drosophila; C514348:Miple2 protein, Drosophila; C066845:pleiotrophin; D000078792:Midkine; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D020794:Receptor Protein-Tyrosine Kinases