Divergent effects of intrinsically active MEK variants on developmental Ras signaling.
Germline mutations in Ras pathway components are associated with a large class of human developmental abnormalities, known as RASopathies, that are characterized by a range of structural and functional phenotypes, including cardiac defects and neurocognitive delays. Although it is generally believed that RASopathies are caused by altered levels of pathway activation, the signaling changes in developing tissues remain largely unknown. We used assays with spatiotemporal resolution in Drosophila melanogaster (fruit fly) and Danio rerio (zebrafish) to quantify signaling changes caused by mutations in MAP2K1 (encoding MEK), a core component of the Ras pathway that is mutated in both RASopathies and cancers in humans. Surprisingly, we discovered that intrinsically active MEK variants can both increase and reduce the levels of pathway activation in vivo. The sign of the effect depends on cellular context, implying that some of the emerging phenotypes in RASopathies may be caused by increased, as well as attenuated, levels of Ras signaling.
Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey, USA.|Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, USA.|Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA.
Yogesh
Y
Goyal
Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey, USA.|Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, USA.|Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA.
Granton A
http://orcid.org/0000-0003-2803-9831
GA
Jindal
Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA.
José L
JL
Pelliccia
Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, USA.|Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA.
Kei
K
Yamaya
Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, USA.|Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA.
Eyan
E
Yeung
Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey, USA.|Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, USA.
Alan S
AS
Futran
Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA.
Rebecca D
http://orcid.org/0000-0001-6620-5015
RD
Burdine
Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA.
Trudi
T
Schüpbach
Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey, USA.|Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, USA.|Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA.
Stanislav Y
SY
Shvartsman
D000818:Animals; D004331:Drosophila melanogaster / Q000235:genetics; D018095:Germ-Line Mutation / Q000235:genetics*; D006331:Heart Diseases / Q000235:genetics; D006801:Humans; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics*; D009369:Neoplasms / Q000235:genetics; D019965:Neurocognitive Disorders / Q000235:genetics; D010641:Phenotype; D015398:Signal Transduction / Q000235:genetics*; D015027:Zebrafish / Q000235:genetics; D018631:ras Proteins / Q000235:genetics*
D020928:Mitogen-Activated Protein Kinases; D018631:ras Proteins