Reference SummaryHernandez-Porras I, Proc Natl Acad Sci U S A 2014 Nov 18;111(46):16395-400

Title

K-RasV14I recapitulates Noonan syndrome in mice.

Authors

Hernandez-Porras I; Fabbiano S; Schuhmacher AJ; Aicher A; Canamero M; Camara JA; Cusso L; Desco M; Heeschen C; Mulero F; Bustelo XR; Guerra C; Barbacid M

Journal

Proc Natl Acad Sci U S A

Volume

111

Issue

46

Year

2014

Pages

16395-400

Abstract

Noonan syndrome (NS) is an autosomal dominant genetic disorder characterized by short stature, craniofacial dysmorphism, and congenital heart defects. NS also is associated with a risk for developing myeloproliferative disorders (MPD), including juvenile myelomonocytic leukemia (JMML). Mutations responsible for NS occur in at least 11 different loci including KRAS. Here we describe a mouse model for NS induced by K-Ras(V14I), a recurrent KRAS mutation in NS patients. K-Ras(V14I)-mutant mice displayed multiple NS-associated developmental defects such as growth delay, craniofacial dysmorphia, cardiac defects, and hematologic abnormalities including a severe form of MPD that resembles human JMML. Homozygous animals had perinatal lethality whose penetrance varied with genetic background. Exposure of pregnant mothers to a MEK inhibitor rescued perinatal lethality and prevented craniofacial dysmorphia and cardiac defects. However, Mek inhibition was not sufficient to correct these defects when mice were treated after weaning. Interestingly, Mek inhibition did not correct the neoplastic MPD characteristic of these mutant mice, regardless of the timing at which the mice were treated, thus suggesting that MPD is driven by additional signaling pathways. These genetically engineered K-Ras(V14I)-mutant mice offer an experimental tool for studying the molecular mechanisms underlying the clinical manifestations of NS. Perhaps more importantly, they should be useful as a preclinical model to test new therapies aimed at preventing or ameliorating those deficits associated with this syndrome.

Links

J:223433 – MGI References
25359213 – National Library of Medicine/PubMed

Strain Notes

Strain Note
B6;129-Krastm4.1Bbd The genetic background of these mice was stated to be mixed C57BL/6J x 129 (including at least 129X1/SvJ and 129S1/SvJ) but also may have included some FVB/N.
B6;129-Krastm4.1Bbd/+ The genetic background of these mice was stated to be mixed C57BL/6J x 129 (including at least 129X1/SvJ and 129S1/SvJ) but also may have included some FVB/N.

Models

Strain Model Name Treatment Agent(s) Organ Affected Frequency Model Details
B6;129-Krastm4.1Bbd/+ Leukocyte - Myelocyte (Granulocyte) hyperplasia Spleen

100

B6;129-Krastm4.1Bbd/+ Leukocyte - Myelocyte (Granulocyte) hyperplasia
  • PD0325901 (MEK inhibitor)
Spleen

100

B6;129-Krastm4.1Bbd Leukocyte - Myelocyte (Granulocyte) hyperplasia Spleen

100

B6;129-Krastm4.1Bbd Leukocyte - Myelocyte (Granulocyte) hyperplasia
  • PD0325901 (MEK inhibitor)
Spleen

100