Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Dec;16(6):e004262.
doi: 10.1161/CIRCGEN.123.004262. Epub 2023 Oct 31.

Hypertrophic Cardiomyopathy Secondary to RAF1 Cysteine-Rich Domain Variants

Dominic E Fullenkamp  1   2 , Ryan M Jorgensen  3 , Desiree F Leach  3 , Arjun Sinha  2 , Isabella M Salamone  1 , Jamie R Johnston  1 , Lisa M Dellefave-Castillo  1   2 , Lubna Choudhury  2 , Elizabeth M McNally  1   2 , Lisa D Wilsbacher  2   3   4
Affiliations

Hypertrophic Cardiomyopathy Secondary to RAF1 Cysteine-Rich Domain Variants

Dominic E Fullenkamp et al. Circ Genom Precis Med. 2023 Dec.
No abstract available

Keywords: Noonan syndrome; epidermal growth factor; humans; immunoblotting; phosphorylation.

PubMed Disclaimer

Conflict of interest statement

Disclosures Dr McNally is or was a consultant for Amgen, AstraZeneca, Avidity, Cytokinetics, Pfizer, PepGen, Stealth Biopharma, Tenaya, and Invitae. She is the founder of Ikaika Therapeutics, Inc. These relationships are unrelated to this article.

Figures

Figure 1.
Figure 1.
RAF1 protein map, clinical characterization of probands, and in vitro assessment of basal and epidermal growth factor (EGF)-stimulated MAPK/ERK kinase (MEK) phosphorylation of RAF F151L and RAF1 T145M compared to wild type RAF1. (A) RAF1 protein map. Horizontal lines represent areas where variants have been previously shown to be associated with Noonan-spectrum disease and HCM (CR2 and C-terminus). Vertical lines represent areas where variants have been associated with Noonan-spectrum disease without HCM. T145M and F151L represent variants described in this study. CR, conserved region; RBD, Ras-binding domain; CRD, cysteine-rich domain. (B) Top: ECG of RAF1 F151L proband, demonstrating left ventricular hypertrophy and classic apical variant HCM pattern with deep T wave inversion throughout the precordial leads. Bottom: Phase-sensitive inversion-recovery (PSIR) cardiac MRI demonstrated apical hypertrophy with a maximal wall thickness of 23 mm. Arrows denotes late gadolinium enhancement. Right ventricular hypertrophy was not present. (C) Top: ECG of T145M proband, demonstrating left ventricular hypertrophy and precordial T wave inversions. Bottom: Cardiac MRI PSIR image demonstrated left ventricular mid-to-apical hypertrophy with mid-to-apical myocardial delayed enhancement (arrowhead) and transmural scar in the aneurysmal true apex (arrow), consistent with the mid-ventricular subtype of HCM with an apical aneurysm. Right ventricular hypertrophy was not present. (D) Representative immunoblots of time course after EGF stimulation at t = 0, 5, 15, and 30 min. COS7 cells were transfected with expression plasmids coding for wild type (WT) RAF1 and RAF1 variants F151L and T145M (pCMV6-entry mammalian expression vector with a C-terminal Myc-DDK tag; PS100001, Origene; 1 mg DNA/420,000 cells). Top to bottom: Gel 1 immunoblot (Blot 1) was probed for RAF1 and phospho-MEK (pMEK); total protein served as loading control. Gel 2 was run in parallel, and the immunoblot (Blot 2) was probed for total MEK with total protein as loading control. Full immunoblots are available upon request. (E) Quantification, performed by an author blind to genotype, of pMEK/MEK normalized to RAF1 at t = 0 min and 30 min, demonstrating increased basal and increased stimulated pMEK activation (n = 3 per condition from independent transfections and different passages). *, p < 0.05, **, p < 0.01, and ***, p < 0.001 by 2-way ANOVA with correction for multiple comparisons.
See this image and copyright information in PMC

References

    1. Lynch A, Tatangelo M, Ahuja S, Fan C-PS, Min S, Lafreniere-Roula M, Papaz T, Zhou V, Armstrong K, Aziz PF, et al. Risk of Sudden Death in Patients With RASopathy Hypertrophic Cardiomyopathy. J Am Coll Cardiology. 2023;81:1035–1045. doi: doi:10.1016/j.jacc.2023.01.012 - DOI - PubMed
    1. Pandit B, Sarkozy A, Pennacchio LA, Carta C, Oishi K, Martinelli S, Pogna EA, Schackwitz W, Ustaszewska A, Landstrom A, et al. Gain-of-function RAF1 mutations cause Noonan and LEOPARD syndromes with hypertrophic cardiomyopathy. Nat Genet. 2007;39:1007–1012. doi: 10.1038/ng2073 - DOI - PubMed
    1. Daub M, Jockel J, Quack T, Weber CK, Schmitz F, Rapp UR, Wittinghofer A, Block C. The RafC1 cysteine-rich domain contains multiple distinct regulatory epitopes which control Ras-dependent Raf activation. Mol Cell Biol. 1998;18:6698–6710. doi: 10.1128/MCB.18.11.6698 - DOI - PMC - PubMed
    1. Spencer-Smith R, Terrell EM, Insinna C, Agamasu C, Wagner ME, Ritt DA, Stauffer J, Stephen AG, Morrison DK. RASopathy mutations provide functional insight into the BRAF cysteine-rich domain and reveal the importance of autoinhibition in BRAF regulation. Mol Cell. 2022;82:4262–4276.e4265. doi: 10.1016/j.molcel.2022.10.016 - DOI - PMC - PubMed
    1. Hoss S, Habib M, Silver J, Care M, Chan RH, Hanneman K, Morel CF, Iwanochko RM, Gollob MH, Rakowski H, et al. Genetic Testing for Diagnosis of Hypertrophic Cardiomyopathy Mimics. Circ Genom and Precis Med. 2020;13:e002748. doi: doi:10.1161/CIRCGEN.119.002748 - DOI - PubMed

Publication types