Bi-allelic variants in IPO8 cause a connective tissue disorder associated with cardiovascular defects, skeletal abnormalities, and immune dysregulation.

Fiche publication

Date publication

mai 2021

Journal

American journal of human genetics

Auteurs

Membres identifiés du Cancéropôle Est :
Pr FAIVRE Laurence

Tous les auteurs :
Ziegler A, Duclaux-Loras R, Revenu C, Charbit-Henrion F, Begue B, Duroure K, Grimaud L, Guihot AL, Desquiret-Dumas V, Zarhrate M, Cagnard N, Mas E, Breton A, Edouard T, Billon C, Frank M, Colin E, Lenaers G, Henrion D, Lyonnet S, Faivre L, Alembik Y, Philippe A, Moulin B, Reinstein E, Tzur S, Attali R, McGillivray G, White SM, Gallacher L, Kutsche K, Schneeberger P, Girisha KM, Nayak SS, Pais L, Maroofian R, Rad A, Vona B, Karimiani EG, Lekszas C, Haaf T, Martin L, Ruemmele F, Bonneau D, Cerf-Bensussan N, Del Bene F, Parlato M

Lien Pubmed

https://www.ncbi.nlm.nih.gov/pubmed/34010604

Résumé

Dysregulated transforming growth factor TGF-β signaling underlies the pathogenesis of genetic disorders affecting the connective tissue such as Loeys-Dietz syndrome. Here, we report 12 individuals with bi-allelic loss-of-function variants in IPO8 who presented with a syndromic association characterized by cardio-vascular anomalies, joint hyperlaxity, and various degree of dysmorphic features and developmental delay as well as immune dysregulation; the individuals were from nine unrelated families. Importin 8 belongs to the karyopherin family of nuclear transport receptors and was previously shown to mediate TGF-β-dependent SMADs trafficking to the nucleus in vitro. The important in vivo role of IPO8 in pSMAD nuclear translocation was demonstrated by CRISPR/Cas9-mediated inactivation in zebrafish. Consistent with IPO8's role in BMP/TGF-β signaling, ipo8 zebrafish presented mild to severe dorso-ventral patterning defects during early embryonic development. Moreover, ipo8 zebrafish displayed severe cardiovascular and skeletal defects that mirrored the human phenotype. Our work thus provides evidence that IPO8 plays a critical and non-redundant role in TGF-β signaling during development and reinforces the existing link between TGF-β signaling and connective tissue defects.