@article {931, title = {Mutations in GRK2 cause Jeune syndrome by impairing Hedgehog and canonical Wnt signaling.}, journal = {EMBO Mol Med}, volume = {12}, year = {2020}, month = {2020 11 06}, pages = {e11739}, abstract = {

Mutations in genes affecting primary cilia cause ciliopathies, a diverse group of disorders often affecting skeletal development. This includes Jeune syndrome or asphyxiating thoracic dystrophy (ATD), an autosomal recessive skeletal disorder. Unraveling the responsible molecular pathology helps illuminate mechanisms responsible for functional primary cilia. We identified two families with ATD caused by loss-of-function mutations in the gene encoding adrenergic receptor kinase 1 (ADRBK1 or GRK2). GRK2 cells from an affected individual homozygous for the p.R158* mutation resulted in loss of GRK2, and disrupted chondrocyte growth and differentiation in the cartilage growth plate. GRK2 null cells displayed normal cilia morphology, yet loss of GRK2 compromised cilia-based signaling of Hedgehog (Hh) pathway. Canonical Wnt signaling was also impaired, manifested as a failure to respond to Wnt ligand due to impaired phosphorylation of the Wnt co-receptor LRP6. We have identified GRK2 as an essential regulator of skeletogenesis and demonstrate how both Hh and Wnt signaling mechanistically contribute to skeletal ciliopathies.

}, issn = {1757-4684}, doi = {10.15252/emmm.201911739}, author = {Bosakova, Michaela and AbrAHm, Sara P and Nita, Alexandru and Hruba, Eva and Buchtova, Marcela and Taylor, S Paige and Duran, Ivan and Martin, Jorge and Svozilova, Katerina and Barta, Tomas and Varecha, Miroslav and Balek, Lukas and Kohoutek, Jiri and Radaszkiewicz, Tomasz and Pusapati, Ganesh V and Bryja, Vitezslav and Rush, Eric T and Thiffault, Isabelle and Nickerson, Deborah A and Bamshad, Michael J and Rohatgi, Rajat and Cohn, Daniel H and Krakow, Deborah and Krejci, Pavel} } @article {400, title = {Mutations in IFT-A satellite core component genes and produce short rib polydactyly syndrome with distinctive campomelia.}, journal = {Cilia}, volume = {6}, year = {2017}, month = {2017}, pages = {7}, abstract = {

BACKGROUND: Skeletal ciliopathies comprise a spectrum of ciliary malfunction disorders that have a profound effect on the skeleton. Most common among these disorders is short rib polydactyly syndrome (SRPS), a recessively inherited perinatal lethal condition characterized by a long narrow chest, markedly shortened long bones, polydactyly and, often, multi-organ system involvement. SRPS shows extensive locus heterogeneity with mutations in genes encoding proteins that participate in cilia formation and/or function.

RESULTS: Herein we describe mutations in , a satellite member of the retrograde IFT-A complex, that produce a form of SRPS with unusual bending of the ribs and appendicular bones. These newly described mutations disrupted cilia formation, produced abnormalities in cartilage growth plate architecture thus contributing to altered endochondral ossification. We further show that the SRPS phenotype is similar to SRPS resulting from mutations in the gene encoding IFT121 (WDR35), a direct interactor with IFT43.

CONCLUSIONS: This study defines a new -associated phenotype, identifying an additional locus for SRPS. The data demonstrate that IFT43 is essential for ciliogenesis and that the mutations disrupted the orderly proliferation and differentiation of growth plate chondrocytes, resulting in a severe effect on endochondral ossification and mineralization. Phenotypic similarities with SRPS cases resulting from mutations in the gene encoding the IFT43 direct interacting protein IFT121 suggests that similar mechanisms may be disrupted by defects in these two IFT-A satellite interactors.

}, issn = {2046-2530}, doi = {10.1186/s13630-017-0051-y}, author = {Duran, Ivan and Taylor, S Paige and Zhang, Wenjuan and Martin, Jorge and Qureshi, Faisal and Jacques, Suzanne M and Wallerstein, Robert and Lachman, Ralph S and Nickerson, Deborah A and Bamshad, Michael and Cohn, Daniel H and Krakow, Deborah} } @article {156, title = {Mutations in DYNC2LI1 disrupt cilia function and cause short rib polydactyly syndrome.}, journal = {Nat Commun}, volume = {6}, year = {2015}, month = {2015 Jun 16}, pages = {7092}, abstract = {

The short rib polydactyly syndromes (SRPSs) are a heterogeneous group of autosomal recessive, perinatal lethal skeletal disorders characterized primarily by short, horizontal ribs, short limbs and polydactyly. Mutations in several genes affecting intraflagellar transport (IFT) cause SRPS but they do not account for all cases. Here we identify an additional SRPS gene and further unravel the functional basis for IFT. We perform whole-exome sequencing and identify mutations in a new disease-producing gene, cytoplasmic dynein-2 light intermediate chain 1, DYNC2LI1, segregating with disease in three families. Using primary fibroblasts, we show that DYNC2LI1 is essential for dynein-2 complex stability and that mutations in DYNC2LI1 result in variable length, including hyperelongated, cilia, Hedgehog pathway impairment and ciliary IFT accumulations. The findings in this study expand our understanding of SRPS locus heterogeneity and demonstrate the importance of DYNC2LI1 in dynein-2 complex stability, cilium function, Hedgehog regulation and skeletogenesis.

}, keywords = {Biological Transport, Cilia, Cytoplasmic Dyneins, Cytoskeleton, Female, Fibroblasts, Flagella, Hedgehog Proteins, Humans, Male, Mutation, Pedigree, Short Rib-Polydactyly Syndrome}, issn = {2041-1723}, doi = {10.1038/ncomms8092}, author = {Taylor, S Paige and Dantas, Tiago J and Duran, Ivan and Wu, Sulin and Lachman, Ralph S and Nelson, Stanley F and Cohn, Daniel H and Vallee, Richard B and Krakow, Deborah} }