Dataset Information

L-leucine partially rescues translational and developmental defects associated with zebrafish models of Cornelia de Lange syndrome.

ABSTRACT: Cohesinopathies are human genetic disorders that include Cornelia de Lange syndrome (CdLS) and Roberts syndrome (RBS) and are characterized by defects in limb and craniofacial development as well as mental retardation. The developmental phenotypes of CdLS and other cohesinopathies suggest that mutations in the structure and regulation of the cohesin complex during embryogenesis interfere with gene regulation. In a previous project, we showed that RBS was associated with highly fragmented nucleoli and defects in both ribosome biogenesis and protein translation. l-leucine stimulation of the mTOR pathway partially rescued translation in human RBS cells and development in zebrafish models of RBS. In this study, we investigate protein translation in zebrafish models of CdLS. Our results show that phosphorylation of RPS6 as well as 4E-binding protein 1 (4EBP1) was reduced in nipbla/b, rad21 and smc3-morphant embryos, a pattern indicating reduced translation. Moreover, protein biosynthesis and rRNA production were decreased in the cohesin morphant embryo cells. l-leucine partly rescued protein synthesis and rRNA production in the cohesin morphants and partially restored phosphorylation of RPS6 and 4EBP1. Concomitantly, l-leucine treatment partially improved cohesinopathy embryo development including the formation of craniofacial cartilage. Interestingly, we observed that alpha-ketoisocaproate (?-KIC), which is a keto derivative of leucine, also partially rescued the development of rad21 and nipbla/b morphants by boosting mTOR-dependent translation. In summary, our results suggest that cohesinopathies are caused in part by defective protein synthesis, and stimulation of the mTOR pathway through l-leucine or its metabolite ?-KIC can partially rescue development in zebrafish models for CdLS.

SUBMITTER: Xu B

PROVIDER: S-EPMC4351377 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

L-leucine partially rescues translational and developmental defects associated with zebrafish models of Cornelia de Lange syndrome.

Xu Baoshan B Sowa Nenja N Cardenas Maria E ME Gerton Jennifer L JL

Human molecular genetics 20141106 6

Cohesinopathies are human genetic disorders that include Cornelia de Lange syndrome (CdLS) and Roberts syndrome (RBS) and are characterized by defects in limb and craniofacial development as well as mental retardation. The developmental phenotypes of CdLS and other cohesinopathies suggest that mutations in the structure and regulation of the cohesin complex during embryogenesis interfere with gene regulation. In a previous project, we showed that RBS was associated with highly fragmented nucleol ...[more]

PMID: 25378554

Similar Datasets

Project description:Cornelia de Lange Syndrome (CdLS) is the founding member of a class of multi-organ system birth defect syndromes termed cohesinopathies, named for the chromatin-associated protein complex cohesin, which mediates sister chromatid cohesion. Most cases of CdLS are caused by haploinsufficiency for Nipped-B-like (Nipbl), a highly conserved protein that facilitates cohesin loading. Consistent with recent evidence implicating cohesin and Nipbl in transcriptional regulation, both CdLS cell lines and tissues of Nipbl-deficient mice show changes in the expression of hundreds of genes. Nearly all such changes are modest, however--usually less than 1.5-fold--raising the intriguing possibility that, in CdLS, severe developmental defects result from the collective action of many otherwise innocuous perturbations. As a step toward testing this hypothesis, we developed a model of nipbl-deficiency in zebrafish, an organism in which we can quantitatively investigate the combinatorial effects of gene expression changes. After characterizing the structure and embryonic expression of the two zebrafish nipbl genes, we showed that morpholino knockdown of these genes produces a spectrum of specific heart and gut/visceral organ defects with similarities to those in CdLS. Analysis of nipbl morphants further revealed that, as early as gastrulation, expression of genes involved in endodermal differentiation (sox32, sox17, foxa2, and gata5) and left-right patterning (spaw, lefty2, and dnah9) is altered. Experimental manipulation of the levels of several such genes--using RNA injection or morpholino knockdown--implicated both additive and synergistic interactions in causing observed developmental defects. These findings support the view that birth defects in CdLS arise from collective effects of quantitative changes in gene expression. Interestingly, both the phenotypes and gene expression changes in nipbl morphants differed from those in mutants or morphants for genes encoding cohesin subunits, suggesting that the transcriptional functions of Nipbl cannot be ascribed simply to its role in cohesin loading.

Project description:BackgroundCornelia de Lange (CdLS) is a rare genetic disorder that affects most body systems. Variants in multiple genes including NIPBL and SMC1A, can cause the syndrome. To date, literature on genotype-phenotype associations in individuals with CdLS is extremely limited, although studies suggest some differences in clinical phenotype severity across variants. This study aimed to examine and compare neurobehavioral differences and developmental variability across CdLS genes, specifically NIPBL and SMC1A, and identify genotype-phenotype correlations.Participants and methodsThis patient-reported outcomes study included accessing data from the Coordination of Rare Diseases registry at Sanford. Parents of a total of 26 children/adults with CdLS and a known variant in NIPBL (Mean age = 20.46 years, SD = 11.21) and 12 with a known variant in SMC1A (Mean age = 11.08 years, SD = 9.04) completed a series of questionnaires regarding their child's developmental history. This included attainment of common language and motor milestones, intervention history, and behavior functioning. Developmental history and reported behavior regulation difficulties were compared across variant groups.ResultsOverall, individuals with a pathogenic variant in NIPBL or SMC1A were similarly delayed across motor and language milestones with about 70% not using phrase speech and 30-50% not walking by 5 years of age. However, those with NIPBL variants showed more severity in behavioral phenotype, namely with more repetitive behaviors, tantrums, and withdrawn behaviors. In addition, these individuals were more likely than those with SMC1A variants to demonstrate self-injurious behaviors, and anxiety. Both groups yielded a similar proportion of participants who participated in speech and occupational therapy, however those with SMC1A variants were more likely to engage in physical therapy. Both clinical groups report low rate of communicative or assistive device use despite a large proportion of participants never mastering single word or sentence use.ConclusionsStudy results are consistent with recent investigations highlighting more severe behavioral phenotype, particularly autistic features, anxiety, and behavior regulation challenges, among those with NIPBL variants albeit comparable developmental milestones. Both groups endorsed very elevated attention problems. Findings highlight importance of early interventions, including behavioral health services.

Dataset Information

L-leucine partially rescues translational and developmental defects associated with zebrafish models of Cornelia de Lange syndrome.

Publications

L-leucine partially rescues translational and developmental defects associated with zebrafish models of Cornelia de Lange syndrome.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets