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Am J Hum Genet
2015 Sep 03;973:378-88. doi: 10.1016/j.ajhg.2015.07.007.
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Gain-of-Function Mutations in ZIC1 Are Associated with Coronal Craniosynostosis and Learning Disability.
Twigg SR
,
Forecki J
,
Goos JA
,
Richardson IC
,
Hoogeboom AJ
,
van den Ouweland AM
,
Swagemakers SM
,
Lequin MH
,
Van Antwerp D
,
McGowan SJ
,
Westbury I
,
Miller KA
,
Wall SA
,
WGS500 Consortium
,
van der Spek PJ
,
Mathijssen IM
,
Pauws E
,
Merzdorf CS
,
Wilkie AO
.
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Human ZIC1 (zinc finger protein of cerebellum 1), one of five homologs of the Drosophila pair-rule gene odd-paired, encodes a transcription factor previously implicated in vertebrate brain development. Heterozygous deletions of ZIC1 and its nearby paralog ZIC4 on chromosome 3q25.1 are associated with Dandy-Walker malformation of the cerebellum, and loss of the orthologous Zic1 gene in the mouse causes cerebellar hypoplasia and vertebral defects. We describe individuals from five families with heterozygous mutations located in the final (third) exon of ZIC1 (encoding four nonsense and one missense change) who have a distinct phenotype in which severe craniosynostosis, specifically involving the coronal sutures, and variable learning disability are the most characteristic features. The location of the nonsense mutations predicts escape of mutant ZIC1 transcripts from nonsense-mediated decay, which was confirmed in a cell line from an affected individual. Both nonsense and missense mutations are associated with altered and/or enhanced expression of a target gene, engrailed-2, in a Xenopus embryo assay. Analysis of mouse embryos revealed a localized domain of Zic1 expression at embryonic days 11.5-12.5 in a region overlapping the supraorbital regulatory center, which patterns the coronal suture. We conclude that the human mutations uncover a previously unsuspected role for Zic1 in early cranial suture development, potentially by regulating engrailed 1, which was previously shown to be critical for positioning of the murine coronal suture. The diagnosis of a ZIC1 mutation has significant implications for prognosis and we recommend genetic testing when common causes of coronal synostosis have been excluded.
Figure 1. Clinical and Radiological Phenotype of Individuals with ZIC1 Mutations(A) Subject 1, age 7 weeks (left) and 8 years (right).(B) Subject 2, age 23 years.(C) Subject 3, age 5 months.(D) CT head scan of subject 3 (age 5 months) showing bicoronal synostosis, a large wormian bone (arrow) in the position of the anterior fontanelle, and an ossification defect in the sagittal suture (arrowhead).(E) Subject 4, age 7 months.(F) CT head scan of subject 4 (age 2.5 months). Note asymmetric skull shape associated with bilateral coronal and right lambdoid suture fusion (arrow). Sections of the metopic and sagittal sutures remain widely patent (arrowheads).(G) MRI brain scan (T2 image) of subject 4, age 16 months. Note short, broad corpus callosum, peaked tentorium cerebelli (arrow), and hypoplasia of the pons (arrowhead), cerebellar vermis, and cerebellar hemispheres.(H) Pedigree of family 5.(I) Subject 5:III.6, age 2 months.(J) MRI brain scan (T2 image) of subject 5:III.6, age 13 years. Abnormal features show a similar pattern to those present in subject 4.
Figure 2. Molecular Genetic Analysis of Individuals with ZIC1 Mutations(A) Cartoon showing exon organization (white boxes denote non-coding regions) and previously identified conserved domains (Zic opa conserved motif [ZOC], zinc finger N-flanking conserved region [ZF-NC], and five zinc fingers [1â5, blue boxes]) of human ZIC1.16 Also indicated is the C-terminal NEWYV motif conserved in all family members except ZIC4. Above the cartoon are the positions of the five independent ZIC1 mutations described in this report, and dideoxy-sequence traces showing comparison of normal sequence (above) and mutant sequence (below). Note, in the case of subject 3, the mutation was not evident in the DNA sample (sourced from scalp fibroblasts; not shown) originally analyzed; however, in the exome sequence of DNA sourced from blood of the same individual, 63 of 183 (34%) reads showed the c.1204G>T mutation, which is also readily apparent on the dideoxy sequence. The relative heights of mutant and wild-type peaks differ between samples from subject 3 and subject 2, who is constitutionally heterozygous for the identical mutation, corroborating that in subject 3 the mutation is present in high-level mosaic state.(B) Agarose gel analysis of ZIC1 cDNA obtained from RNA extracted from scalp fibroblasts of subject 1 and digested with BfaI. The fragments yielded by digestion of the mutant allele are indicated with asterisks.(C) Amino acid sequence encoded by 3â²-terminal exon of ZIC1 and comparison with the paralogous human proteins ZIC2-ZIC5, showing conservation including the NEWYV motif (bracket). The end of the fifth zinc finger (Zn5) is shown above the sequence, as are the positions of the four different pathogenic variants (red symbols) (triangle, nonsense; circle, missense) identified in this study. The positions at which the Xenopus constructs zic1ÎC2 and zic1ÎC are truncated, relative to the human sequence, are indicated by blue arrows (note zic1ÎC2 is equivalent to p.Gln389â). Additional human constructs tested in the Xenopus assay are indicated by green symbols.
Figure 3. Analysis of Consequences of ZIC1 Mutations in Xenopus Embryos(A) Cartoon showing the structure and nomenclature of the cDNA constructs used in the experiment. The five zinc finger domains are highlighted in blue.(B) Xenopus en-2 expression after microinjection of ZIC1 construct RNA (right side of each embryo). Arrows indicate widened, increased, or shifted en-2 expression in three representative embryos.(C) Quantification of effects of ZIC1 mutations on en-2 expression. The numbers of embryos used in each experiment are indicated in parentheses. Statistical comparisons between full-length Xenopus zic1 and human ZIC1 and between ZIC1 and ZIC1-p.Glu299â were not significant (NS), whereas comparisons between all other mutants and corresponding full-length constructs were highly significant (p < 10â8).
Figure 4. Expression of Zic1 in E11.5âE12.5 Mouse Embryos Analyzed by RNA In Situ Hybridization and Comparison with En1Panels show comparison of Zic1 (A, B) and En1 (C, D) expression at E11.5 (A, C) and E12.5 (B, D). In each case the top panel shows the whole embryo and plane of sections 1, 2, and 3, which are illustrated in the three respective lower panels (e, eye; t, telencephalon; d, diencephalon; m, mesencephalon; f, forebrain; circles indicate relative position of the eye). Note strong expression of Zic1 in supra-orbital region (open arrow) at E11.5; other areas of expression are midbrain-hindbrain boundary (closed arrow), neural tube, and limbmesenchyme (A). At E12.5 Zic1 expression is seen mainly in the cephalic mesenchyme, just posterior to the eye (B). By comparison, at E11.5 the expression of En1 expression is relatively weak in the supraorbital region (stronger expression is seen in the apical ectodermal ridge of the limb and in the somitic mesoderm). By E12.5 En1 expression has increased in the cephalic mesoderm.
Ali,
Zinc fingers of the cerebellum (Zic): transcription factors and co-factors.
2012, Pubmed
Ali,
Zinc fingers of the cerebellum (Zic): transcription factors and co-factors.
2012,
Pubmed
Aruga,
Mouse Zic1 is involved in cerebellar development.
1998,
Pubmed
Aruga,
Zic1 regulates the patterning of vertebral arches in cooperation with Gli3.
1999,
Pubmed
,
Xenbase
Aruga,
A wide-range phylogenetic analysis of Zic proteins: implications for correlations between protein structure conservation and body plan complexity.
2006,
Pubmed
Benedyk,
odd-paired: a zinc finger pair-rule protein required for the timely activation of engrailed and wingless in Drosophila embryos.
1994,
Pubmed
Blank,
Multiple developmental programs are altered by loss of Zic1 and Zic4 to cause Dandy-Walker malformation cerebellar pathogenesis.
2011,
Pubmed
Braddock,
Sagittal craniosynostosis, Dandy-Walker malformation, and hydrocephalus: a unique multiple malformation syndrome.
1993,
Pubmed
Brivanlou,
Expression of an engrailed-related protein is induced in the anterior neural ectoderm of early Xenopus embryos.
1989,
Pubmed
,
Xenbase
Brown,
In vitro analysis of partial loss-of-function ZIC2 mutations in holoprosencephaly: alanine tract expansion modulates DNA binding and transactivation.
2005,
Pubmed
Brown,
Holoprosencephaly due to mutations in ZIC2, a homologue of Drosophila odd-paired.
1998,
Pubmed
Carnevali,
Computational techniques for human genome resequencing using mated gapped reads.
2012,
Pubmed
Chen,
Multiple calvarial defects in lmx1b mutant mice.
1998,
Pubmed
Cowan,
Genetic and functional analyses of ZIC3 variants in congenital heart disease.
2014,
Pubmed
Deckelbaum,
Regulation of cranial morphogenesis and cell fate at the neural crest-mesoderm boundary by engrailed 1.
2012,
Pubmed
Deckelbaum,
The homeoprotein engrailed 1 has pleiotropic functions in calvarial intramembranous bone formation and remodeling.
2006,
Pubmed
DiNardo,
Establishment and refinement of segmental pattern in the Drosophila embryo: spatial control of engrailed expression by pair-rule genes.
1987,
Pubmed
Dreyer,
Mutations in LMX1B cause abnormal skeletal patterning and renal dysplasia in nail patella syndrome.
1998,
Pubmed
Drmanac,
Human genome sequencing using unchained base reads on self-assembling DNA nanoarrays.
2010,
Pubmed
Eley,
Raised intracranial pressure is frequent in untreated nonsyndromic unicoronal synostosis and does not correlate with severity of phenotypic features.
2012,
Pubmed
Ferraris,
Dandy-Walker malformation and Wisconsin syndrome: novel cases add further insight into the genotype-phenotype correlations of 3q23q25 deletions.
2013,
Pubmed
Gaston-Massuet,
Zic4, a zinc-finger transcription factor, is expressed in the developing mouse nervous system.
2005,
Pubmed
Gebbia,
X-linked situs abnormalities result from mutations in ZIC3.
1997,
Pubmed
Grinberg,
Heterozygous deletion of the linked genes ZIC1 and ZIC4 is involved in Dandy-Walker malformation.
2004,
Pubmed
Hajihosseini,
Evidence that Fgf10 contributes to the skeletal and visceral defects of an Apert syndrome mouse model.
2009,
Pubmed
Harland,
In situ hybridization: an improved whole-mount method for Xenopus embryos.
1991,
Pubmed
,
Xenbase
Holmes,
Early onset of craniosynostosis in an Apert mouse model reveals critical features of this pathology.
2009,
Pubmed
Jiang,
Tissue origins and interactions in the mammalian skull vault.
2002,
Pubmed
Johnson,
Craniosynostosis.
2011,
Pubmed
Khajavi,
Nonsense-mediated mRNA decay modulates clinical outcome of genetic disease.
2006,
Pubmed
Kolm,
Regulation of the Xenopus labial homeodomain genes, HoxA1 and HoxD1: activation by retinoids and peptide growth factors.
1995,
Pubmed
,
Xenbase
Kuo,
Opl: a zinc finger protein that regulates neural determination and patterning in Xenopus.
1998,
Pubmed
,
Xenbase
Lajeunie,
Genetic study of nonsyndromic coronal craniosynostosis.
1995,
Pubmed
Li,
The Xfeb gene is directly upregulated by Zic1 during early neural development.
2006,
Pubmed
,
Xenbase
Lunter,
Stampy: a statistical algorithm for sensitive and fast mapping of Illumina sequence reads.
2011,
Pubmed
Merrill,
Cell mixing at a neural crest-mesoderm boundary and deficient ephrin-Eph signaling in the pathogenesis of craniosynostosis.
2006,
Pubmed
Merzdorf,
Emerging roles for zic genes in early development.
2007,
Pubmed
,
Xenbase
Merzdorf,
The zic1 gene is an activator of Wnt signaling.
2006,
Pubmed
,
Xenbase
Milet,
Pax3 and Zic1 drive induction and differentiation of multipotent, migratory, and functional neural crest in Xenopus embryos.
2013,
Pubmed
,
Xenbase
Nagai,
The expression of the mouse Zic1, Zic2, and Zic3 gene suggests an essential role for Zic genes in body pattern formation.
1997,
Pubmed
Plouhinec,
Pax3 and Zic1 trigger the early neural crest gene regulatory network by the direct activation of multiple key neural crest specifiers.
2014,
Pubmed
,
Xenbase
Rimmer,
Integrating mapping-, assembly- and haplotype-based approaches for calling variants in clinical sequencing applications.
2014,
Pubmed
Sharma,
Mutations in TCF12, encoding a basic helix-loop-helix partner of TWIST1, are a frequent cause of coronal craniosynostosis.
2013,
Pubmed
Sive,
Progressive determination during formation of the anteroposterior axis in Xenopus laevis.
1989,
Pubmed
,
Xenbase
Taylor,
Factors influencing success of clinical genome sequencing across a broad spectrum of disorders.
2015,
Pubmed
Ting,
EphA4 as an effector of Twist1 in the guidance of osteogenic precursor cells during calvarial bone growth and in craniosynostosis.
2009,
Pubmed
Twigg,
A Genetic-Pathophysiological Framework for Craniosynostosis.
2015,
Pubmed
Wilkie,
Prevalence and complications of single-gene and chromosomal disorders in craniosynostosis.
2010,
Pubmed
Wurst,
Multiple developmental defects in Engrailed-1 mutant mice: an early mid-hindbrain deletion and patterning defects in forelimbs and sternum.
1994,
Pubmed
Yoshida,
Cell lineage in mammalian craniofacial mesenchyme.
2008,
Pubmed