title: Craniofacial cartilage morphogenesis requires zebrafish col11a1 activity.
abstract: The zebrafish ortholog of the human COL11A1 gene encoding the cartilage collagen XI proalpha1 chain was characterized to explore its function in developing zebrafish using the morpholino-based knockdown strategy. We showed that its expression in zebrafish is developmentally regulated. A low expression level was detected by real-time PCR during the early stages of development. At 24 hpf, a sharp peak of expression was observed. At that stage, in situ hybridization indicated that col11a1 transcripts are restricted to notochord. At 48 hpf, they were exclusively detected in the craniofacial skeleton, endoskeleton of pectoral fins and in otic vesicles. Collagen XI alpha1-deficient zebrafish embryos developed defects in craniofacial cartilage formation and in notochord morphology. Neural crest specification and mesenchymal condensation occurred normally in morpholino-injected embryos. Col11a1 depletion affected the spatial organization of chondrocytes, the shaping of cartilage elements, and the maturation of chondrocytes to hypertrophy. Knockdown of col11a1 in embryos stimulated the expression of the marker of chondrocyte differentiation col2a1, resulting in the deposit of abnormally thick and sparse fibrils in the cartilage extracellular matrix. The extracellular matrix organization of the perichordal sheath was also altered and led to notochord distortion. The data underscore the importance of collagen XI in the development of a functional cartilage matrix. Moreover, the defects observed in cartilage formation resemble those observed in human chondrodysplasia such as the Stickler/Marshall syndrome. Zebrafish represent a novel reliable vertebrate model for collagen XI collagenopathies.
authors.affiliation: Université de Lyon, Université Lyon 1, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Baas
authors.forename: Maryline
authors.initials: M
authors.lastname: Malbouyres
authors.forename: Zofia
authors.initials: Z
authors.lastname: Haftek-Terreau
authors.forename: Dominique
authors.initials: D
authors.lastname: Le Guellec
authors.forename: Florence
authors.initials: F
authors.lastname: Ruggiero
mesh_terms: D000595:Amino Acid Sequence; D000825:Animal Structures / Q000002:abnormalities / Q000196:embryology / Q000378:metabolism; D000818:Animals; D002356:Cartilage / Q000002:abnormalities / Q000196:embryology* / Q000378:metabolism*; D003001:Cloning, Molecular; D024043:Collagen Type II / Q000235:genetics; D024161:Collagen Type XI / Q000502:physiology*; D019465:Craniofacial Abnormalities / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D016373:DNA, Antisense / Q000235:genetics; D051767:Early Growth Response Protein 2 / Q000235:genetics; D004625:Embryo, Nonmammalian / Q000002:abnormalities / Q000196:embryology / Q000378:metabolism; D015870:Gene Expression / Q000235:genetics; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D006257:Head / Q000002:abnormalities / Q000196:embryology*; D018398:Homeodomain Proteins / Q000235:genetics; D007814:Larva / Q000033:anatomy & histology / Q000254:growth & development / Q000378:metabolism; D008969:Molecular Sequence Data; D009024:Morphogenesis / Q000502:physiology*; D009672:Notochord / Q000002:abnormalities / Q000196:embryology / Q000378:metabolism; D010614:Pharynx / Q000002:abnormalities / Q000196:embryology / Q000378:metabolism; D055758:SOX9 Transcription Factor / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000235:genetics; D015027:Zebrafish / Q000196:embryology* / Q000235:genetics / Q000378:metabolism; D029961:Zebrafish Proteins / Q000235:genetics
chemical_list: D024043:Collagen Type II; D024161:Collagen Type XI; D016373:DNA, Antisense; C088334:Distal-less homeobox proteins; D051767:Early Growth Response Protein 2; D018398:Homeodomain Proteins; D055758:SOX9 Transcription Factor; C504918:Sox9a protein, zebrafish; D014157:Transcription Factors; D029961:Zebrafish Proteins