The KMT2D Kabuki syndrome histone methylase controls neural crest cell differentiation and facial morphology

Development. 2020 Jul 17;147(21):dev187997. doi: 10.1242/dev.187997.

Abstract

Kabuki syndrome (KS) is a congenital craniofacial disorder resulting from mutations in the KMT2D histone methylase (KS1) or the UTX histone demethylase (KS2). With small cohorts of KS2 patients, it is not clear whether differences exist in clinical manifestations relative to KS1. We mutated KMT2D in neural crest cells (NCCs) to study cellular and molecular functions in craniofacial development with respect to UTX. Similar to UTX, KMT2D NCC knockout mice demonstrate hypoplasia with reductions in frontonasal bone lengths. We have traced the onset of KMT2D and UTX mutant NCC frontal dysfunction to a stage of altered osteochondral progenitor differentiation. KMT2D NCC loss-of-function does exhibit unique phenotypes distinct from UTX mutation, including fully penetrant cleft palate, mandible hypoplasia and deficits in cranial base ossification. KMT2D mutant NCCs lead to defective secondary palatal shelf elevation with reduced expression of extracellular matrix components. KMT2D mutant chondrocytes in the cranial base fail to properly differentiate, leading to defective endochondral ossification. We conclude that KMT2D is required for appropriate cranial NCC differentiation and KMT2D-specific phenotypes may underlie differences between Kabuki syndrome subtypes.

Keywords: Craniofacial; Histone methylation; KMT2D; Kabuki syndrome; MLL4; Neural crest.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abnormalities, Multiple / enzymology*
  • Abnormalities, Multiple / pathology*
  • Alleles
  • Animals
  • Cell Differentiation*
  • Cell Lineage
  • Cell Movement
  • Chondrocytes / pathology
  • Face / abnormalities*
  • Face / pathology
  • Hematologic Diseases / enzymology*
  • Hematologic Diseases / pathology*
  • Histone-Lysine N-Methyltransferase / metabolism*
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Morphogenesis
  • Mutation / genetics
  • Myeloid-Lymphoid Leukemia Protein / metabolism*
  • Neural Crest / enzymology*
  • Neural Crest / pathology*
  • Osteogenesis
  • Palate / embryology
  • Palate / metabolism
  • Palate / pathology
  • Phenotype
  • Skull / pathology
  • Vestibular Diseases / enzymology*
  • Vestibular Diseases / pathology*

Substances

  • Myeloid-Lymphoid Leukemia Protein
  • Histone-Lysine N-Methyltransferase
  • Kmt2b protein, mouse

Supplementary concepts

  • Kabuki syndrome