A novel myosin-like protein (myocilin) expressed in the connecting cilium of the photoreceptor: molecular cloning, tissue expression, and chromosomal mapping

Genomics. 1997 May 1;41(3):360-9. doi: 10.1006/geno.1997.4682.


We have isolated a human cDNA clone encoding a novel acidic protein of MW 55,000 that we designated "myocilin" since it has homology to myosin and is localized preferentially in the ciliary rootlet and basal body of the connecting cilium of photoreceptor cells. The deduced amino acid sequence of human myocilin showed significant homologies with nonmuscle myosin of Dictyostelium discoideum in the N-terminal region and also with olfactomedin of bullfrog in the C-terminal region. Myocilin contained a leucine zipper-like motif similar to that seen in kinectin and other cytoskeletal proteins. These findings suggest that myocilin is a novel cytoskeletal protein involved in the morphogenesis of ciliated neuroepithelium such as photoreceptor cells. The myocilin gene (MYOC) was mapped to human chromosome 1q23-q24 by fluorescence in situ hybridization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Chromosome Mapping
  • Chromosomes, Human, Pair 1 / genetics
  • Cloning, Molecular
  • Cytoskeletal Proteins / genetics*
  • DNA Primers / genetics
  • DNA, Complementary / genetics
  • Dictyostelium / genetics
  • Extracellular Matrix Proteins / genetics
  • Eye Proteins / genetics*
  • Gene Expression
  • Glycoproteins / genetics
  • Humans
  • In Situ Hybridization, Fluorescence
  • Mice
  • Molecular Sequence Data
  • Myosins / genetics
  • Photoreceptor Cells / metabolism*
  • Photoreceptor Cells / ultrastructure
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Rana catesbeiana
  • Sequence Homology, Amino Acid
  • Swine
  • Tissue Distribution


  • Cytoskeletal Proteins
  • DNA Primers
  • DNA, Complementary
  • Extracellular Matrix Proteins
  • Eye Proteins
  • Glycoproteins
  • RNA, Messenger
  • olfactomedin
  • trabecular meshwork-induced glucocorticoid response protein
  • Myosins

Associated data

  • GENBANK/AB006686
  • GENBANK/AB006687
  • GENBANK/AB006688
  • GENBANK/D88214