Wrapper, a novel member of the Ig superfamily, is expressed by midline glia and is required for them to ensheath commissural axons in Drosophila

Neuron. 1998 Nov;21(5):991-1001. doi: 10.1016/s0896-6273(00)80618-2.


The midline glia are specialized, nonneuronal cells at the midline of the Drosophila central nervous system (CNS). During development, the midline glia provide guidance cues for extending axons. At the same time, they migrate and help separate the two axon commissures. They then wrap around and ensheath the commissural axons. In many segments, a few of the glia do not enwrap the axons, and these cells die. The wrapper gene encodes a novel member of the immunoglobulin (Ig) superfamily. Wrapper protein is expressed specifically on the surface of midline glia. In wrapper mutant embryos, the midline glia express their normal guidance cues and migrate normally. However, they do not ensheath the commissural axons, and as a result, the glia die. In the absence of Wrapper, the two axon commissures are not properly separated.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Axons / physiology*
  • Drosophila / embryology
  • Drosophila / genetics
  • Drosophila Proteins*
  • Gene Expression Regulation, Developmental
  • Immunoglobulins / chemistry*
  • Immunoglobulins / genetics
  • Insect Proteins / chemistry*
  • Insect Proteins / genetics
  • Molecular Sequence Data
  • Multigene Family
  • Mutagenesis
  • Nerve Tissue Proteins / biosynthesis*
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / physiology
  • Neuroglia / metabolism*
  • Sequence Homology, Amino Acid


  • Drosophila Proteins
  • Immunoglobulins
  • Insect Proteins
  • Nerve Tissue Proteins
  • wrapper protein, Drosophila

Associated data

  • GENBANK/AF134113