Tissue and stage-specific expression of the Tolls in Drosophila embryos

Gene Expr Patterns. 2002 Dec;2(3-4):311-7. doi: 10.1016/s1567-133x(02)00020-0.


The Drosophila transmembrane receptor Toll plays a key role in specifying the dorsoventral axis of the embryo. At later stages of development, it controls the immune response of the fly to fungal and Gram-positive bacterial infections. The Drosophila genome has a total of nine Toll-like genes, including the previously characterized Toll (Toll-1) and 18-wheeler (Toll-2). Here we describe the embryonic expression patterns of the seven Toll-like genes Toll-3 through Toll-9. We find that these genes have distinct expression domains and that their expression is dynamically changing throughout embryonic development. This complex and tissue-specific regulation of Toll-like gene expression strongly suggests a role in embryonic development for most Drosophila Tolls. The evolving picture on the Toll family members in Drosophila contrasts with that of mammalian Toll-like receptors, which are predominantly expressed in immune responsive cells where their activation occurs via microbial structural determinants.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Blotting, Northern
  • Drosophila / embryology*
  • Drosophila / immunology
  • Drosophila / metabolism*
  • Drosophila Proteins / genetics*
  • Drosophila Proteins / immunology
  • Drosophila Proteins / metabolism
  • Gene Expression Profiling
  • Larva / immunology
  • Multigene Family*
  • Receptors, Cell Surface / genetics*
  • Receptors, Cell Surface / immunology
  • Receptors, Cell Surface / metabolism
  • Toll-Like Receptors


  • Drosophila Proteins
  • Receptors, Cell Surface
  • Tl protein, Drosophila
  • Toll-Like Receptors