Spalt Major Controls the Development of the Notum and of Wing Hinge Primordia of the Drosophila Melanogaster Wing Imaginal Disc

Dev Biol. 2009 May 15;329(2):315-26. doi: 10.1016/j.ydbio.2009.03.006. Epub 2009 Mar 17.


The Drosophila wing and the dorsal thorax develop from primordia within the wing imaginal disc. Here we show that spalt major (salm) is expressed within the presumptive dorsal body wall primordium early in wing disc development to specify notum and wing hinge tissue. Upon ectopic salm expression, dorsally located second leg disc cells develop notum and wing hinge tissue instead of sternopleural tissue. Similarly, by salm over-expression within the wing disc, wing blade formation is suppressed and a mirror-image duplication of the notum and wing hinge is formed. In large dorsal clones, which lack salm and its neighboring paralogue spalt related (salr), the cells of the notum primordium do not grow; these dorsal cells are not specified as notum, hence no notum outgrowth develops. These results suggest that the zinc finger factors encoded by the salm/salr complex play important roles in defining cells of the early wing disc as dorsal body wall cells, which develop into a large dorsal body wall territory and form mesonotum and some wing hinge tissue, and in delimiting the wing primordium. We also find that salm activity is down-regulated by its own product and by that of the Pax gene eyegone.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Drosophila Proteins / genetics
  • Drosophila Proteins / physiology*
  • Drosophila melanogaster / embryology*
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / physiology*
  • Transcription Factors / genetics
  • Transcription Factors / physiology*
  • Wings, Animal / embryology*


  • Drosophila Proteins
  • Homeodomain Proteins
  • Transcription Factors
  • salm protein, Drosophila