First published online August 4, 2003
Development 130, e1804 (2003)
Copyright © 2003 The Company of Biologists Limited
Proneural gene evolution
Because the achaete-scute (ac/sc) genes seem to initiate
nervous system development in all arthropods, knowing how their number and
function varies between Arthropoda species should provide insights into the
evolution of nervous system development in insects. On
p. 4373, Wheeler et
al. describe the ac/sc genes of the red flour beetle (Tribolium
castaneum), which diverged from Drosophila
300 million
years ago. Both species encode a single neural precursor gene -
asense - which is expressed in all neural precursors. However,
whereas Drosophila encodes three proneural genes (achaete,
scute and lethal of scute), which promote neural precursor
formation, Tribolium encodes a single proneural gene -
achaete-scute homologue (Tc-ASH). Tc-ASH alone can
promote neural precursor formation from ectodermal cells, but unlike
achaete and scute, it plays no apparent role in the fate
specification of individual neural precursors, hinting at a recent
evolutionary specialisation in the Drosophila lineage.
Related articles in Development:
- The expression and function of the achaete-scute genes in Tribolium castaneum reveals conservation and variation in neural pattern formation and cell fate specification
- Scott R. Wheeler, Michelle L. Carrico, Beth A. Wilson, Susan J. Brown, and James B. Skeath
Development 2003 130: 4373-4381.
[Abstract]
[Full Text]