Nature 376, 420 - 423 (03 August 2002); doi:10.1038/376420a0

Hox genes and the diversification of insect and crustacean body plans

Michalis Averof & Michael Akam

Wellcome/CRC Institute, Tennis Court Road, Cambridge CB2 1QR, and Department of Genetics, University of Cambridge, Cambridge, UK

CRUSTACEANS and insects share a common origin of segmentation^1,2, but the specialization of trunk segments appears to have arisen independently in insects and various crustacean subgroups^3,4. Such macroevolutionary changes in body architecture may be investigated by comparative studies of conserved genetic markers^5á¤-7. The Hox genes are well suited for this purpose, as they determine positional identity along the body axis in a wide range of animals^8á¤-10. Here we examine the expression of four Hox genes in the branchiopod crustacean Artemia frandscana, and compare this with Hox expression patterns from insects. In Artemia the three á¤~trunkᤙ genes Antp, Ubx and abdA are expressed in largely overlapping domains in the uniform thoracic region, whereas in insects they specify distinct segment types within the thorax and abdomen. Our comparisons suggest a multistep process for the diversification of these Hox gene functions, involving early differences in tissue specificity and the later acquisition of a role in defining segmental differences within the trunk. We propose that the branchiopod thorax may be homologous to the entire pregenital (thoracic and abdominal) region of the insect trunk.

References

1.	Dohle, W. & Scholtz, G. Development 104 (suppl.), 147−160 (1988). | PubMed |
2.	Patel, N. H., Kornberg, T. B. & Goodman, C. S. Development 107, 201−212 (1989). | PubMed | ISI | ChemPort |
3.	Calman, W. T. Crustacea (Black, London, 1909).
4.	Walossek, D. Fossils and Strata 32, 1−202 (1993).
5.	Averof, M. & Akam, M. Curr. Biol. 3, 73−78 (1993). | Article | PubMed | ISI | ChemPort |
6.	Slack, J. M. W., Holland, P. W. H. & Graham, C. F. Nature 361, 490−492 (1993). | Article | PubMed | ISI | ChemPort |
7.	Arendt, D. & Nubler-Jung, K. Nature 371, 26 (1994). | Article | PubMed | ISI | ChemPort |
8.	Lewis, E. B. Nature 276, 567−570 (1978).
9.	Akam, M., Dawson, I. & Tear, G. Development 104 (suppl.), 123−133 (1988).
10.	McGinnis, W. & Krumlauf, R. Cell 68, 283−302 (1992). | Article | PubMed | ISI | ChemPort |
11.	Akam, M. et al. Development 120 (suppl.), 209−215 (1994). | PubMed | ISI | ChemPort |
12.	Andersen, D. T. Aust. J. Zool. 15, 47−91 (1967).
13.	Manzanares, M., Marco, R. & Garesse, R. Development 118, 1209−1219 (1993). | PubMed | ChemPort |
14.	Kelsh, R., Weinzierl, R. O. J., White, R. A. H. & Akam, M. Devl Genet. 15, 19−31 (1994). | ChemPort |
15.	Warren, R. W., Nagy, L., Selegue, J., Bates, J. & Carroll, S. Nature 372, 458−461 (1994). | Article | PubMed | ISI | ChemPort |
16.	Snodgrass, R. E. Comparative Studies on the Head or Mandibulate Arthropods (Comstock, New York, 1951).
17.	Mahaffey, J. W., Diederich, R. J. & Kaufman, T. C. Development 105, 167−174 (1989). | PubMed | ChemPort |
18.	Beeman, R. W., Stuart, J. J., Brown, S. J. & Denell, R. E. BioEssays 15, 439−444 (1993). | Article | PubMed | ChemPort |
19.	Ueno, K., Hui, C.-C. Fukuta, M. & Suzuki, Y. Development 114, 555−563 (1992). | PubMed | ISI | ChemPort |
20.	Karch, F., Bender, W. & Weiffenbach, B. Genes Dev. 4, 1573−1588 (1990). | PubMed | ISI | ChemPort |
21.	Tear, G., Akam, M. & Martinez-Arias, A. Development 110, 915−925 (1990). | PubMed | ChemPort |
22.	Li, X. & Noll, M. Nature 367, 83−87 (1994). | Article | PubMed | ISI | ChemPort |
23.	Rothe, M., Pehl, M., Taubert, H. & Jackle, H. Nature 359, 156−159 (1992). | Article | PubMed | ChemPort |
24.	Castelli-Gair, J., Greig, S., Micklem, G. & Akam, M. Development 120, 1983−1995 (1994). | PubMed | ChemPort |
25.	Vachon, G. et al. Cell 71, 437−450 (1992). | Article | PubMed | ISI | ChemPort |
26.	Jurgens, G. & Hartenstein, V. in The Development of Drosophila melanogaster (eds Bate, M. & Martinez-Arias, A.) 687−746 (Cold Spring Harbor Laboratory Press, 1993).
27.	Scourfield, D. J. Phil. Trans. R. Soc. B214, 153−187 (1926).
28.	Riek, E. F. Rec. S. Aust. Mus. 27, 313−321 (1968).
29.	McNamara, K. J. & Trewin, N. H. Palaeontology 36, 319−335 (1993). | ISI |
30.	Dohle, W. Myriapoda and the Ancestry of Insects (Manchester Polytechnic, Manchester, 1988).