Biologia, Bratislava, 57/Suppl. 11: 181-189, 2002.
ISSN 0006-3088 (Biologia).
Jean-Luc Da Lage1*, Alain Van Wormhoudt2 & Marie-Louise Cariou1
1 UPR 9034 Populations, génétique et évolution, CNRS, 91198 Gif sur Yvette cedex, France; tel: ++ 33 1 69 82 37 27, fax: ++ 33 1 69 07 04 21, e-mail: email@example.com
2 Station de Biologie marine, Collège de France et Muséum National d’Histoire Naturelle, 29900 Concarneau, France
* corresponding author
Received: October 4, 2001 / Accepted: February 12, 2002
Many living organisms show a tendency to have multiple amylase genes. It is also true in animals. In Drosophilids, the number of Amy copies varies from two to at least seven, including the divergent paralog Amyrel. Comparisons between copies show that the divergence, the gene arrangement and the intron/exon structure are variable among copies within species. In addition, there are often differential expressions of the different copies. A survey of a number of animal Amy sequences shows a high level of protein variability. The inferred protein sequences suggest some evolutionary events which could have adaptative or functional significance, such as the loss or gain of some amino acid stretches: a motif of nine aminoacids has been found in some species but not in others, independently from the phylogenetic relationships. Also, additional cysteines may create new disulfide bridges in some amylases.
Key words: intron, disulfide bridge, gene duplication, flexible loop.