************************************************************ * Cereal trypsin/alpha-amylase inhibitors family signature * ************************************************************ The seeds of cereals contain numerous serine proteases and alpha-amylase inhibitors. These inhibitors can be grouped into families based on structural similarities. The cereal trypsin/alpha-amylase inhibitor family [1,2] consists of proteins of about 120 amino acids which contain 10 cysteine residues, all of which are involved in disulfide bonds. Some of these inhibitors are specific to trypsin, others to alpha-amylase, and a few are bifunctional. The schematic representation of the structure of these inhibitors is shown below: +----------------------------+ +----------+| +-+ | *******|**** || | | | xxCxxxxxxCxxxCxxxxxxCCxxxCxCxxxxxxxxxxxxxCxxxxxxxxCxxxxxxxCxxxx | | | | | +---------------------------+ | +-------------------------------------------------------+ 'C': conserved cysteine involved in a disulfide bond. '*': position of the pattern. This family of proteins also includes a number of seed allergenic protein from rice [3]. -Consensus pattern: C-x(10)-L-x(2)-C-x(2)-[LIVMFY](2)-x(3,4)-C [The three C's are involved in disulfide bonds] -Sequences known to belong to this class detected by the pattern: ALL. -Other sequence(s) detected in SWISS-PROT: Drosophila Notch, human uromodulin, human complement receptor 2 and Trypanosoma leucine repeat protein ESAG-8. -Last update: June 1994 / Text revised. [ 1] Gautier M.-F., Alary R., Joudirer P. Plant Mol. Biol. 14:313-322(1990). [ 2] Garcia-Olmedo F., Salcedo G., Sanchez-Monge R., Gomez L., Royo J., Carbonero P. (In) Oxford Surveys of Plant Molecular and Cell Biology, Miflin B., Ed., vol. 4, pp. 275-334, Oxford University Press, Oxford, (1987). [ 3] Adachi T., Izumi H., Yamada T., Tanaka K., Takeuchi S., Nakamura R., Matsuda T. Plant Mol. Biol. 21:239-248(1993).