Abstract
The recent advances in genome sequencing have also led to the discovery of many small ORFs that may encode peptides with secretory signal sequences and receptor-like kinases that may participate in ligand perception. Secreted peptides are, however, often synthesized in the cell as larger precursor peptides, which are biologically inactive and undergo a variety of post-translational modifications and proteolytic processing steps to yield the active peptides. A major challenge in plant functional peptidomics is the development of a systematic methodology to comprehensively identify the mature structures of gene products in terms of proteolytic processing and post-translational modifications. We have developed the efficient purification and identification procedure of secreted peptides contained in plant cell cultures. Here we report the results of peptide analysis contained in various Arabidopsis cell cultures.