Post-translational maturation of IDA, a peptide signal controlling floral organ abscission in Arabidopsis.

Publication Type

Journal contribution (peer reviewed)

Authors

Stührwohldt, N., Hohl, M., Schardon, K., Stintzi, A., Schaller, A.

Year of publication

2018

Published in

Commun. Integr. Biol.

DOI

10.1080/19420889.2017.1395119

Page (from - to)

e1395119

The abscission of sepals, petals and stamens in Arabidopsis flowers is controlled by a peptide signal called IDA (Inflorescence Deficient in Abscission). IDA belongs to the large group of small post-translationally modified signaling peptides that are synthesized as larger precursors and require proteolytic processing and specific side chain modifications for signal biogenesis. Using tissue-specific expression of proteinase inhibitors as a novel approach for loss-of-function analysis, we recently identified the peptidases responsible for IDA maturation within the large family of subtilisin-like proteinases (subtilases; SBTs). Further biochemical and physiological assays identified three SBTs (AtSBT5.2, AtSBT4.12, AtSBT4.13) that cleave the IDA precursor to generate the N-terminus of the mature peptide. The C-terminal processing enzyme(s) remain(s) to be identified. While proline hydroxylation was suggested as additional post-translational modification required for IDA maturation, hydroxylated and non-hydroxylated IDA peptides were found to be equally active in bioassays for abscission.