PT  - JOURNAL ARTICLE
AU  - N. M. Doll
AU  - S. Royek
AU  - S. Fujita
AU  - S. Okuda
AU  - A. Stintzi
AU  - T. Widiez
AU  - M. Hothorn
AU  - A. Schaller
AU  - N. Geldner
AU  - G. Ingram
TI  - A two-way molecular dialogue between embryo and endosperm required for seed development
AID  - 10.1101/809368
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 809368
4099  - http://biorxiv.org/content/early/2019/10/17/809368.short
4100  - http://biorxiv.org/content/early/2019/10/17/809368.full
AB  - The plant embryonic cuticle is a hydrophobic barrier deposited de novo by the embryo during seed development. At germination it protects the seedling from water loss and is thus critical for survival. Embryonic cuticle formation is controlled by a signaling pathway involving the protease ALE1 and the receptor-like kinases GSO1 and GSO2. We show that a sulfated peptide, TWISTED SEED1 (TWS1) acts as a GSO1/GSO2 ligand. Cuticle surveillance depends on the action of ALE1 which, unlike TWS1 and GSO1/2, is not produced in the embryo but in the neighboring endosperm. Cleavage of an embryo-derived TWS1 precursor by ALE1 releases the active peptide, triggering GSO1/2-dependent cuticle reinforcement in the embryo. A bidirectional molecular dialogue between embryo and endosperm thus safeguards cuticle integrity prior to germination.One Sentence Summary Subtilase-mediated activation of the TWISTED SEED1 peptide provides spatial cues during embryo cuticle integrity monitoring.