Molecular biomechanics of seed germination in Arabidopsis thaliana and Lepidium sativum

摘要: Seed germination is a key process in world agriculture. For this reason, the capacity of seed to germinate with minimum input from farmers highly desirable, keeping production costs as low possible. The physiological mechanism well known, involving rupture endosperm and testa envelope by expanding embryo, but molecular biomechanical changes underlying are poorly understood. In order answer question how plant developmentally regulates cell wall stiffness associated germination, an innovative biomechanics approach was developed. It combines biophysical, engineering biology approaches. A comparative taken using related species Arabidopsis thaliana Lepidium sativum, former due wealth genomic resources, latter larger size ease use experiments. Environmental scanning electron microscopy imaging revealed that structure intact after protrusion radicle, confirming fact occurs between individual cells. Germination requires targeted separation or/ remodeling. following predictions gene network SeedNet, containing endosperm-specific sub-network cluster 19 (Bassel et al., 2011), specific genes were studied. In localize their expression, promoter::GUS constructs used for DELTA-VPE, SCPL51 DOF2.1, different mutant alleles four transcription factors (athb23, bhlh-115, bee2 dof2.1) screened identify behaviour. DELTA-VPE proven be ABA insensitive. DELTA-VPE GA insensitive expression required GA. Also, could observed 15 minutes imbibition whole endosperm, while showed temporal requiring 18 hours before being all analysed T-DNA lines epistatic relationship ATHB23 DOF 2.1 decreased sensitivity stress like osmotic salt stresses, than wild type. Using nanoindentation, differentiation regions attempted, methodology not sensitive enough. However, elastic modulus values imbibed dry seeds registered. To image internal during micro-CT used, estimating thickness state germinated one. This work enforces knowledge properties endosperm.