Journal
PLANT PHYSIOLOGY
Volume 176, Issue 3, Pages 2040-2051Publisher
OXFORD UNIV PRESS INC
DOI: 10.1104/pp.17.01693
Keywords
-
Categories
Funding
- Grant Agency of Czech Republic [14-27329P, GF16-34887L]
- Czech Ministry of Education [NPUI LO1417]
- Grant Agency of Charles University [GA UK(CZ) 387515]
- European Regional Development Fund
- state budget of the Czech Republic [CZ.1.05/4.1.00/16.0347, CZ.2.16/3.1.00/21515]
Ask authors/readers for more resources
Biogenesis of the plant secondary cell wall involves many important aspects, such as phenolic compound deposition and often silica encrustation. Previously, we demonstrated the importance of the exocyst subunit EXO70H4 for biogenesis of the trichome secondary cell wall, namely for deposition of the autofluorescent and callose-rich cell wall layer. Here, we reveal that EXO70H4driven cell wall biogenesis is constitutively active in the mature trichome, but also can be activated elsewhere upon pathogen attack, giving this study a broader significance with an overlap into phytopathology. To address the specificity of EXO70H4 among the EXO70 family, we complemented the exo70H4-1 mutant by 18 different Arabidopsis (Arabidopsis thaliana) EXO70 paralogs subcloned under the EXO70H4 promoter. Only EXO70H4 had the capacity to rescue the exo70H4-1 trichome phenotype. Callose deposition phenotype of exo70H4-1 mutant is caused by impaired secretion of PMR4, a callose synthase responsible for the synthesis of callose in the trichome. PMR4 colocalizes with EXO70H4 on plasma membrane microdomains that do not develop in the exo70H4-1 mutant. Using energy-dispersive x-ray microanalysis, we show that both EXO70H4- and PMR4-dependent callose deposition in the trichome are essential for cell wall silicification.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available