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 EXO70H4-driven 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.

Department of Experimental Plant Biology Faculty of Sciences Charles University Prague Czech Republic

Department of Experimental Plant Biology Faculty of Sciences Charles University Prague Czech Republic Institute of Experimental Botany Academy of Sciences of the Czech Republic Prague Czech Republic

Institute of Scientific Instruments of the Academy of Sciences of the Czech Republic Brno Czech Republic

000      

00000naa a2200000 a 4500

001      

bmc19012948

003      

CZ-PrNML

005      

20190405100543.0

007      

ta

008      

190405s2018 xxu f 000 0|eng||

009      

AR

024    7_

$a 10.1104/pp.17.01693 $2 doi

035    __

$a (PubMed)29301954

040    __

$a ABA008 $b cze $d ABA008 $e AACR2

041    0_

$a eng

044    __

$a xxu

100    1_

$a Kulich, Ivan $u Department of Experimental Plant Biology, Faculty of Sciences, Charles University, Prague, Czech Republic kulich@natur.cuni.cz.

245    10

$a Exocyst Subunit EXO70H4 Has a Specific Role in Callose Synthase Secretion and Silica Accumulation / $c I. Kulich, Z. Vojtíková, P. Sabol, J. Ortmannová, V. Neděla, E. Tihlaříková, V. Žárský,

520    9_

$a 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 EXO70H4-driven 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.

650    _2

$a Arabidopsis $x účinky léků $x genetika $x metabolismus $7 D017360

650    _2

$a proteiny huseníčku $x chemie $x metabolismus $7 D029681

650    _2

$a buněčná membrána $x účinky léků $x metabolismus $7 D002462

650    _2

$a buněčná stěna $x účinky léků $x metabolismus $7 D002473

650    _2

$a flagelin $x farmakologie $7 D005408

650    _2

$a regulace genové exprese u rostlin $x účinky léků $7 D018506

650    _2

$a glukany $7 D005936

650    _2

$a glukosyltransferasy $x metabolismus $7 D005964

650    _2

$a mutace $x genetika $7 D009154

650    _2

$a fenotyp $7 D010641

650    _2

$a epidermis rostlin $x cytologie $x účinky léků $x metabolismus $7 D019441

650    _2

$a proteinové domény $7 D000072417

650    _2

$a podjednotky proteinů $x chemie $x metabolismus $7 D021122

650    _2

$a oxid křemičitý $x metabolismus $7 D012822

650    _2

$a trichomy $x metabolismus $7 D064201

650    _2

$a upregulace $x účinky léků $7 D015854

650    _2

$a vezikulární transportní proteiny $x chemie $x metabolismus $7 D033921

655    _2

$a časopisecké články $7 D016428

655    _2

$a práce podpořená grantem $7 D013485

700    1_

$a Vojtíková, Zdeňka $u Department of Experimental Plant Biology, Faculty of Sciences, Charles University, Prague, Czech Republic.

700    1_

$a Sabol, Peter $u Department of Experimental Plant Biology, Faculty of Sciences, Charles University, Prague, Czech Republic.

700    1_

$a Ortmannová, Jitka $u Department of Experimental Plant Biology, Faculty of Sciences, Charles University, Prague, Czech Republic. Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Prague, Czech Republic.

700    1_

$a Neděla, Vilém $u Institute of Scientific Instruments of the Academy of Sciences of the Czech Republic, Brno, Czech Republic.

700    1_

$a Tihlaříková, Eva $u Institute of Scientific Instruments of the Academy of Sciences of the Czech Republic, Brno, Czech Republic.

700    1_

$a Žárský, Viktor $u Department of Experimental Plant Biology, Faculty of Sciences, Charles University, Prague, Czech Republic. Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Prague, Czech Republic.

773    0_

$w MED00005317 $t Plant physiology $x 1532-2548 $g Roč. 176, č. 3 (2018), s. 2040-2051

856    41

$u https://pubmed.ncbi.nlm.nih.gov/29301954 $y Pubmed

910    __

$a ABA008 $b sig $c sign $y a $z 0

990    __

$a 20190405 $b ABA008

991    __

$a 20190405100552 $b ABA008

999    __

$a ok $b bmc $g 1392258 $s 1051253

BAS    __

$a 3

BAS    __

$a PreBMC

BMC    __

$a 2018 $b 176 $c 3 $d 2040-2051 $e 20180104 $i 1532-2548 $m Plant physiology $n Plant Physiol $x MED00005317

LZP    __

$a Pubmed-20190405