Barley isochorismate synthase mutant is phylloquinone-deficient, but has normal basal salicylic acid level

TY - JOUR

T1 - Barley isochorismate synthase mutant is phylloquinone-deficient, but has normal basal salicylic acid level

AU - Qin, Yuan

AU - Torp, Anna Maria

AU - Glauser, Gaëtan

AU - Pedersen, Carsten

AU - Rasmussen, Søren K.

AU - Thordal-Christensen, Hans

PY - 2019/11/2

Y1 - 2019/11/2

N2 - Salicylic acid (SA) is an important signaling hormone in plant immunity. It can be synthesized by either the phenylpropanoid pathway or the isochorismate pathway, but mutant studies of this have been scarce in other species than Arabidopsis. Here we identified a mutation that introduced a stop-codon early in the barley gene for isochorismate synthase (ICS). We found that homozygous ics plants wilted if not sprayed with 1,4-dihydroxy-2-naphthoic acid, a precursor of phylloquinone, also synthesized via the isochorismate pathway. Interestingly, ics had unchanged SA, suggesting that the basal level of SA is synthesized via the phenylpropanoid pathway. Previous studies have failed seeing increased SA levels in barley after attack by the powdery mildew fungus, Blumeria graminis f.sp. hordei (Bgh), and indeed, we saw no changes in the interaction of ics with this fungus. Overall, we hope this mutant will be useful for other studies of SA in barley.

AB - Salicylic acid (SA) is an important signaling hormone in plant immunity. It can be synthesized by either the phenylpropanoid pathway or the isochorismate pathway, but mutant studies of this have been scarce in other species than Arabidopsis. Here we identified a mutation that introduced a stop-codon early in the barley gene for isochorismate synthase (ICS). We found that homozygous ics plants wilted if not sprayed with 1,4-dihydroxy-2-naphthoic acid, a precursor of phylloquinone, also synthesized via the isochorismate pathway. Interestingly, ics had unchanged SA, suggesting that the basal level of SA is synthesized via the phenylpropanoid pathway. Previous studies have failed seeing increased SA levels in barley after attack by the powdery mildew fungus, Blumeria graminis f.sp. hordei (Bgh), and indeed, we saw no changes in the interaction of ics with this fungus. Overall, we hope this mutant will be useful for other studies of SA in barley.

KW - barley

KW - isochorismate synthase

KW - phylloquinone

KW - Salicylic acid

UR - http://www.scopus.com/inward/record.url?scp=85073307380&partnerID=8YFLogxK

U2 - 10.1080/15592324.2019.1671122

DO - 10.1080/15592324.2019.1671122

M3 - Journal article

C2 - 31559895

AN - SCOPUS:85073307380

SN - 1559-2316

VL - 14

JO - Plant Signalling & Behavior

JF - Plant Signalling & Behavior

IS - 11

M1 - 1671122

ER -