Barley HvBODYGUARD1 controls cuticular specialisations regulated by SHINE transcription factors

TY - JOUR

T1 - Barley HvBODYGUARD1 controls cuticular specialisations regulated by SHINE transcription factors

AU - Mcallister, Trisha

AU - Campoli, Chiara

AU - Liu, Linsan

AU - Chia, Tansy

AU - Fisher, Ronan

AU - Horsnell, Richard

AU - Prescott, Alan

AU - Shoesmith, Jennifer

AU - Eskan, Mhmoud

AU - Iredale, Alasdair

AU - Nuter, Mirjam

AU - Ramsay, Luke

AU - Bayer, Micha M

AU - Milne, Linda

AU - Schreiber, Miriam

AU - Rajarathinam, Yogeswari

AU - Wahl, Vanessa

AU - Waugh, Robbie

AU - Cockram, James

AU - McKim, Sarah M.

N1 - Publisher Copyright: © 2026 The Author(s). New Phytologist © 2026 New Phytologist Foundation.

PY - 2026/5/27

Y1 - 2026/5/27

N2 - Land plants secrete a protective outer cuticular layer with diverse functions. Barley (Hordeum vulgare L.) develops two cuticular specialisations: the β-diketone rich wax bloom on vegetative tissues and an adherent grain surface which sticks to the hulls, leading to barley's distinctive ‘covered’ grain phenotype. Two barley SHINE transcription factors, HvWIN1 and NUD, promote the wax bloom and covered grain phenotypes, respectively, yet we know little about other genes involved. We investigated a barley mutant showing defects in both cuticular specialisations to better understand the networks and processes underlying these traits. We identified the barley BODYGUARD1 (HvBDG1) gene encoding an α/β hydrolase as crucial for leaf cuticular integrity and wax-bloom deposition. Mining tetraploid wheat (Triticum turgidum ssp. durum) mutant populations demonstrated that BDG1 and WIN1 orthologues also control the wax bloom in wheat. We further reveal that NUD and HvWIN1 retain functional, independent overlap in leaf cuticle integrity and hull adhesion in barley, functions which involve upregulation of HvBDG1 and other direct or indirect targets, shared and distinct, depending on the stage and tissue. Our work greatly expands our knowledge of genetic and developmental mechanisms underlying shared and distinctive cuticular features in plants.

AB - Land plants secrete a protective outer cuticular layer with diverse functions. Barley (Hordeum vulgare L.) develops two cuticular specialisations: the β-diketone rich wax bloom on vegetative tissues and an adherent grain surface which sticks to the hulls, leading to barley's distinctive ‘covered’ grain phenotype. Two barley SHINE transcription factors, HvWIN1 and NUD, promote the wax bloom and covered grain phenotypes, respectively, yet we know little about other genes involved. We investigated a barley mutant showing defects in both cuticular specialisations to better understand the networks and processes underlying these traits. We identified the barley BODYGUARD1 (HvBDG1) gene encoding an α/β hydrolase as crucial for leaf cuticular integrity and wax-bloom deposition. Mining tetraploid wheat (Triticum turgidum ssp. durum) mutant populations demonstrated that BDG1 and WIN1 orthologues also control the wax bloom in wheat. We further reveal that NUD and HvWIN1 retain functional, independent overlap in leaf cuticle integrity and hull adhesion in barley, functions which involve upregulation of HvBDG1 and other direct or indirect targets, shared and distinct, depending on the stage and tissue. Our work greatly expands our knowledge of genetic and developmental mechanisms underlying shared and distinctive cuticular features in plants.

KW - BODYGUARD

KW - cereal

KW - cuticle

KW - grain

KW - SHINE transcription factors

KW - wax bloom

KW - barley

KW - wheat

U2 - 10.1111/nph.71287

DO - 10.1111/nph.71287

M3 - Article

SN - 0028-646X

JO - New Phytologist

JF - New Phytologist

ER -