In all land plants, the outer surface of aerial parts is covered by the cuticle, a complex lipid layer that constitutes a barrier against damages caused by environmental factors and provides protection against non-stomatal water loss. We show in this study that both cuticle deposition and cuticle-dependent leaf permeability during the juvenile phase of plant development are controlled by the maize (Zea mays) transcription factor ZmFUSED LEAVES 1 (FDL1)/MYB94. Biochemical analysis showed altered cutin and wax biosynthesis and deposition in fdl1-1 mutant seedlings at the coleoptile stage. Among cutin compounds, ω-hydroxy fatty acids and polyhydroxy-fatty acids were specifically affected, while the reduction of epicuticular waxes was mainly observed in primary long chain alcohols, and to a minor extent, long-chain wax esters. Transcriptome analysis allowed the identification of candidate genes involved in lipid metabolism and the assembly of a proposed pathway for cuticle biosynthesis in maize. Lack of ZmFDL1/MYB94 affects the expression of genes located in different modules of the pathway, and we highlighted the correspondence between gene transcriptional variations and biochemical defects. We observed decrease in cuticle-dependent leaf permeability in maize seedlings exposed to drought as well as to abscisic acid treatment, which implies coordinated changes in the transcript levels of ZmFDL1/MYB94 and associated genes. Overall, our results suggest that the response to water stress implies the activation of wax biosynthesis and the involvement of both ZmFDL1/MYB94 and abscisic acid regulatory pathways.
Drought-responsive ZmFDL1/MYB94 regulates cuticle biosynthesis and cuticle-dependent leaf permeability / G. Castorina, F. Domergue, M. Chiara, M. Zilio, M. Persico, V. Ricciardi, D.S. Horner, G. Consonni. - In: PLANT PHYSIOLOGY. - ISSN 0032-0889. - 184:1(2020 Sep 01), pp. 266-282.
|Titolo:||Drought-responsive ZmFDL1/MYB94 regulates cuticle biosynthesis and cuticle-dependent leaf permeability|
CASTORINA, GIULIA (Primo)
HORNER, DAVID STEPHEN (Penultimo)
CONSONNI, GABRIELLA (Ultimo) (Corresponding)
|Settore Scientifico Disciplinare:||Settore AGR/07 - Genetica Agraria|
Settore BIO/11 - Biologia Molecolare
Settore BIO/18 - Genetica
|Data di pubblicazione:||1-set-2020|
|Data ahead of print / Data di stampa:||14-lug-2020|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1104/pp.20.00322|
|Appare nelle tipologie:||01 - Articolo su periodico|