Biology subjects

Castorina, G.

Publications and source records attributed to Castorina, G..

3 recordsLinked to original sources

bioRxiv2024

Genetic interaction between GL15 and FDL1 modulates juvenile cuticle deposition and leaf permeability in maize

The plant cuticle is a hydrophobic layer that serves as the primary barrier between plant surfaces and the external environment, limiting water loss and protecting against various stresses. This study investigates the genetic interaction between the maize ZmFDL1 and ZmGL15 genes and their role in modulating juvenile cuticle deposition and leaf permeability. The research was undertaken to understand how these genes influence cuticle composition and structure, which are crucial for plant protection against environmental stresses such as drought. We analysed the chemical composition of cutin and waxes, as well as cuticle-dependent leaf permeability. Our findings reveal that ZmFDL1 and ZmGL15 individually and synergically regulate the deposition of cuticular components, with significant impacts on leaf permeability. The gl15-S mutant exhibited an adult-like cuticle with higher cutin and lower wax contents, leading to reduced leaf permeability and improved water retention under drought conditions. These results highlight the importance of cutin in forming an effective water barrier and suggest that modulating cuticle composition with enhanced cutin content could be a strategy for improving drought tolerance in crops. This study provides new insights into the genetic regulation of cuticle biosynthesis and its relevance for plant adaptation to water scarcity. HighlightO_LIZmFDL1 and ZmGL15 interact to modulate cuticle composition and reduce leaf water loss. C_LIO_LIZmFDL1 and ZmGL15 genes regulate juvenile cuticle deposition in maize. C_LIO_LIThe gl15-S mutant shows an adult-like cuticle with higher cutin and lower wax contents. C_LIO_LIThe gl15-S mutation is epistatic to fdl1-1, partially rescuing the defective fdl1 cuticle phenotype. C_LIO_LIThe cuticle composition in gl15-S mutants leads to reduced leaf permeability and improved water retention under drought conditions. C_LIO_LICuticular layer with enhanced cutin content could improve drought tolerance in crops. C_LI

genetics↗

bioRxiv2024

Abscisic acid and GIGANTEA signalling converge to regulate the recruitment of CONSTANS to the FT promoter and activate floral transition

Plants align flowering with optimal seasonal conditions to increase reproductive success. This process depends on modulating signalling pathways that respond to diverse environmental and hormonal inputs, thereby regulating the transition to flowering at the shoot apical meristem. In Arabidopsis, long-day photoperiods (LDs) stimulate the transcription of FLOWERING LOCUS T (FT), encoding the main florigenic signal. FT activation is mediated by the transcriptional regulator CONSTANS (CO), which binds to the CO responsive elements (COREs) located in the proximal FT promoter region. The phytohormone abscisic acid also (ABA) contributes to FT activation together with GIGANTEA (GI) to regulate drought escape (DE). Whether CO is a target of ABA and GI actions for the regulation of FT is, however, unknown. Here, we report that ABA and its signalling components promote CO recruitment to the CORE1/2, without causing reductions in the diel pattern of CO protein accumulation. ChIPseq analyses show that ABA broadly shapes the CO DNA binding landscape, which is enriched at the promoters of genes involved in the response to abiotic stress. We also found that GI promotes CO recruitment to the CORE1/2 region, and that CO recruitment is required for the accumulation of RNAPol II at the transcription start site of FT. Finally, we show that GI and ABA signalling pathways are largely epistatic in the control of flowering time, suggesting their involvement in the same molecular process. Taken together, these observations suggest that varying water deficit conditions modulate CO recruitment and FT expression, thus dictating DE strategies in Arabidopsis. HighlightABA and GIGANTEA signalling promote FLOWERING LOCUS T (FT) transcriptional activation by regulating the binding of the transcription factor CONSTANS to the proximal FT promoter.

plant biology↗

bioRxiv2020

The drought-responsive ZmFDL1 gene regulates cuticle biosynthesis and cuticle-dependent leaf permeability

In higher plants, the outer surface of the 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 cuticle deposition, during the juvenile phase of in maize (Zea mays) plant development, and cuticle-dependent leaf permeability are controlled by the MYB transcription factor ZmMYB94/FUSED LEAVES1 (ZmFDL1). Biochemical analysis showed that in fdl1-1 mutant seedlings at the coleoptile stage both cutin and wax biosynthesis and deposition were altered. Among cutin compounds, {omega}-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 novel candidate genes involved in lipid metabolism and the assembly of a proposed pathway for cuticle biosynthesis in maize. Lack of ZmFDL1 affects the expression of genes located in different modules of the pathway and correspondence between gene transcriptional variations and biochemical defects have been highlighted. A decrease in cuticle-dependent leaf permeability was observed in maize seedlings exposed to drought as well as ABA treatment, which implies coordinated changes in the transcript levels of ZmFDL1 and associated genes. Overall, our results suggest that the response to water stress implies the activation of wax biosynthesis and the involvement of by both ZmFDL1 and ABA regulatory pathways. One-Sentence SummaryCuticle biosynthesis and cuticle-mediated drought-response during the juvenile phase of maize plant growth, are regulated by the MYB transcription factor fused leaves1 (ZmFDL1) and influenced by ABA.

plant biology↗