Enhanced cuticle accumulation by employing MIXTA-like transcription factors

Abstract

The cuticle covers almost the entire aerial surface of terrestrial plants, and provides protection from abiotic and biotic stresses. Cuticles basically consist of wax and cutin, and are produced with variable structures and thicknesses depending on the plant and organ. The application of plant cuticles to improve stress tolerance and wax production requires the deposition of the cuticle at specific times to avoid undesirable side effects. We previously showed that the MYB106 and MYB16 MIXTA-like transcription factors regulate cuticle formation. However, MYB106 over-expression results in severe dwarfism. In this study, we identified genes downstream of these MYB transcription factors and used their promoters to express MYB106 and MYB16 fused to the strong transcriptional activation domain, VP16. Comparisons of plant growth and cuticle morphology revealed that MYB106 and MYB16 preferentially produced cuticles that are typically observed in petals and leaves, respectively. Additionally, the CYP77A6 and CYP86A4 promoters effectively induced cuticle accumulation in leaves and petals, respectively, without inhibiting plant growth. Our strategy may be useful for increasing or altering cuticles in agronomically important plants.

RNAi suppression of DNA methylation affects the drought stress response and genome integrity in transgenic poplar

“…Several transcription factors, such as SVP, MYB48, ERF1 , acting in phytohormone pathways and involved in biotic and abiotic stresses were also upregulated in RNAi‐ ddm1 lines in comparison to WT under water deficit (Sun & Yu, 2015; Bechtold et al ., 2016; He et al ., 2016; Wang et al ., 2017; Heyman et al ., 2018; Wang et al ., 2018; Guo et al ., 2019). Other DEGs, including genes involved in the leaf cuticle and waxes ( MYB106 , CER8 , FLA12 ), could also partly explain the improved tolerance to moderate water deficit in RNAi‐ ddm1 lines by preventing uncontrolled water loss (Chen et al ., 2011; Oshima & Mitsuda, 2013, 2016; Wettstein‐Knowles, 2016).…”

Two R2R3‐MYB genes cooperatively control trichome development and cuticular wax biosynthesis in Prunus persica

“…This indicates that trichome‐related MYB regulators might be different among plant species. Additionally, AtMYB16 and its closely related MYBs such as AmMYBML2 in Antirrhinum majus and PhMYB1 in Petunia hybrid have similar functions in regulating the development of conical epidermal cells in petals (Baumann et al ., 2007; Di Stilio et al ., 2009; Oshima & Mitsuda, 2016). Here, our results showed that PpMYB25 and PpMYB26 had high levels of expression in petal (Fig.…”

Misregulation of MYB16 causes stomatal cluster formation by disrupting polarity in asymmetric cell division

“…Of note, plants expressing MYB16 driven by the promoter of another downstream target, CYP86A4, do not show any stomatal phenotype. (Oshima and Mitsuda, 2016) Given that stomatal clusters are in CYP77A6p::MYB16-VP16 plants only, we wondered whether CYP77A6 or CYP86A4 has a distinct expression pattern in epidermis. We analyzed their transcriptional reporters by fusing promoters with nucleus-localized fluorescent protein (nucEGFP) and distinguished stomatal linage cells by staining cell outlines with propidium iodide (PI).…”

“…The form was created by fusion with the promoter from its downstream target, CYP77A6, and a transcription activation domain, VP16. Of note, plants expressing MYB16 driven by the promoter of another downstream target, CYP86A4, do not show any stomatal phenotype (Oshima and Mitsuda, 2016). Given that stomatal clusters are in CYP77A6p::MYB16-VP16 plants only, we wondered whether CYP77A6 or CYP86A4 has a distinct expression pattern in epidermis.…”