Convergent evolution of gene regulatory networks underlying plant adaptations to dry environments

Plants transitioned from an aquatic to a terrestrial lifestyle during their evolution. On land, fluctuations on water availability in the environment became one of the major problems they encountered. The appearance of morpho-physiological adaptations to cope with and tolerate water loss from the cells was undeniably useful to survive on dry land. Some of these adaptations, such as carbon concentrating mechanisms (CCMs), desiccation tolerance (DT) and root impermeabilization, appeared in multiple plant lineages. Despite being crucial for evolution on land, it has been unclear how these adaptations convergently evolved in the various plant lineages. Recent advances on whole genome and transcriptome sequencing are revealing that co-option of genes and gene regulatory networks (GRNs) is a common feature underlying the convergent evolution of these adaptations. In this review we address how the study of CCMs and DT have provided insight into convergent evolution of GRNs underlying plant adaptation to dry environments, and how these insights could be applied to currently emerging understanding of evolution of root impermeabilization through different barrier cell types. We discuss examples of co-option, conservation, and innovation of genes and GRNs at the cell, tissue and organ levels revealed by recent phylogenomic (comparative genomic) and comparative transcriptomic studies.

An Approach to Adaptive Sustainable Facades Inspired by Plants

Nowadays, and under the global warming circumstances we are facing, particularly those resulting from the building sectors, many directions for more sustainable and eco-friendly concepts have emerged. From these sustainability approaches is the “Biomimicry” approach. This approach represents the science of imitating and benefiting from nature’s principles. Nature has provided various strategies to adapt to the surrounding conditions. There are several methodologies and tools developed following the biomimicry approach and taking nature as inspiration. However, difficulties arise in collaborating more than one discipline, which consumes a lot of time and effort, consequently cost. Furthermore, the existing methodologies are still too generic for architects. Therefore, this paper aims at developing a platform that integrates different methodologies, approaches, and tools comprehensively.In this paper, the focus would be on plant adaptations. A more focus would be on the building’s envelope specifically due to its valuable contribution to the building’s overall energy consumption. The paper seeks to integrate the plant’s adaptive strategies to the building envelope. The motivation is to tackle solutions for the building envelope environmental problems mainly for heat, water air, and light challenges.

Applied and complicated tasks on plant morphology with elements of ecology, physiology and evolution

rative complicated tasks on plant morphology which require the knowledge on ecology, plant physiology and evolutionary theory. The main purpose of such tasks is demonstration on concrete examples the relationship between structure and function, illustration of plant adaptations to the specific environment, developing of students’ critical mentality, ability to propose and prove work hypothesis. Some tasks are depended upon the practice work with regional natural plant objects – for the revealing of their taxonomic status, morphological peculiarities and adaptations. In many tasks the plants with parts and organs which may be mistook for other organs are figured (for example submarine leaves or transformed sprouts may be mistook upon the roots, stalks – upon leaves, algae – upon higher plants). The part of tasks is devoted to functional diversity and evolutional development of vegetative organs. The performance of such tasks requires the deep knowledge on plant morphology and developed natural scientific mentality.

Exogenous hormones influence Brassica napus leaf cuticular wax deposition and cuticle function

Background Cuticular waxes cover plant surface and play important roles in protecting plants from abiotic and biotic stresses. The variations of wax deposition and chemical compositions under changing environments have been shown to be related to plant adaptations. However, it is still not clear whether the wax depositions could be adjusted to increase plant adaptations to stressed conditions. Methods In this study, exogenous methyl jasmonate (MeJA), the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) and salicylic acid (SA) were applied to test their effects on cuticular wax deposition in two Brassica napus cultivars, Zhongshuang 9 (ZS9, low wax coverage ) and Yuyou 19 (YY19, high wax coverage). Next, we measured the water loss rate and the transcriptional expression of genes involved in wax biosynthesis as well as genes related to disease defense. Results Seven wax compound classes, including fatty acids, aldehydes, alkanes, secondary alcohols, ketones, and unbranched as well as branched primary alcohols, were identified in B. napus leaf wax mixtures. MeJA, SA and ACC treatments had no significant effect on total wax amounts in YY19, whereas ACC reduced total wax amounts in ZS9. Overall, hormone treatments led to an increase in the amounts of aldehydes and ketones, and a decrease of secondary alcohol in ZS9, whereas they led to a decrease of alkane amounts and an increase of secondary alcohol amounts in YY19. Concomitantly, both cultivars also exhibited different changes in cuticle permeability, with leaf water loss rate per 15 min increased from 1.57% (averaged across treatments) at 1.57% (averaged across treatments) at 15 min to 3.12% at 30 min for ZS9 (except for ACC treated plant) and decreased for YY19. MeJA-treated plants of both cultivars relatively had higher water loss rate per 15 min when compared to other treatments. Conclusion. Our findings that B. napus leaf wax composition and cuticle permeability are altered by exogenous SA, MeJA and ACC suggest that the hormone treatments affect wax composition, and that the changes in wax profiles would cause changes in cuticle permeability.

Molecular Mechanisms of Brassinosteroid-Mediated Responses to Changing Environments in Arabidopsis

Plant adaptations to changing environments rely on integrating external stimuli into internal responses. Brassinosteroids (BRs), a group of growth-promoting phytohormones, have been reported to act as signal molecules mediating these processes. BRs are perceived by cell surface receptor complex including receptor BRI1 and coreceptor BAK1, which subsequently triggers a signaling cascade that leads to inhibition of BIN2 and activation of BES1/BZR1 transcription factors. BES1/BZR1 can directly regulate the expression of thousands of downstream responsive genes. Recent studies in the model plant Arabidopsis demonstrated that BR biosynthesis and signal transduction, especially the regulatory components BIN2 and BES1/BZR1, are finely tuned by various environmental cues. Here, we summarize these research updates and give a comprehensive review of how BR biosynthesis and signaling are modulated by changing environments and how these changes regulate plant adaptive growth or stress tolerance.