Plant science’s next top models

Abstract

Background Model organisms are at the core of life science research. Notable examples include the mouse as a model for humans, baker’s yeast for eukaryotic unicellular life and simple genetics, or the enterobacteria phage λ in virology. Plant research was an exception to this rule, with researchers relying on a variety of non-model plants until the eventual adoption of Arabidopsis thaliana as primary plant model in the 1980s. This proved to be an unprecedented success, and several secondary plant models have since been established. Currently, we are experiencing another wave of expansion in the set of plant models. Scope Since the 2000s, new model plants have been established to study numerous aspects of plant biology, such as the evolution of land plants, grasses, invasive and parasitic plant life, adaptation to environmental challenges, and the development of morphological diversity. Concurrent with the establishment of new plant models, the advent of the ‘omics’ era in biology has led to a resurgence of the more complex non-model plants. With this review, we introduce some of the new and fascinating plant models, outline why they are interesting subjects to study, the questions they will help to answer, and the molecular tools that have been established and are available to researchers. Conclusions Understanding the molecular mechanisms underlying all aspects of plant biology can only be achieved with the adoption of a comprehensive set of models, each of which allows the assessment of at least one aspect of plant life. The model plants described here represent a step forward towards our goal to explore and comprehend the diversity of plant form and function. Still, several questions remain unanswered, but the constant development of novel technologies in molecular biology and bioinformatics is already paving the way for the next generation of plant models.

Guanosine tetraphosphate (ppGpp) accumulation inhibits chloroplast gene expression and promotes super grana formation in the mossPhyscomitrium(Physcomitrella)patens

“…It would also be interesting to investigate gametophore growth in P. patens mutants affected in photosystem composition to understand whether our observation is specific to ppGpp accumulation or reflects a more general ability of mosses to grow despite defects in photosynthesis (Pinnola et al ., 2015; Pinnola et al ., 2018; Peng et al ., 2019; Storti et al ., 2020). Analysis in other model bryophytes, such as the liverwort Marchantia polymorpha , would also help to determine whether this characteristic can be generalized to all non-vascular plants (Cesarino et al ., 2020).…”

Novel genome characteristics contribute to the invasiveness of Phragmites australis (common reed)

“…The Great Lakes Restoration Initiative has identified invasive species (including P. australis) as one of its five most urgent issues since 2010 (Great Lake Restoration Initiative, 2019). Invasive P. australis has also been recognized as the leading plant model for studying genetic mechanisms underlying plant invasions (Cesarino et al, 2020;Meyerson et al, 2016). P. australis therefore provides an excellent system to test genetic adaptations and control measures in plant invasions, given that both native and invasive populations coexist over a large geographic range (Figure 1a, b).…”

Cross-stress gene expression atlas of Marchantia polymorpha reveals the hierarchy and regulatory principles of abiotic stress responses

“…The Marchantia genome contains all necessary components for most land-plant signalling pathways, but compared to flowering plants, the components are reduced to the minimum number, making it easier to dissect the pathways 8 . For example, the auxin signalling network in Marchantia is simple yet functional, with all relevant genes existing as single orthologs 10 . Similarly, cellulose biosynthesis in Marchantia uses the same but simplified machinery; while Arabidopsis thaliana contains ten cellulose synthases that exist in multimeric complexes, Marchantia has only two 11 .…”