Entries by Philip Carella

Leaf age dictates abiotic versus biotic stress signalling in Arabidopsis (PNAS)

Plants sense and respond to various external stimuli throughout their lifespan. During stress responses brought forth by abiotic or biotic factors, molecular and physiological adjustments mediated by distinct yet interconnected hormone pathways play critical roles in plant survival. Berens et al. investigate how leaves of the Arabidopsis rosette prioritize stress signalling outputs during combined or […]

A smut fungus of Brassicaceae plants uses conserved and unique strategies to manipulate perennial hosts ($) New Phytol.

Biotrophic phytopathogens manipulate living hosts for the procurement of nutrients essential for growth and reproduction. It is therefore critical for invading biotrophs to evade or suppress immune responses without impacting overall plant function. In a recent study published in New Phytologist (2019), Courville et al. resolve the genomic and transcriptomic signatures of the smut fungus […]

A key role for flavanols in the promotion of pollen success (PNAS) ($)

The reproductive success of angiosperms relies on the fertilization of the female gametophyte (egg sac) by pollen that travels long-distances in the pistil. Previous studies suggest a role for phenylpropanoid-related metabolites (flavonoids and anthocyanins) in controlling pollen growth and fertilization, however a mechanistic understanding of their function during this critical developmental process remains unknown. In […]

Review: Nicotiana benthamiana: a workhorse of model plants (Annu Rev Phytopathol)

For years, scientists have relied on model species to investigate the fundamental nature of plants. Not surprisingly, these systems have facilitated our combined efforts for a deeper understanding of complex plant phenomena, from the coordinated orchestration of developmental programs to the emerging interconnected networks controlling responses to stressful stimuli. In an insightful review now published […]

Symplastic coordination of root nodule development (Curr. Biol.)

The establishment of root nodule symbiosis in legume roots involves the perception, infection, and accommodation of nitrogen-fixing rhizobia. The de novo formation of root nodules relies on complex developmental programs coordinated through different tissues via unknown cellular routes. Gaudioso-Pedraza et al. investigated the importance of plasmodesmatal cell-cell junctions (PD) for the initiation of root nodule […]

A conserved ABA signaling module regulates dormancy in liverworts (Curr Biol)

Plants can strategically maintain a state of dormancy to prevent germination and growth under unfavorable environmental conditions. In evolutionarily young lineages, dormancy is regulated by a canonical abscisic acid signalling pathway comprised of ABA receptors (PYR/PYL/RCAR), the negative regulator protein phosphatase 2C (PP2C) ABI1 (Abscisic acid Insensitive1), SNF1-related protein kinase2 (SnrK2), and ABA-associated transcriptional machinery […]

Glutamate is a wound-induced signal that activates long-distance calcium signaling (Science)

Several years of intensive research have revealed a suite of mobile signals that travel long-distances to inform meristems on developmental phase transitions or to protect distal plant tissues from abiotic or biotic stressors. In a new article published in Science, Toyota et al. (2018) identify a role for glutamate as a wound-induced signal that activates […]

A shoot-derived miRNA ensures susceptibility to beneficial rhizobacteria in legumes (Science)

Nitrogen-fixing rhizobacteria and leguminous plants engage in a tightly controlled root symbiosis resulting from bacteria-to-plant as well as (plant) shoot-to-root communication. This interplay controls the initiation and maintenance of root nodule development while preventing the over-production of nodules. In a keystone article published in Science, Tsikou et al. discovered that a shoot-derived microRNA is responsible […]

Arabidopsis seeds delay germination in the presence of pathogens (eLIFE)

The rhizosphere represents a complex and dynamic environment that poses many challenges for seed germination and seedling establishment. While a number of well-characterized abiotic factors and hormone signaling pathways are known to contribute to the initiation of seed germination, our current understanding of how plant pathogenic bacteria impact germination is poorly resolved. In a recent […]