Entries by Mary Williams

Shape-Shifters: How Strigolactone Signaling Helps Shape the Shoot

IN BRIEF by Jennifer Lockhart jlockhart@aspb.org When a deer eats the primary shoot of a plant, this can activate a nearby dormant axillary bud, causing it to form a secondary shoot. Genetic and environmental factors also affect shoot architecture, which strongly influences crop productivity. Changes in shoot architecture are mediated by long-distance signals, including phytohormones. […]

Ticket to Ride: tRNA-Related Sequences and Systemic Movement of mRNAs

IN BRIEF by Jennifer Mach jmach@aspb.org Movement of macromolecules through the plant phloem provides a mechanism for long-distance signaling that plants use in development, disease resistance, and other adaptive responses (reviewed in Spiegelman et al., 2013). For example, full-length RNAs, such as the Arabidopsis thaliana GIBBERELLIC ACID INSENSITIVE and potato (Solanum tuberosum) BEL5 mRNAs, and […]

Thinking Outside the Plant: Exploring Phloem Development Using VISUAL

IN BRIEF by Jennifer Lockhart  jlockhart@aspb.org Investigating how plants grow and develop often requires a bit of creativity. For example, deep within the plant, the vascular cambium, a layer of embryonic, highly cytoplasmic cells, gives rise to xylem and phloem tissue, which must expand throughout the plant’s lifetime. Water and nutrients primarily flow through the […]

Review: Plant synthetic biology for molecular engineering of signalling and development

Nemhauser and Torii define synthetic biology as “an engineering approach to design, build and analyize dynamic molecular devices and/or pathways from biological components to produce cells and organisms with customized functionality.” In their review, they describe several plant synthetic biology approaches and outcomes, including efforts to identify and remediate toxins, engineer receptors, modify signals and […]

Review: Plant synthetic promoters and transcription factors

Many plant traits are multigenic, so engineering them requires modulating the expression of several genes simultaneously. Synthetic promoters and transcription factors offer such a possibility. For example, a cis-element can be introduced into the promoter of each gene of interest, and a synthetic transcription factor that activates gene expression via this cis-element and is itself […]

Review: Multi-gene engineering in plants with RNA-guided Cas9 nuclease ($)

Raitskin and Patron review efforts to express multiple single guide RNA (sgRNAs) and Cas9 in plants for the coordinated expression of many genes. They argue for the need to create single plasmids carrying the sgRNAs and Cas9, using a Type IIS restriction endonuclease-mediated assembly method. Curr. Opin. Biotech. 10.1016/j.copbio.2015.11.008

Review: Using CRISPR/Cas in three dimensions: towards synthetic plant genomes, transcriptomes and epigenomes

Puchta reviews the different ways that CRISPR/Cas9 can be used in synthetic biolgy, beyond the common gene-editing function. For example, the Cas9 protein can be fused to other proteins that activate or repress transcription, and targeted to different promoters using guide RNAs. He further explores the possibility of one day producing synthetic plant genomes. Plant […]

Quantitative characterization of genetic parts and circuits for plant synthetic biology

Control of gene expression involves both activation and repression of transcription. Schaumberg et al. used transient expression in Arabidopsis and sorghum protoplasts and dual-luciferase outputs to rapidly quantitate synthetic repressors and repressible promoters, and verified their results in transgenic Arabidopsis plants. Nature Methods 10.1038/nmeth.3659