Biology subjects

Youles, M.

Publications and source records attributed to Youles, M..

4 recordsLinked to original sources

bioRxiv2026

AMBER and GOLD: Polycistronic Genes for Betaxanthin Production in Plants

Genetically encoded pigments are powerful visual reporters and creative tools for biology, yet in plants the palette of pigment biosynthesis genes has remained largely limited to red betacyanins encoded by RUBY. Here we develop and characterize three new polycistronic constructs AMBER_v1, AMBER_v2, and GOLD that contain betalain biosynthesis enzymes to produce yellow, fluorescent betaxanthins in plant tissues. These tools expand the palette of publicly available pigmentation genes for use in plant research, education, and floral design.

bioengineering↗

bioRxiv2023

pOPARA: Vectors for Golden Gate assembly of expression constructs containing the araBAD promoter

Heterologous protein production is often required to investigate the structural, biochemical, and biophysical properties of a protein of interest. Frequently, optimisation of expression conditions is required to obtain soluble protein and maximise yield. Trialling a variety of solubility and purification tags, as well as constructs containing different regulatory elements, is desirable. Golden Gate cloning allows modular assembly of different constructs using Type IIS restriction enzymes. The pOPIN vector suite, which utilises the T7 expression system, has been adapted to be compatible with Golden Gate assembly. Here, we present the pOPARA vectors. Expression from pOPARA vectors is driven by the araBAD promoter (pBAD) and is induced by addition of arabinose to the culture medium. pOPARA allows modular assembly of expression constructs using Golden Gate cloning with the CDS of interest and an optional C-terminal tag. pOPARA1 contains a carbenicillin resistance cassette flanked by restriction sites to allow exchange of the selectable markers. In pOPARA2, the carbenicillin resistance cassette has been exchanged for a spectinomycin resistance cassette. We demonstrate that both vectors can be used to express and produce a control protein.

molecular biology↗

bioRxiv2021

pOPIN-GG: A resource for modular assembly in protein expression vectors

The ability to recombinantly produce target proteins is essential to many biochemical, structural, and biophysical assays that allow for interrogation of molecular mechanisms behind protein function. Purification and solubility tags are routinely used to maximise the yield and ease of protein expression and purification from E. coli. A major hurdle in high-throughput protein expression trials is the cloning required to produce multiple constructs with different solubility tags. Here we report a modification of the well-established pOPIN expression vector suite to be compatible with modular cloning via Type IIS restriction enzymes. This allows users to rapidly generate multiple constructs with any desired tag, introducing modularity in the system and delivering compatibility with other modular cloning vector systems, for example streamlining the process of moving between expression hosts. We demonstrate these constructs maintain the expression capability of the original pOPIN vector suite and can also be used to efficiently express and purify protein complexes, making these vectors an excellent resource for high-throughput protein expression trials. HighlightsO_LIpOPIN-GG expression vectors allow for modular cloning enabling rapid screening of purification and solubility tags at no loss of expression compared to previous vectors. C_LIO_LICloning into the pOPIN-GG vectors can be performed from PCR products or from level 0 vectors containing the required parts. C_LIO_LISeveral vectors with different resistances and origins of replication have been generated allowing the effective co-expression and purification of protein complexes. C_LIO_LIAll pOPIN-GG vectors generated here are available on Addgene, as well as level 0 acceptors and tags. C_LI

biochemistry↗

bioRxiv2019

Estradiol-inducible AvrRps4 expression reveals distinct properties of TIR-NLR-mediated effector-triggered immunity

Plant nucleotide-binding domain, leucine-rich repeat receptor (NLR) proteins play important roles in recognition of pathogen-derived effectors. However, the mechanism by which plant NLRs activate immunity is still largely unknown. The paired Arabidopsis NLRs RRS1-R and RPS4, that confer recognition of bacterial effectors AvrRps4 and PopP2, are well studied, but how the RRS1/RPS4 complex activates early immediate downstream responses upon effector detection is still poorly understood. To study RRS1/RPS4 responses without the influence of cell-surface receptor immune pathways, we generated an Arabidopsis line with inducible expression of effector AvrRps4. Induction does not lead to hypersensitive cell death response (HR) but can induce electrolyte leakage, which often correlates with plant cell death. Activation of RRS1 and RPS4 without pathogens cannot activate mitogen-associated protein kinase cascades, but still activates upregulation of defense genes, and therefore resistance against bacteria.\n\nHighlightInducible expression of AvrRps4 activates RRS1/RPS4-mediated effector-triggered immunity without the presence of pathogens, allowing us to characterise downstream immune responses triggered by TIR-NLRs without cell-surface receptor-mediated immunity.

plant biology↗