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Robertson, I.

Publications and source records attributed to Robertson, I..

4 recordsLinked to original sources

Characterization of pre-analytical blood collection and stabilization parameters to maintain endogenous protein levels for remote blood sampling technology

Blood biomarkers are central to monitoring disease progression and evaluating treatment responses, yet traditional venipuncture captures a single physiological snapshot in time and becomes burdensome with repeated sampling. Remote blood self-sampling offers a path toward longitudinal, decentralized monitoring, but maintaining protein integrity from draw to analysis remains a critical challenge. Here, we optimized pre-analytical blood collection and stabilization parameters to maintain protein levels at the time of collection for use with remote sampling technology. First, we optimized blood collection time with Tasso remote self-sampling devices to minimize interference from clotting, finding that a 2.5 min collection time best reduces clot formation while collecting enough blood. Next, we found that Protein Plus, a commercial protein stabilizer, limited hemolysis (a metric for stabilizer efficacy) in venous blood for up to 5 days at 25{degrees}C-35{degrees}C and for 1 day at 40{degrees}C. In addition, we optimized the stabilizer volume and acceptable blood volume range for self-sampling as the stabilizer efficacy is impacted by the stabilizer to blood ratio and collection volume can vary with remote self-sampling devices. Finally, we incubated stabilized blood samples collected via Tasso device at 25{degrees}C-35{degrees}C for 72 h, mimicking a 2-day shipping period. Using a panel of 21 inflammatory proteins, we found that Protein Plus limited intracellular protein release for various proteins (e.g., VEGF-A, CCL11, and IL-8), inhibited protein degradation for CCL2, and enabled minimal hemolysis. These results support Protein Plus as a viable stabilization strategy for remote blood collection technology targeting longitudinal inflammatory protein monitoring.

biochemistry↗

Two cowpea Rubisco activase isoforms for crop thermotolerance

O_LIA vital crop for sub-Saharan Africa, cowpea productivity is threatened by climate change, including increased heatwave intensity, duration, and frequency. Rubisco activase (Rca) is a key molecular chaperone that maintains Rubisco activity and due to its thermal sensitivity is a key target for improving crop climate resilience. C_LIO_LIWe identified and characterised four Rca isoforms in Vigna unguiculata (L.) Walp. cv. IT97K-499-35 in vitro: Rca1{beta}, Rca8, Rca10 and Rca10{beta}. Cowpea leaf and plant growth traits were also investigated during a 5-day +10 {degrees}C heatwave that included assessment of Rubisco and Rca activity in leaf extracts, and relative changes in the abundance of the four Rca isoforms. C_LIO_LICowpea Rca10 and Rca10{beta} had higher thermal maxima, broader thermal optima and higher rates of ATP hydrolysis and Rubisco reactivation in vitro. In the absence of water deficit, the heatwave caused only mild effects, including increases in leaf temperature and expression of Rca10, small decreases in Rubisco activity and activation state, and unaltered temperature response of Rubisco activation by Rca. C_LIO_LIThe superior Rca10 and Rca10{beta} isoforms offer the prospect of enhancing the thermotolerance of cowpea and other crops in anticipation of more extreme future heatwaves. C_LI

plant biology↗

Chickpea (Cicer arietinum L.) root system architecture adaptation to initial soil moisture improves seed development in dry-down conditions

Soil water deficit (WD) impacts vascular plant phenology, morpho-physiology, and reproduction. Chickpea, which is mainly grown in semi-arid areas, is a good model plant to dissect mechanisms involved in drought resistance. We used a rhizobox-based phenotyping system to simultaneously and non-destructively characterise root system architecture (RSA) dynamics and water use (WU) patterns. We compared the drought-adaptive strategies of Teketay to the drought-sensitive genotype ICC 1882 in high and low initial soil moisture without subsequent irrigation. WD restricted vegetative and reproductive organ biomass for both genotypes. Teketay displayed greater adaptability for RSA dynamics and WU patterns and revealed different drought adaptive strategies depending on initial soil moisture: escape when high, postponement when low. These strategies were manifested in distinct RSA dynamics: in low initial soil moisture, its reduced root growth at the end of the vegetative phase was followed by increased root growth in deeper, wetter soil strata, which facilitated timely WU for seed development and produced better-developed seeds. We demonstrate that RSA adaptation to initial soil moisture is one mechanism by which plants can tolerate WD conditions and ensure reproduction by producing well-developed seeds. Our approach will help in identifying the genetic basis for large plasticity of RSA dynamics which enhances the resilience with which crops can optimally adapt to various drought scenarios. HighlightRoot system architecture and water use patterns change dynamically for distinct drought adaptation strategies in chickpea.

plant biology↗

Affordable and robust phenotyping framework to analyse root system architecture of soil-grown plants

The analysis of root system growth, root phenotyping, is important to inform efforts to enhance plant resource acquisition from soils. However, root phenotyping remains challenging due to soil opacity and requires systems that optimize root visibility and image acquisition. Previously reported systems require costly and bespoke materials not available in most countries, where breeders need tools to select varieties best adapted to local soils and field conditions. Here, we present an affordable soil-based growth container (rhizobox) and imaging system to phenotype root development in greenhouses or shelters. All components of the system are made from commodity components, locally available worldwide to facilitate the adoption of this affordable technology in low-income countries. The rhizobox is large enough (~6000 cm2 visible soil) to not restrict vertical root system growth for at least seven weeks after sowing, yet light enough (~21 kg) to be routinely moved manually. Support structures and an imaging station, with five cameras covering the whole soil surface, complement the rhizoboxes. Images are acquired via the Phenotiki sensor interface, collected, stitched and analysed. Root system architecture (RSA) parameters are quantified without intervention. RSA of a dicot (chickpea, Cicer arietinum L.) and a monocot (barley, Hordeum vulgare L.) species, which exhibit contrasting root systems, were analysed. The affordable system is relevant for efforts in Ethiopia and elsewhere to enhance yields and climate resilience of chickpea and other crops for improved food security.\n\nSignificance StatementAn affordable system to characterize root system architecture of soil-grown plants was developed. Using commodity components, this will enable local efforts world-wide to breed for enhanced root systems.

plant biology↗