Worrall, D. | Search bioRxiv

bioRxiv2025

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↗

bioRxiv2023

Assessing the performance of commercial reagent antibodies

Antibodies are critical reagents to detect and characterize proteins. It is commonly understood that many commercial antibodies do not recognize their intended targets, but information on the scope of the problem remains largely anecdotal, and as such, feasibility of the goal of at least one potent and specific antibody targeting each protein in a proteome cannot be assessed. Focusing on antibodies for human proteins, we have scaled a standardized characterization approach using parental and knockout cell lines (Laflamme et al., 2019) to assess the performance of 614 commercial antibodies for 65 neuroscience-related proteins. Side-by-side comparisons of all antibodies against each target, obtained from multiple commercial partners, demonstrates that: i) more than 50% of all antibodies failed in one or more tests, ii) yet, [~]50-75% of the protein set was covered by at least one high-performing antibody, depending on application, suggesting that coverage of human proteins by commercial antibodies is significant; and iii) recombinant antibodies performed better than monoclonal or polyclonal antibodies. The hundreds of underperforming antibodies identified in this study were found to have been used in a large number of published articles, which should raise alarm. Encouragingly, more than half of the underperforming commercial antibodies were reassessed by the manufacturers, and many had alterations to their recommended usage or were removed from the market. This first such study helps demonstrate the scale of the antibody specificity problem but also suggests an efficient strategy toward achieving coverage of the human proteome; mine the existing commercial antibody repertoire, and use the data to focus new renewable antibody generation efforts.

molecular biology↗