Multiplexed RNA profiling by regenerative catalysis enables blood-based subtyping of brain tumors.

Current technologies to subtype glioblastoma (GBM), the most lethal brain tumor, require highly invasive brain biopsies. Here, we develop a dedicated analytical platform to achieve direct and multiplexed profiling of circulating RNAs in extracellular vesicles for blood-based GBM characterization. The technology, termed 'enzyme ZIF-8 complexes for regenerative and catalytic digital detection of RNA' (EZ-READ), leverages an RNA-responsive transducer to regeneratively convert and catalytically enhance signals from rare RNA targets. Each transducer comprises hybrid complexes - protein enzymes encapsulated within metal organic frameworks - to configure strong catalytic activity and robust protection. Upon target RNA hybridization, the transducer activates directly to liberate catalytic complexes, in a target-recyclable manner; when partitioned within a microfluidic device, these complexes can individually catalyze strong chemifluorescence reactions for digital RNA quantification. The EZ-READ platform thus enables programmable and reliable RNA detection, across different-sized RNA subtypes (miRNA and mRNA), directly in sample lysates. When clinically evaluated, the EZ-READ platform established composite signatures for accurate blood-based GBM diagnosis and subtyping.

Rationally design and chemical modification: Getting a new and efficient biocatalyst for Henry reaction.

A robust biocatalyst for green Henry reaction was achieved. Based on the fact that Henry reaction requires a base for proton transfer, we firstly proposed that the catalytic triad of lipase could play this role. The distance between the substrate and the catalytic center and the surrounding amino acid interaction network were used as the criterion. Benzaldehyde and nitromethane were used as the model reaction, RNL (Lipase from Rhizopus niveus) was considered to be the best Henry reaction catalyst via a molecular dynamics simulation. Then experiments demonstrated that RNL has a yield of 48 % using model substrate in water. Further, in order to increase product yield, the chemical modifier 1, 2-cyclohexanedione (CHD) was used to modify Arg on RNL. As a result, RNL (CHD) increased the activity of catalyzing Henry reaction and had a broad spectrum of substrates, the yield of the product was as high as 67-99 %.