The accurate quantification of T cell subtypes and their proportions is of great significance in cell-based biomanufacturing, diagnosis, and advanced therapy. The development and application of a cell reference material (RM) provide a solid foundation for reliable and consistent T cell quantification worldwide. However, creating a cell RM that is both accurate and practical remains a challenge.
View Article and Find Full Text PDFThe antibodies in the natural biological world utilize bivalency/multivalency to achieve a higher affinity for antigen capture. However, mimicking this mechanism on the electrochemical sensing interface and enhancing biological affinity through precise spatial arrangement of bivalent aptamer probes still pose a challenge. In this study, we have developed a novel self-assembly layer (SAM) incorporating triblock polyA DNA to enable accurate organization of the aptamer probes on the interface, constructing a "lock-and-key-like" proximity hybridization assay (PHA) biosensor.
View Article and Find Full Text PDFCharacterization and integration of the genome, epigenome, transcriptome, proteome and metabolome of different datasets is difficult owing to a lack of ground truth. Here we develop and characterize suites of publicly available multi-omics reference materials of matched DNA, RNA, protein and metabolites derived from immortalized cell lines from a family quartet of parents and monozygotic twin daughters. These references provide built-in truth defined by relationships among the family members and the information flow from DNA to RNA to protein.
View Article and Find Full Text PDFThe mTOR-dependent nutrient-sensing and response machinery is the central hub for animals to regulate their cellular and developmental programs. However, equivalently pivotal nutrient and metabolite signals upstream of mTOR and developmental-regulatory signals downstream of mTOR are not clear, especially at the organism level. We previously showed glucosylceramide (GlcCer) acts as a critical nutrient and metabolite signal for overall amino acid levels to promote development by activating the intestinal mTORC1 signaling pathway.
View Article and Find Full Text PDFMitochondria and peroxisomes are two types of functionally close-related organelles, and both play essential roles in lipid and ROS metabolism. However, how they physically interact with each other is not well understood. In this study, we apply the proximity labeling method with peroxisomal proteins and report that mitochondrial protein mitofusins (MFNs) are in proximity to peroxisomes.
View Article and Find Full Text PDFProximity labeling has been used to study protein-protein interactions and can also be used as a protein labeling tool. We developed a novel 14-amino acid peptide substrate for the proximity-labeling enzyme PafA. The N terminus of the peptide can be modified with biotin or fluorophores, which allows various chemical moieties to be ligated to the target protein.
View Article and Find Full Text PDFThe communication between cells and between cellular organelles is often controlled by the interaction of membrane proteins. Although many methods for the detection of protein-protein interactions (PPIs) exist, membrane PPIs remain difficult to detect. Here we developed a proximity-based tagging system, PUP-IT (pupylation-based interaction tagging), to identify membrane protein interactions.
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