UTP

In the event of peripheral nerve injury, the axons and myelin sheaths of the distal portion of the nerve stump are removed after injury in a process known as Wallerian degeneration. Wallerian degeneration is characterized by a series of molecular and cellular events that work together to establish a microenvironment for nerve regeneration. Schwann cells (SCs) are critical to both Wallerian degeneration and the regeneration process. SCs can assume a reparative phenotype after injury and are thereby capable of proliferating, migrating, and re-orienting axonal growth. Researchers observed that UTP promotes maintenance of the denervated state of SCs by blocking two of the most important axon-derived signaling pathways. UTP treatment reduces cAMP-dependent KROX-20 upregulation and NRG signaling through ErbB3 receptors. UTP also inhibited the expression of N-cadherin at SC-axon contact sites and promotes an undifferentiated phenotype more prone to migration.

Fig. 1 UTP action on cultured Schwann cells in peripheral nerve regeneration. (Marta Palomo-Guerrero.; et al. 2018)

RNA is an important biochemical molecule. RNA lesion, such as RNA with non-alkaline sites (AP-RNA), can lead to severe adverse consequences. Therefore, the efficient and sensitive detection of AP-RNA is of significant interest. Zhao et al. used a wet chemical method to prepare water-soluble uridine triphosphate (UTP)-coated manganese-doped zinc sulfide quantum dots (QDs), which had good room-temperature phosphorescence (RTP) properties. The uridine triphosphate on the quantum dot surface can form a precipitate complex with amiloride (AMI), and thus quench its RTP. At the same time, double-stranded RNA with non-alkaline sites (AP-dsRNA), which has a high affinity for AMI, can promote the dissociation of AMI from the UTP-QDs surface and recover its RTP. In this sensing mechanism, a highly sensitive and selective RTP detection system for AP-dsRNA was constructed. AMI acted as the modulator and UTP-QDs served as the luminescent substrate. During the detection of AP-dsRNA, the RTP signal is turned off and on, which can effectively avoid the interference of background fluorescence and scattered light by means of complex and aggregation formation.

Fig. 2 (A)Schematic diagram of UTP-QDs synthesis. (B) Mechanism of AP-dsRNA detection using UTP-QDs RTP modulated byAMI.(Jie Zhao.; et al. 2022)