Tsn, or Tudor-staphylococcal/micrococcal-like nuclease, is involved in the cellular pathway of miRNA decay known as TumiD. It promotes the decay of miRNAs containing CA and/or UA dinucleotides, which is important for regulating the expression of protein-encoding transcripts, thus impacting various biological processes [1].

In T24 human urinary bladder cancer cells, the ATP-dependent RNA helicase UPF1 was found to be required for cellular TumiD. UPF1 can dissociate miRNAs from their mRNA targets, making them more susceptible to TSN-mediated degradation. This augmentation of TumiD by UPF1 promotes the invasion of T24 cells in part by degrading anti-invasive miRNAs and up-regulating pro-invasive proteins [1].

In conclusion, Tsn is a key nuclease in miRNA decay, with its function in this process being influenced by UPF1. The study of Tsn through in vitro and in vivo models, such as in T24 human urinary bladder cancer cells, helps to understand its role in cellular invasion, providing insights into cancer-related biological processes and potentially new strategies for cancer treatment.

References:

1. Elbarbary, Reyad A, Miyoshi, Keita, Hedaya, Omar, Myers, Jason R, Maquat, Lynne E. 2017. UPF1 helicase promotes TSN-mediated miRNA decay. In Genes & development, 31, 1483-1493. doi:10.1101/gad.303537.117. https://pubmed.ncbi.nlm.nih.gov/28827400/