RNAi-Mediated Gene Silencing in Trichoderma [chapter]

Xiaoyun Su, Lina Qin, Zhiyang Dong
2014 Biotechnology and Biology of Trichoderma  
tRNA fragments (tRFs) and tRNA halves have been implicated in various cellular processes, including gene silencing, translation, stress granule assembly, cell differentiation, retrotransposon activity, symbiosis, apoptosis and more. Overexpressed angiogenin (ANG) cleaves tRNA anticodons and produces tRNA halves similar to those produced in response to stress. However, it is not clear whether endogenous ANG is essential for producing the stress-induced tRNA halves. It is also not clear whether
more » ... not clear whether smaller tRFs are generated from the tRNA halves. Here, using global short RNA-Seq approach, we found that ANG overexpression selectively cleaves a subset of tRNAs, including tRNA Glu , tRNA Gly , tRNA Lys , tRNA Val , tRNA His , tRNA Asp , and tRNA SeC to produce tRNA halves and tRF-5s that are 26-30 bases long. Surprisingly, ANG knockout revealed that the majority of stress-induced tRNA halves, except for the 5' half from tRNA HisGTG and the 3' half from tRNA AspGTC , are ANG independent, suggesting there are other RNases that produce tRNA halves. We also found that the 17-25-baseslong tRF-3s and tRF-5s that could enter into Argonaute complexes are not induced by ANG overexpression, suggesting that they are generated http://www.jbc.org/cgi/
doi:10.1016/b978-0-444-59576-8.00015-1 fatcat:rrrxfycymzb7pi6i57wo4m7foe