Fig. 1.

Schematic representation of main pathways involved in PCH. a schematic representation of tRNA splicing by TSEN complex and CLP1. b charging of Arg-related tRNA by RARS2. c) the conversion of O-phosphoseryl-tRNA(Sec) to selenocysteinyl-tRNA by SepSecs. d) exosome complex: the structural cap including EXOSC1-3, the core ring including EXOSC4-9, and the catalytic unit made up of DIS3 protein. e) Processing of immature 3’-tailed human telomerase RNA component (hTR) to mature 451nt hTR. f) structure of the human spliceosome prior to exon ligation. PRP17 and PPIL1 are shown by arrows