Figure 6.

Changing the length of RNA within the ARC junctions J1 and J4 decreases telomerase activity in vitro. (A) Expanded view of the yeast telomerase RNA junction sequences. Nucleotides that are universally conserved among an alignment of 36 sequences from 7 Saccharomyces species are indicated in bold (see also Supplementary Figure S6). The inset in J3 shows sequences that are present in Mini-T(460) but not in Micro-T(170). Arrows indicate the location of insertions; sequences of insertions and substitutions are listed in Supplementary Figure S1. (B, C) Deletions and insertions in the ARC result in decreased telomerase activity. Standard in vitro telomerase activity assays with deletion (Δ), insertion (i), and sequence substitution (s) mutations in Micro-T(170) (B) and Mini-T(460) (C). Superscripts indicate the number of nucleotides that were deleted or inserted at a given location. Quantitation of two independent biological replicates is indicated, as in Figure 2.