Extended Data Fig. 8: RFP repression assays reveal variable abilities of TldR homologs to block transcription elongation.
From: TnpB homologues exapted from transposons are RNA-guided transcription factors
a, RFP repression activity was measured (right) as in Fig. 4f,g using modified gRNAs exhibiting variable complementarity to the target site, as schematized in the grid (left). A gRNA was also tested that lacked the extra 5′ sequence which was absent in RIP-seq reads of mature gRNAs (20 nt no 5′ seq). Bars indicate mean ± s.d. (n = 3 biological replicates). b, Schematic of RFP repression assay in which gRNAs were designed to target either the top or bottom strand within the 5′ UTR of RFP, downstream of the promoter. The phylogenetic trees (right) indicate the relatedness of the tested and labeled homologs. c, Bar graphs plotting normalized RFP fluorescence for the indicated conditions and TldR homologs. EV, empty vector; NT, non-targeting guide. Results with nuclease-dead dCas12 and dCas9 are shown for comparison. Bars indicate mean ± s.d. (n = 3 biological replicates for TldR; n = 6 biological replicates for dCas12/dCas9).
