Inhibitory effect of the RgtA sRNA on BP3831 protein production. (A) B. pertussis Tohama I (lane 1) and its isogenic ΔrgtA (lane 2) ΔBP3831 (lane 3), ΔbvgA (lane 4), and ΔbvgAΔrgtA (lane 5) mutants were grown in SS medium to exponential phase. Samples of cell lysates equivalent to 0.1 OD600 unit were separated on 12.5% SDS-PAGE gels and analyzed by immunoblotting using anti-BP3831 antibodies. Only relevant parts of the membranes are shown. The result is a representative of three experiments. (B) Schematic representation of the putative base-pairing between the RgtA RNA and BP3831 mRNA. Nucleotides 122 to 136 of RgtA are complementary to −2 to −16 region of BP3831 mRNA containing the Shine and Dalgarno sequence (SD). Nucleotides marked with an asterisk were mutated to disrupt the possible base-pairing between the RgtA and BP3831 transcripts in the ΔbvgArgtAmut strain. (C) The effect of the mutations introduced into RgtA RNA on BP3831 protein levels. B. pertussis Tohama I ΔbvgA (lane 1), ΔbvgAΔrgtA (lane 2), and ΔbvgArgtAmut (lane 3) mutants were grown in SS medium to exponential phase. Samples of cell lysates equivalent to 0.1 OD600 unit were separated on 12.5% SDS-PAGE gels and analyzed by immunoblotting using anti-BP3831 antibodies. Only relevant parts of the membranes are shown. The result is representative of two experiments.
