Figure 1. Co-immunoprecipitation of chromosomally tagged Hfq and bound RNA. Wild-type and C-terminally tagged-Hfq strains (3xFlag or HA) were grown to exponential phase. Cell lysates were subjected to immunoprecipitation using anti-Flag or anti-HA-coupled beads. Cell lysates (input) and immunoprecipitated fractions (anti-Flag and anti-HA) were separated on 12% SDS-PAA gel. (A) Proteins were transferred onto a nitrocellulose membrane and immuno-blotted with anti-Flag or anti-HA antibody or (B) visualized by Silver staining. Bands corresponding to 3xFlag- (*) and HA-Hfq (#) are indicated. (C) Cells with C-terminally tagged Hfq bearing either 3xFlag or HA, hfq deletion and isogenic wild-type cells were grown to exponential (E) and stationary phase (S). Cell lysates were separated on an 8% SDS-PAA gel, transferred onto a nitrocellulose membrane and immuno-blotted with anti-RpoS antibody. (D) Equal amounts of co-immunoprecipitated RNA were analyzed by chip-based capillary electrophoresis.