Western blot analyses of the sNPF receptor expression in membranes from queens. A: Membrane preparations (100 μg of protein per lane) of brains and subesophageal ganglion (SEG) (lanes 1 and 3, labeled with B) and postpharyngeal glands (lanes 2 and 4, labeled with PG) were analyzed with anti-sNPF receptor antibodies (lanes 1 and 2) or with antigen-preabsorbed antibodies (lanes 3 and 4). Only one band (~46.2 kDa) was specifically recognized in the membranes by the anti-sNPF receptor antibodies (lane 1, arrow), and no signal was detected using antigen-preabsorbed antibodies, as was expected (lane 3). No signal was detected in the membrane proteins from the postpharyngeal glands (lanes 2 and 4). B: Membrane proteins from brains and SEG (100 μg, lane 1 and 2) and ovaries (50 μg, lanes 3 and 4) of virgin queens (VQ) and mated queens (MQ) were also analyzed with anti-sNPF receptor antibodies. Similar receptor bands (~46.2 kDa) were detected in the membrane preparations of virgin and mated queens (lanes 1 and 2, arrow). The same size band (arrow) was also detected in mated queen ovaries (lane 4), but not in those of virgin queens (lane 3). In addition, two putative receptor bands (~55.3- and 51.1-kDa, lane 4, arrowheads) were detected in the mated queen ovaries but not in those of virgin queen ovaries (lane 3). M, marker.