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Fig. 2. Localization of chitin synthase in the epiproct of Periplaneta
americana. (A) Cryosections of 10µm were stained with a polyclonal
antiserum raised against a conserved region of the Manduca sexta
chitin synthase as described previously
(Zimoch and Merzendorfer,
2002). Visualization of primary antibodies was conducted with
anti-rabbit antibodies (whole molecules) conjugated to alkaline phosphatase.
Detection with 5-bromo-4-chloroindolylphosphate and nitroblue tetrazolium was
carried out in the presence of 2 mmol l-1 levamisole to block
endogenous alkaline phosphatase activity. (B) Control reaction performed in
the absence of primary antibodies. Arrows in A and B mark the apical region of
epidermal cells, which are in part detached from the endocuticle as a result
of the sectioning procedure (asterisks). Scale bar, 50µm.