Laccase, catalase, RfEst3 esterase, and β actin (as a control) gene expression in Reticulitermes flavipes worker guts as determined from 35 cycles of conventional polymerase chain reaction (PCR) amplification. Shown is a negative image of a representative agarose gel with equal loadings of PCR products for the four genes. Lane labels are as follows: FG, foregut plus salivary gland; MG, midgut; HG, hindgut; and (-), no template control. Two primer sets were tested for the laccase and catalase genes, and one primer set for esterase and β actin. A 100 base pair (bp) low molecular weight ladder (LML) is shown at the left and right. See Additional file 9 for PCR primer sequences.