Fig. 5. Quantitation of proteins expressed from hsp70-knirps transgenes demonstrates that full-length Knirps 1-429 is less abundant than Knirps 1-330. (A) Western blot analysis of embryos subjected to the same heat-shock regimen (0, 5, 10 and 20 minutes) used for analysis shown in Fig. 3 and Table 1. Asterisk marks nonspecific cross-reacting protein that was also present in lysates from non-transgenic Drosophila (presence of nonspecific band appeared to vary with batch of antibody; data not shown). Because this nonspecific band co-migrates with the 1-330 protein, the signal from the nonspecific protein (averaged from lanes 5-8) was subtracted from each of the values in lanes 1-4 to determine levels of 1-330 protein. Below, Coomassie stained gel showing equal loading. (B) Quantitation of western blots demonstrates an approximately twofold higher level of Knirps 1-330 protein at each time point than Knirps 1-429, demonstrating that the higher activity of the 1-429 is not due to higher levels of this protein. Standard deviations are shown in B for four separate gels and quantitations of the heat-shock experiment shown in A.