Disk electrophoresis fractionation of hemolymph proteins during the metamorphosis of different castes and sexes of Formica pratensis

Using polyacrylamide electrophoresis the proteins of the haemolymph of the different developmental stages can be separated into eight strong and nine weak coloured fractions during the cocoon period of Formica pratensis. The proteins were stained with aniline black and measured quantitatively by a Chromoscan densitometer. The values were compared with those maintained with bovine serum albumin.The total protein content of the haemolymph was calculated as the sum of the different fractions; at maximum it amounts to 2·1 per cent (w/v). The maximum is reached during the pharate pupal stage and during the pigmentation of the eyes; the minimum can be observed at the end of pupal ecdysis. At the beginning of body pigmentation in all the forms the protein content of the haemolymph was very much reduced, especially in workers and females.All fractions change independently resulting in a different composition of the haemolymph proteins in pharate pupae, eclosed pupae, and pharate adults. The slow-running fractions f1, f3, f5, and f6 and the mean bands f8 and f11 are reduced weakly until body pigmentation, and from the eleventh day strongly in both castes. All fractions are reduced during the cocoon period, but mostly the slow-running ones. Only the front band f14 increases to nearly twice that of the protein content. The importance of the changes in the protein fractions for development of different organs and for the synthesis of the haemolymph proteins and the influence of hormones are discussed.