Age- and diapause-related acid and alkaline phosphatase activities in the intestine and Malpighian tubules of the Colorado potato beetle, Leptinotarsa decemlineata (Say)

Specific activities for soluble (s) and membrane (m)-bound acid (ACP) and a lkaline phosphatases (ALP) were determined in the midgut, hindgut, and Malp ighian tubules for developing, prediapausing, and diapausing adult Colorado potato beetles, Leptinotarsa decemlineata (Say). High ACP activities were found in the hindgut and Malpighian tubules while high ALP activities were found in the Malpighian tubules. Variation in both ACP and ALP activities i n each tissue reflects fluctuation in protein synthesis and secretion invol ved with digestion, excretion, and other unknown functions. Phosphatase act ivities in the tissues examined show the dynamic nature of diapause in this insect. Diapausing beetles showed increases in phosphatase activity after hormone treatments. JHA treatments increased s-ACP and m-ACP activities in all tissues but 20-HE did not increase activity in any tissue. Allatotropin tended to mimic the effects of JHA treatment. The s-ALP activity was also increased in all tissues whereas m-ALP was increased in the midgut and hind gut by JHA treatment. Malpighian tubule m-ALP activity was only increased b y 20-HE treatments. Allatotropin was not as effective in increasing ALP act ivities as it was with ACP activities.. (C) 2001 Wiley-Liss, Inc.(dagger)