Biosynthesis of α and β-Ecdysones from Cholesterol outside the Prothoracic Gland in Bombyx mori

Abstract
Labeling experiments have established that cholesterol is converted into α- and β-ecdysones in isolated abdomens of silkworm larvae. Since the isolated abdomens do not contain the prothoracic glands, a doubt is cast on the long-standing principle in insect endocrinology that the prothoracic glands are the source of ecdysone secretion.