Minium (pigment) Minium (pigment) Minium, also known as red lead, is a bright orange red pigment that was widely used in the Middle Ages for the decoration of manuscripts and for painting. It was made by roasting white lead pigment in the air; the white lead would gradually turn yellow, then into an orange lead tetroxide. The color varied depending upon how long the mineral was roasted. During the Roman Empire, the term minium could refer either to the pigment made from ground cinnabar or to the less expensive red lead. The name came from the river Minius in Iberia (now forming
Pigment dispersing factor mRNA levels, while PDF knockouts show reduced protein. Similar behavioral and molecular phenotypes are observed in loss of PDF and VIP receptors. Pigment dispersing factor Pigment dispersing factor (pdf) is a gene that encodes the protein PDF, which is part of a large family of neuropeptides. Its hormonal product, pigment dispersing hormone (PDH), was named for the diurnal pigment movement effect it has in crustacean retinal cells upon its initial discovery in the central nervous system of arthropods. The movement and aggregation of pigments in retina cells and extra-retinal cells is hypothesized to be under a split hormonal control mechanism.