The molecular nature and configuration of the opiate receptor is a problem under intensive investigation in a number of laboratories (1,2,3). Our interest in the problem developed as a result of a finding of others (4) that a proteolipid fraction from brain may be responsible for stereospecific opiate binding observed in various preparations of brain tissue. Upon examining various lipids, prote...

Emery-Dreifuss muscular dystrophy is a rare disorder characterized by childhood onset of contractures, humeroperoneal muscle atrophy, and cardiac conduction abnormalities. This report presents the cases of two brothers with this dystrophy in whom bilateral hypomyelination of the deep periatrial white matter was noted. In the hypomyelinated regions, a prominent peak centered at 1.5 parts per mil...

The membrane rotor ring from the vacuolar-type (V-type) sodium ion-pumping adenosine triphosphatase (Na+-ATPase) from Enterococcus hirae consists of 10 NtpK subunits, which are homologs of the 16-kilodalton and 8-kilodalton proteolipids found in other V-ATPases and in F1Fo- or F-ATPases, respectively. Each NtpK subunit has four transmembrane alpha helices, with a sodium ion bound between helice...

Chromaffin granules and clathrin-coated vesicles are major sources for V-ATPases of mammalian cells. Studies of these organelles have helped us to understand the structure and function of the enzyme. It was shown that V-ATPases are composed of distinct catalytic and membrane sectors containing several subunits. The subunit stoichiometry was determined to be 3A, 3B, 1C, 1D, 1E, 6c (proteolipids)...

Neurotransmitter release occurs at specialized areas of the nerve terminal membrane, the active zones, where clusters of synaptic vesicles, the neurotransmitter-storing organelles, are observed (Couteaux and PeÂcot-Dechavassine 1974; Harlow et al. 2001). In resting conditions, a population of synaptic vesicles is docked to the active zone membrane, close to voltage-gated calcium channels (Robit...