The node of Ranvier is a tiny segment of a myelinated fiber with various types of specializations adapted for generation of high-speed nerve impulses. It is ionically specialized with respect to ion channel segregation and ionic fluxes, and metabolically specialized in ionic pump expression and mitochondrial density augmentation. This report examines the interplay of three important parameters ...

A comparison of the effect of progesterone and DNP’ in accelerating ATPase activity in fresh rat liver mitochondria has indicated that the two may act, in a similar manner (1). Since the striking effect, of DNP on oxidative phosphorylation is probably related to its effect on mitochondrial ATPase (2, 3), an examination of the effect of progesterone on oxidative phosphorylation has been carried ...

Purified pea (Pisum sativum) cotyledon F1-ATPase contains six subunits rather than the five usually reported for F1-ATPases. The additional 26.5 kDa (delta) subunit is shown by immunoblotting and N-terminal amino acid sequencing to be similar to bovine oligomycin-sensitivity-conferring protein (OSCP). It is concluded that the delta subunit of plant mitochondrial F1-ATPase is the plant OSCP. Thi...

Modification of the mitochondrial F1-ATPase ε subunit, enhancement of the ATPase activity of the IF1–F1 complex and IF1-binding dependence of the conformation of the ε subunit Giancarlo SOLAINI*, Alessandra BARACCA†, Edi GABELLIERI‡ and Giorgio LENAZ† *Scuola Superiore di Studi Universitari e di Perfezionamento S. Anna, Via G. Carducci, 40, 56127 Pisa, Italy, †Dipartimento di Biochimica, Univer...

A large number of studies in evolutionary biology utilize phylogenetic information obtained from mitochondrial DNA. Researchers place trust in this molecule and expect it generally to be a reliable marker for addressing questions ranging from population genetics to phylogenies among distantly related lineages. Yet, regardless of the phylogenetic method and weighting treatment, individual mitoch...

Divalent cations play an important role in the functions of biomembranes. This review deals with three topics: (1) Mg(2+)-mediated change in physical state of phospholipid induces conformation and activity change of reconstituted mitochondrial H(+)-ATPase, (2) a proper transmembrane Ca2+ gradient is essential for the higher enzymatic activity of adenylate cyclase, and (3) role of transmembrane ...