GHR/PRLR Heteromultimer Is Composed of GHR Homodimers and PRLR Homodimers

Parallel topology of genetically fused EmrE homodimers.

EmrE is a small H+-coupled multidrug transporter in Escherichia coli. Claims have been made for an antiparallel topology of this homodimeric protein. However, our own biochemical studies performed with detergent-solubilized purified protein support a parallel topology of the protomers. We developed an alternative approach to constrain the relative topology of the protomers within the dimer so t...

Partnering between monomers of cyclooxygenase-2 homodimers.

Prostaglandin endoperoxide H synthases (PGHSs) 1 and 2 convert arachidonic acid to prostaglandin H2 in the committed step of prostanoid biosynthesis. These enzymes are pharmacological targets of nonsteroidal antiinflammatory drugs and cyclooxygenase (COX) 2 inhibitors. Although PGHSs function as homodimers and each monomer has its own COX and peroxidase active sites, the question of whether the...

Protein subunit interfaces: heterodimers versus homodimers

Protein dimers are either homodimers (complexation of identical monomers) or heterodimers (complexation of non-identical monomers). These dimers are common in catalysis and regulation. However, the molecular principles of protein dimer interactions are difficult to understand mainly due to the geometrical and chemical characteristics of proteins. Nonetheless, the principles of protein dimer int...

On the significance of Toc-GTPase homodimers.

Precursor protein translocation across the outer chloroplast membrane depends on the action of the Toc complex, containing GTPases as recognizing receptor components. The G domains of the GTPases are known to dimerize. In the dimeric conformation an arginine contacts the phosphate moieties of bound nucleotide in trans. Kinetic studies suggested that the arginine in itself does not act as an arg...

Dimerization Interfaces of V-erba Homodimers and Heterodimers with Rxrα