In the central nervous system inhibitory neurotransmission is primarily achieved through activation of receptors for gamma-aminobutyric acid (GABA). Three types of GABA receptors have been identified on the basis of their pharmacology and electrophysiology. The predominant type, termed GABAA and a recently identified type, GABAC, have integral chloride channels, whereas GABAB receptors couple t...

Rho family GTPases play important roles in a variety of cellular processes, including actin cytoskeleton reorganization, transcription activation, and DNA synthesis. Dominant negative mutants of Rho GTPases, such as T17NRac1, that block the endogenous Rho protein activation by sequestering upstream guanine nucleotide exchange factors (GEFs) have been widely used to implicate specific members of...

We have isolated a rifampicin-resistant mutant of Escherichia coli RNA polymerase that restores transcription termination in strains with a defective rho protein. In such strains, the mutant RNA polymerase terminates transcription at normally rho-dependent sites at the end of the trp operon, in bacteriophage lambda, and within the lac operon. In addition, a strain with this mutant RNA polymeras...

Rho-associated kinase (Rho-kinase), which is activated by the small GTPase Rho, regulates formation of stress fibers and focal adhesions, myosin fiber organization, and neurite retraction through the phosphorylation of cytoskeletal proteins, including myosin light chain, the ERM family proteins (ezrin, radixin, and moesin) and adducin. Rho-kinase was found to phosphorylate a type III intermedia...

Although radiation-induced bystander effects have been well described over the past decade, the mechanisms of the signaling processes involved in the bystander phenomenon remain unclear. In the present study, using the Columbia University charged particle microbeam, we found that mitochondrial DNA-depleted human skin fibroblasts (rho(o)) showed a higher bystander mutagenic response in confluent...

generalized geraghty type fuzzy mappings oncomplete metric spaces are introduced and a fixed point theorem thatgeneralizes some recent comparable results for fuzzy mappings incontemporary literature is obtained. example is provided to show thevalidity of obtained results over comparable classical results for fuzzymappings in fixed point theory. as an application, existence of coincidencefuzzy p...

The ability to control the physiological and pharmacological properties of synaptic receptors is a powerful tool for studying neuronal function and may be of therapeutic utility. We designed a recombinant adenovirus to deliver either a GABA(C) receptor rho(1) subunit or a mutant GABA(A) receptor beta(2) subunit lacking picrotoxin sensitivity [beta2(mut)] to hippocampal neurons. A green fluoresc...

We recently demonstrated that in MCF-7 breast cancer cells, insulin promoted the phosphorylation and activation of geranylgeranyltransferase I (GGTI-I), increased the amounts of geranylgeranylated Rho-A and potentiated the transactivating activity of lysophosphatidic acid (LPA) (Chappell, J., Golovchenko, I., Wall, K., Stjernholm, R., Leitner, J., Goalstone, M., and Draznin, B. (2000) J. Biol. ...

The phenotype of articular chondrocytes is dependent on the cytoskeleton, specifically the actin microfilament architecture. Articular chondrocytes in monolayer culture undergo dedifferentiation and assume a fibroblastic phenotype. This process can be reversed by altering the actin cytoskeleton by treatment with cytochalasin. Whereas dedifferentiation has been studied on chondrocytes isolated f...