Search results for "Subunit"
showing 10 items of 513 documents
Gene structure and hemocyanin isoform HtH2 from the mollusc Haliotis tuberculata indicate early and late intron hot spots.
2002
Abstract We have cloned and sequenced cDNAs coding for the complete primary structure of HtH2, the second hemocyanin isoform of the marine gastropod Haliotis tuberculata. The deduced protein sequence comprises 3399 amino acids, corresponding to a molecular mass of 392 kDa. It shares only 66% of structural identity with the previously analysed first isoform HtH1, and according to a molecular clock, the two isoforms of Haliotis hemocyanin separated ca. 320 million years ago. By genomic polymerase chain reaction and 5′ race, we have also sequenced the complete gene of HtH2 (18,598 bp), except of the 5′ region in front of the secreted protein. It encompasses 15 exons and 14 introns and shows se…
HIF-1α induces MXI1 by alternate promoter usage in human neuroblastoma cells
2009
Adaptation to low oxygen conditions is essential for maintaining homeostasis and viability in oxygen-consuming multi-cellular tissues, including solid tumors. Central in these processes are the hypoxia-inducible transcription factors, HIF-1 and HIF-2, controlling genes involved in e.g. glucose metabolism and neovascularization. Tumor hypoxia and HIF expression have also been associated with a dedifferentiated phenotype and increased aggressiveness. In this report we show that the MAX interactor-1 (MXI1) gene is directly regulated by HIF proteins in neuroblastoma and breast cancer cells. HIF-binding and transactivation were detected within MXI1 gene regulatory sequences in the vicinity of th…
The diversity of GABAA receptors. Pharmacological and electrophysiological properties of GABAA channel subtypes.
1998
The amino acid gamma-aminobutyric-acid (GABA) prevails in the CNS as an inhibitory neurotransmitter that mediates most of its effects through fast GABA-gated Cl(-)-channels (GABAAR). Molecular biology uncovered the complex subunit architecture of this receptor channel, in which a pentameric assembly derived from five of at least 17 mammalian subunits, grouped in the six classes alpha, beta, gamma, delta, sigma and epsilon, permits a vast number of putative receptor isoforms. The subunit composition of a particular receptor determines the specific effects of allosterical modulators of the GABAARs like benzodiazepines (BZs), barbiturates, steroids, some convulsants, polyvalent cations, and et…
Hemocyanin subunit organization of the gastropod Rapana thomasiana
1999
Abstract RtH1 and RtH2, the two hemocyanin isoforms of the prosobranch gastropod Rapana thomasiana, have been purified by anion-exchange chromatography and studied by SDS–PAGE and immunoelectrophoresis. Both subunit types are built up of eight functional units (FUs). Under reducing conditions subunit RtH2 splits into two fragments, RtH2- a – f and RtH2- gh, suggesting the presence of a disulfide bridge between FU2- f and FU2- g. By proteolytic cleavage of the subunits into three-, two-, and single-FU fragments, purification of fragments by HPLC, N-terminal sequencing of the peptides, and crossed-line immunoelectrophoresis, FUs- a – h of RtH2 and FU- a, FU- d, FU- e, and FU- f of RtH1 were i…
Association of Whirlin with Cav1.3 (α1D) Channels in Photoreceptors, Defining a Novel Member of the Usher Protein Network
2010
Contains fulltext : 88383.pdf (Publisher’s version ) (Closed access) PURPOSE: Usher syndrome is the most common form of hereditary deaf-blindness. It is both clinically and genetically heterogeneous. The USH2D protein whirlin interacts via its PDZ domains with other Usher-associated proteins containing a C-terminal type I PDZ-binding motif. These proteins co-localize with whirlin at the region of the connecting cilium and at the synapse of photoreceptor cells. This study was undertaken to identify novel, Usher syndrome-associated, interacting partners of whirlin and thereby obtain more insights into the function of whirlin. METHODS: The database of ciliary proteins was searched for proteins…
Human complement C81 (C8 A) polymorphism: detection and segregation of new variants
1993
In addition to the earlier detected C81(A) rare variants A1, A2 (now A3) and B1 (now B2), six new rare variants (C81 A2 new, A4, A5, A6, M1 and B1new) are described within the polymorphism of the eighth component of human complement (alpha-gamma chain subunit). Except for A3, all rare C81 A variants are only detected by isoelectric focusing, and not by SDS polyacrylamide gel electrophoresis (PAGE), in the alpha-gamma subunit. In one individual out of approximately 700 individuals studied, a reversed position of the common allele (B vs A) was observed by SDS PAGE and the isofocusing technique. The segregation of A1, A3 and A4 could be followed in putative father/child combinations.
Hypoxia and anemia: effects on tumor biology and treatment resistance
2004
In locally advanced solid tumors, oxygen (O2) delivery is frequently reduced or even abolished. This is due to abnormalities of the tumor microvasculature, adverse diffusion geometries, and tumor-associated and/or therapy-induced anemia. Up to 50-60% of locally advanced solid tumors may exhibit hypoxic and/or anoxic tissue areas that are heterogeneously distributed within the tumor mass. In approximately 30% of pretreatment patients, a decreased O2 transport capacity of the blood as a result of tumor-associated anemia can greatly contribute to the development of tumor hypoxia. While normal tissues can compensate for this O2 deficiency status by a rise in blood flow rate, locally advanced tu…
Native-state pea albumin and globulin behavior upon transglutaminase treatment
2015
International audience; The behavior of pea albumin (Alb) and globulin (Glob) in their native state upon microbial transglutaminase (MTGase) treatment was studied. Only Glob was able to form a gel, at up to a 10% (w/w) concentration, with a minimum gelling concentration of 6% (w/w), and with a cross-linking degree of 25%. The most affected Glob subunits were convicilin (71 kDa), vicilins (55, 50, and 35 kDa), and legumin acidic subunit (40 kDa). In contrast, the legumin basic subunit (20 kDa) and vicilins of molecular weight less than 20 kDa remained mostly intact in all studied conditions. The cross-linking degree of Alb was 12%, which was not sufficient to form MTGase-induced gel. Major a…
A distinct subset of HLA-DR+-regulatory T cells is involved in the induction of preterm labor during pregnancy and in the induction of organ rejectio…
2010
Regulatory T cells (Tregs) are known to suppress alloimmune responses during pregnancy and post organ transplantation. We demonstrate that a distinct subset of FoxP3(+)DR(+)-Tregs among the total CD4(+)CD127(low+/-)CD25(+)-Treg cell pool is critically involved in preterm labor induction and kidney transplant rejection as well. Compared to healthy pregnancies and non-rejecting kidney recipients, we found that the percentage of the FoxP3(+)DR(+)-Treg subset was not reduced, but that the level of HLA-DR expression of such Tregs was strongly diminished in preterm laboring women and in patients with acute renal allograft rejection. In addition, both patient collectives showed a significantly red…
Nature of O2, CO, and CN binding to hemoprotein models
2004
Parametrization of a molecular-mechanics program to include terms specific for five- and six-coordinate transition metal complexes results in computer-simulated structures of hemo complexes. The principal new feature peculiar to five- and six-coordination is a term that measures the effect of electron-pair repulsion modified by the ligand electronegativity and takes into account the different structural possibilities. The work consists in the modification of program molecular mechanics for penta and hexacoordination. The model system takes into account the structural differences of the fixing center in the hemoglobin subunits. The customary proximal histidine is added. The macrocycle hemo I…