Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0033036 (APC)
 10,214 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We sought to isolate and partially purify proteins corresponding to the binding element of the imidazoline receptor (IR) from adrenal chromaffin cell membranes. These cells express IRs of the I-2 subclass and not alpha 2-adrenergic receptors. Proteins were solubilized in 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate-containing buffer and were assayed by binding of [3H]idazoxan, an imidazoline radioligand. Two ligand affinity resins, p-aminoclonidine-Trisacryl GF-2000 (PAC-ReactiGel) and idazoxan-PharmaLink agarose (IDA-agarose), were synthesized. These allowed purification by single-step affinity chromatography of a major receptor binding protein component of 70 kDa, as assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis and [3H]idazoxan binding assay. The purified imidazoline-binding proteins from IDA-agarose and PAC-ReactiGel had similar affinities for the radioligand [3H]idazoxan (Kd = 3.7 and 4.9 nM, respectively) and a displacement profile, showing sensitivity to imidazoline agents (cirazoline > clonidine) and insensitivity to catecholamines and adrenergic agents (epinephrine approximately rauwolscine), that was similar to that of the intact membrane receptor. The imidazoline-binding protein did not bind to concanavalin A, suggesting that it may not be glycosylated or that the sugar moieties present are not recognized by this lectin. The results indicate that IR and alpha 2 receptor proteins may be biochemically distinct and that IDA-agarose and PAC-ReactiGel columns are useful for purification of sufficient quantities of imidazoline-binding proteins to allow for structural and functional studies of the IR.
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PMID:Isolation and characterization of imidazoline receptor protein from bovine adrenal chromaffin cells. 143 52

Interactions between a alpha 2-adrenoceptor agonist and neuropeptide Y (NPY) binding sites have been studied in the rat medulla oblongata (MO) using biochemical binding techniques as well as quantitative autoradiography. Tritiated para-amino clonidine (3H-PAC; alpha 2-adrenoceptor agonist), idazoxan (3H-IDA; alpha 2-adrenoceptor antagonist) and iodinated neuropeptide Y (125I-NPY) were used as radioligands. (1) Neuropeptide Y (NPY; 10(-8) M) but not bovine pancreatic polypeptide (BPP) nor peptide YY (PYY 10 nM) increased the KD value of 3H-PAC binding sites. However, intraventricular administration of a high dose of NPY (1.25 nmol) did not change the 3H-PAC binding characteristics in MO membrane preparations of these animals. (2) GTP 10(-4) lowered the affinity of 3H-PAC binding. NPY (10 nM) had no additional effect, nor did NPY influence the GTP induced shift in potency of clonidine to displace 3H-IDA from its binding sites. (3) In the autoradiographical experiments NPY (10 nM) significantly reduced 3H-PAC binding (2 nM) in the nucleus tractus solitarius (NTS) area by 35%. (4) When clonidine, either given centrally in vivo (3.75 nmol) or in vitro (10 nM) the binding of 125I-NPY was reduced (34 and 24%, respectively) in the NTS. When the monoamine receptors were irreversibly blocked in vivo by N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ, 10 micrograms i.c. 24 h) 125I-NPY (0.5 nM) binding was increased by 137% in the NTS. This effect of EEDQ was prevented by pretreatment with the alpha 2-adrenoceptor antagonist idazoxan. These results provide support for a direct intramembrane interaction between the alpha 2-receptor and the NPY receptor within the NTS and may be of importance in central cardiovascular regulation.
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PMID:Reciprocal interactions between alpha 2-adrenoceptor agonist and neuropeptide Y binding sites in the nucleus tractus solitarius of the rat. A biochemic and autoradiographic analysis. 253 74

We have cloned and characterized the ida gene that is required for proliferation of imaginal disc cells during Drosophila development. IDA is homologous to APC5, a subunit of the anaphase-promoting complex (APC/cyclosome). ida mRNA is detected in most cell types throughout development, but it accumulates to its highest levels during early embryogenesis. A maternal component of IDA is required for the production of eggs and viable embryos. Homozygous ida mutants display mitotic defects: they die during prepupal development, lack all mature imaginal disc structures, and have abnormally small optic lobes. Cytological observations show that ida mutant brains have a high mitotic index and many imaginal cells contain an aneuploid number of aberrant overcondensed chromosomes. However, cells are not stalled in metaphase, as mitotic stages in which chromosomes are orientated at the equatorial plate are never observed. Interestingly, some APC/C-target substrates such as cyclin B are not degraded in ida mutants, whereas others controlling sister-chromatid separation appear to be turned over. Taken together, these results suggest a model in which IDA/APC5 controls regulatory subfunctions of the anaphase-promoting complex.
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PMID:Phenotypic characterization of Drosophila ida mutants: defining the role of APC5 in cell cycle progression. 1187 Feb 14