Disease relevance of ADRA1B

• Thus, ADRA1B promoter is frequently methylated in gastric cancer [1].
• In colorectal cancers, only four of 34 (11.8%) tumours showed ADRA1B promoter methylation [1].
• The frequency of ADRA1B promoter methylation was higher in gastric epithelial tissues with intestinal metaplasia (41.6%) than in those without intestinal metaplasia (25.0%) [1].
• As norepinephrine is a potent hepatocyte comitogen through binding to the alpha 1-adrenergic receptor, we have examined mRNA levels of the alpha 1a- and alpha 1b-adrenergic receptor subtypes in normal and regenerating rat hepatocytes as well as in several different rat hepatoma cell lines [2].
• A. Al Khayer, I. Sedki and K. Adra on "Painless reduction of anterior shoulder dislocation by Kocher's method" [3].

High impact information on ADRA1B

• Glucocorticoids induce transcription and expression of the alpha 1B adrenergic receptor gene in DTT1 MF-2 smooth muscle cells [4].
• Steady-state values of alpha 1B adrenergic receptor mRNA, analyzed by Northern blotting, increased 2.8 +/- 0.7-fold after 48 h exposure to dexamethasone [4].
• In addition, when the alpha 1B-adrenergic receptor was coexpressed with hH1, the alpha-receptor agonist methoxamine reduced hH1 current (45 +/- 10%), an effect that could be eliminated by chelerythrine preincubation [5].
• The adaptor complex 2 directly interacts with the alpha 1b-adrenergic receptor and plays a role in receptor endocytosis [6].
• Phospholipase Cdelta1 is a guanine nucleotide exchanging factor for transglutaminase II (Galpha h) and promotes alpha 1B-adrenoreceptor-mediated GTP binding and intracellular calcium release [7].

Biological context of ADRA1B

• For both ADRA1A and ADRA1B, haplotype superstructures may represent a novel, higher-level hierarchy in the human genome, which may reduce redundancy of testing by further aggregation of genotype data [8].
• To investigate the generality of 3i domain-induced inhibition of receptor activity further, the 3i domains of two Gq-coupled receptors (alpha 1BAR and M1AChR) and two Gi-coupled receptors (alpha 2AAR and M2AChR) were tested for effects on the second messenger generation mediated by each of the four receptors [9].
• Localization on different human chromosomes provides evidence that the bovine cDNA is distinct from the hamster alpha 1B-adrenergic receptor [10].
• Even though alpha 1C- and alpha 1BARs activate polyphosphoinositide hydrolysis by similar biochemical mechanisms, the alpha 1CAR couples to phospholipase C more efficiently than does the alpha 1BAR; activation of the alpha 1CAR results in a 2-3-fold greater increase in inositol phosphates, compared with the alpha 1BAR [11].
• Constitutive activation of the alpha 1B-adrenergic receptor by all amino acid substitutions at a single site. Evidence for a region which constrains receptor activation [12].

Anatomical context of ADRA1B

• Likewise, the human neuronal SK-N-MC cell line, classically thought to express pharmacological alpha 1AAR and alpha 1BAR subtypes, expresses both alpha 1a/dAR and alpha 1cAR mRNA and no alpha 1bAR mRNA [13].
• Coupling of the expressed alpha 1B-adrenergic receptor to the phospholipase C pathway in Xenopus oocytes. The role of Go [14].
• The pharmacological profile of cloned and stably expressed alpha 1b-adrenoceptor in CHO cells [15].

Associations of ADRA1B with chemical compounds

• We examined the effects of dexamethasone on the expression of the alpha 1B adrenergic receptor gene in DDT1 MF-2 smooth muscle cells [4].
• Similarly, expression of the 3i domain of D1ADR (D1A3i) inhibited D1ADR-mediated cAMP production but did not affect alpha 1BAR-mediated inositol phosphate accumulation [9].
• Cycloheximide induces the alpha 1B adrenergic receptor gene by activation of transcription in DDT1 MF-2 smooth muscle cells [16].
• 3. At the alpha 1B-adrenoceptor of the rat spleen and rabbit corpus cavernosum penis, tamsulosin again acted as a competitive antagonist but with a significantly lower affinity (pKB = 8.9-9.2) [17].
• This shift is 100 fold less than that previously shown to be produced by chlorethylclonidine under the same conditions on alpha 1B-adrenoceptor-mediated contractions [18].

Other interactions of ADRA1B

• First, ADRA1B is on 5q but is several million bases, rather than a few hundred thousand bases, from ADRB2 [19].
• In stellate cells, besides a strong label of alpha 2a adrenergic receptor mRNA in all and moderate label of alpha 2b message in select stellate cells, the inner stellate cells are also moderately positive for alpha 1b adrenergic receptor mRNA [20].
• Compared to the alpha 1bAR, the alpha 1aAR has several more cis regulatory elements, suggesting more complex regulation [21].
• Although the alpha 1B2i domain had no effect on receptor/G protein coupling for any receptor tested, the alpha 1B3i domain inhibited signaling mediated by alpha 1BAR and M1AChR but not by D1ADR, while the alpha 1B4i domain inhibited signaling mediated by each of the receptors [9].
• The RNase protection assay confirmed the absence of the alpha 1b adrenoceptor, the ratio of alpha 1a and alpha 1d being 4:1 [22].

Analytical, diagnostic and therapeutic context of ADRA1B

• Molecular modeling of the alpha 1a and alpha 1b-adrenergic receptor subtypes and computational simulation of receptor dynamics were useful to interpret the experimental findings derived from site directed mutagenesis studies [23].
• Southwestern blots for detection of a DNA binding protein recognizing the alpha 1B-adrenergic receptor gene promoter [24].

References