r(HGNCGENEFAMILY:"Cholinergic receptors nicotinic subunits")
It is noteworthy that the alpha7 nAChR activity increases intracellular accumulation of Abeta in neurons (336), and Abeta peptides, in addition to modulating nAChR activity, downregulate the expression of nAChRs (197). PubMed:19126755
For example, Loring and colleagues (458) compared the relative expression of alpah4beta2 versus alpha7 nAChRs transfected into five different cell lines (GH4C1, SH-EP1, CV1, SN-56, and CHOCAR). Each cell line expressed appropriate mRNAs (indicating successful transfection); however, the relative levels of expression of each receptor subtype varied significantly among the various cell lines. PubMed:19126755
In cell lines, this interaction of trans-activating components is also under the regulation of the Ras-dependent MAPK and pathways related to phosphoinositide-3-kinase (PI3K) and MEK activation whose response to trophic factors such as nerve growth factor (NGF) contributes to regulating transcript initiation. PubMed:19126755
In cell lines, this interaction of trans-activating components is also under the regulation of the Ras-dependent MAPK and pathways related to phosphoinositide-3-kinase (PI3K) and MEK activation whose response to trophic factors such as nerve growth factor (NGF) contributes to regulating transcript initiation. PubMed:19126755
As was noted above, in different laboratories, these cells were reported to regulate nAChR mRNA expression differently in response to nerve growth factor, and to exhibit dramatically different expression of alpha7 nAChRs. PubMed:19126755
Also central to restricting (or at least limiting) the expression of these transcripts to predominantly neuronal-like cell lines (Neuro2A and NGF-treated PC12) are interactions among other factors including SCIP/Tst- 1/Oct-6 and transactivation by Sox10 (66, 268, 317, 513). PubMed:19126755
More recent approaches have confirmed this: RNA profiling of isolated neurons from control brains or brains from patients with AD show no evidence for changes in nAChR RNA (Chow et al., 1998; Ginsberg et al., 2000). PubMed:19293145
When cRNAs encoding specific nAChR subunits are introduced into Xenopus oocytes, simple (alpha3beta4) as well as more complex (muscle alpha1beta1deltagamma) heteromeric receptors are assembled and expressed on the cell surface (341). In Xenopus oocytes, these heteromeric nAChRs are assembled and expressed with almost equivalent efficiencies as the homomeric 5HT3A receptor (341). PubMed:19126755
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If you find BEL Commons useful in your work, please consider citing: Hoyt, C. T., Domingo-Fernández, D., & Hofmann-Apitius, M. (2018). BEL Commons: an environment for exploration and analysis of networks encoded in Biological Expression Language. Database, 2018(3), 1–11.