International Scholarly Research Notices

Review Article

Neuronal Nicotinic Receptors in Sleep-Related Epilepsy: Studies in Integrative Biology

Table 2

Functional properties of mutant nAChRs linked to sleep-related epilepsy.
MutantCloneCell typeγ   Potentiation by Sensitivity to ACh References
HomoHet HomoHetHomo Het
α4-S248FHumanXenopus nd ndndndndnd nond↓ ↓[248, 250, 251]
HumanXenopus ↓↓nd↓ ↓ndnd nond↓ ↓[249]
Human Xenopus nd↓no ↓ndnd ↑↑↑↓ ↓[252, 253]
RatXenopus ↓↓nd ↓ ↓nd nond↓ ↓[254–257]
α4-S252LHuman
Xenopus nd
↓
no
no
nd
nd
↑↑
↑↑
↓
[252, 253]
RatXenopus ndnondndndnd(↑)nd↓[254]
RatXenopus ndndnd nd↓↓nond↓[256, 257]
α4-776ins3HumanXenopus ndnono↓↓nd↑↑↑↑ ↑ [225, 250, 252, 253]
RatXenopus (↑)nond↓↓↓nond no [254, 256, 257]
α4-T265IHumanXenopus nd(↓)(↓)ndndnd ↑↑ no [228, 253]
β2-V287LHuman HEK no*↓nono↓ * no*(↑)nd ↑↑ [164]
RatXenopus (↓)ndndnd↓nd(↑)nd no[256, 257]
β2-V287MHumanXenopus nd↓ ↓nondndnd ↑↑↑↑ no [165, 252]
  HEKno        [231]
RatXenopus ndndndnd↓↓(↑)nd no [256, 257]
β2-I312MHumanXenopus ndnd↑↑nd nd↑↑ ↑↑ no [230]
β2-L301VHumanXenopus nd↑↑↑↑ nd nd↑↑ no[231]
HEK/GH4-C1no       no 
β2-V308AHumanXenopus nd ↑↑ nd nd↑↑ no[231]
HEK/GH4-C1no       no 
α2-I279NHuman HEK (with β4)no*nonond nd↑↑↑ no[21, 245]
Xenopus (with β2)ndndndnd nd↑↑↑ no[246]
Legend: γ: single-channel conductance; homo: homozygous condition; hetero: heterozygous condition; : current measured in the presence of saturating agonist concentrations; nd: not determined; : permeability to Ca2+; : monoexponential time constant of desensitization; ↑: increase; (↑): small increase; ↑↑: strong increase; ↓: decrease; (↓): small decrease; ↓ ↓: strong decrease. *A. Becchetti and C. Di Resta, unpublished results.