Abstract
Hyperpolarization-Activated cyclic nucleotide-gated (HCN) channels are glycoproteins N-glycosylated at a specific asparagine residue in the S5-S6 linker region. Previous reports suggested that N-glycosylation-deficient HCN2 N380Q (NQ) channels fail to properly target to the plasma membrane and are unable to form functional ion channels. HCN channels are known to homo-And hetero-oligomerize and it is not known whether HCN2-NQ subunits can oligomerize with wild type (wt) N-glycosylated subunits to form a tetrameric assembly. In the present study, homomeric NQ-mutant resulted in no current, cRNA titration experiments controlling the amount of wt-To-NQ injected into Xenopus oocytes indicated that the observed currents were consistent with a model where presence of a single nonglycosylated subunit in a tetrameric oligomer is tolerated forming functional channels. The activation voltage-dependence described by half-Activation voltage and slope factor, and the reversal potential of the wt-NQ oligomeric channels were identical to the wt only tetrameric channels. Further incorporation of the nonglycosylated subunit rendered the channels nonconductive or not incorporated into the plasma membrane.
Original language | English |
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Pages (from-to) | 998-1003 |
Number of pages | 6 |
Journal | NeuroReport |
Volume | 30 |
Issue number | 15 |
DOIs | |
Publication status | Published - 2019 |
Externally published | Yes |
Keywords
- HCN2
- N-glycosylation
- Xenopus oocyte
- binomial model
- cRNA titration
- electrophysiology
- hetero-oligomerization
ASJC Scopus subject areas
- Neuroscience(all)