| 1. |
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Chi, Gamma, et al.
(författare)
-
Cryo-EM structure of the human Kv3.1 channel reveals gating control by the cytoplasmic T1 domain
- 2022
-
Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 13:1
-
Tidskriftsartikel (refereegranskat)abstract
- Kv3 channels have distinctive gating kinetics tailored for rapid repolarization in fast-spiking neurons. Malfunction of this process due to genetic variants in the KCNC1 gene causes severe epileptic disorders, yet the structural determinants for the unusual gating properties remain elusive. Here, we present cryo-electron microscopy structures of the human Kv3.1a channel, revealing a unique arrangement of the cytoplasmic tetramerization domain T1 which facilitates interactions with C-terminal axonal targeting motif and key components of the gating machinery. Additional interactions between S1/S2 linker and turret domain strengthen the interface between voltage sensor and pore domain. Supported by molecular dynamics simulations, electrophysiological and mutational analyses, we identify several residues in the S4/S5 linker which influence the gating kinetics and an electrostatic interaction between acidic residues in alpha 6 of T1 and R449 in the pore-flanking S6T helices. These findings provide insights into gating control and disease mechanisms and may guide strategies for the design of pharmaceutical drugs targeting Kv3 channels. Here, Chi et al. report cryo-EM structures of the human Kv3.1a channel, revealing a unique arrangement of the cytoplasmic T1 domain, which allows the interactions with the C-terminal axonal targeting motif and key components of the gating machinery. These findings provide insights into the functional relevance of previously unknown interdomain interactions in Kv3 channels and may guide the design of new pharmaceutical drugs.
|
|
| 6. |
- Benjet, Corina, et al.
(författare)
-
A longitudinal study on the impact of Internet gaming disorder on self‐perceived health, academic performance, and social life of first‐year college students
- 2023
-
Ingår i: American Journal on Addictions. - : John Wiley & Sons. - 1055-0496 .- 1521-0391. ; 32:4, s. 343-351
-
Tidskriftsartikel (refereegranskat)abstract
- Background and objectives: Internet gaming disorder (IGD) is associated with health, social, and academic problems but whether these are consequences of the disorder rather than precursors or correlates is unclear. We aimed to evaluate whether IGD in the 1st year of university predicts health, academic and social problems 1 year later, controlling for baseline health, academic and social problems, demographics, and mental health symptoms.Methods: In a prospective cohort study, 1741 university students completed both a baseline online survey in their 1st year and a follow-up survey 1 year later. Log-binomial models examined the strength of prospective associations between baseline predictor variables (IGD, baseline health, academic and social problems, sex, age, and mental health symptoms) and occurrence of health, academic and social problems at follow-up.Results: When extensively adjusted by the corresponding outcome at baseline, any mental disorder symptoms, sex, and age, baseline IGD was associated only with severe school impairment and poor social life (risk ratio [RR] = 1.77; 95% confidence interval [CI] = 1.14-2.75, p = .011; RR = 1.22; 95% CI = 1.07-1.38, p = .002, respectively).Conclusions and scientific significance: University authorities and counselors should consider that incoming 1st-year students that meet criteria for IGD are likely to have increased academic and social impairments during their 1st year for which they may want to intervene. This study adds to the existing literature by longitudinally examining a greater array of negative outcomes of IGD than previously documented.
|
|
| 7. |
- Clatot, Jerome, et al.
(författare)
-
A structurally precise mechanism links an epilepsy-associated KCNC2 potassium channel mutation to interneuron dysfunction
- 2024
-
Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 121:3
-
Tidskriftsartikel (refereegranskat)abstract
- De novo heterozygous variants in KCNC2 encoding the voltage-gated potassium (K+) channel subunit Kv3.2 are a recently described cause of developmental and epileptic encephalopathy (DEE). A de novo variant in KCNC2 c.374G > A (p.Cys125Tyr) was identified via exome sequencing in a patient with DEE. Relative to wild-type Kv3.2, Kv3.2-p.Cys125Tyr induces K+ currents exhibiting a large hyperpolarizing shift in the voltage dependence of activation, accelerated activation, and delayed deactivation consistent with a relative stabilization of the open conformation, along with increased current density. Leveraging the cryogenic electron microscopy (cryo-EM) structure of Kv3.1, molecular dynamic simulations suggest that a strong π-π stacking interaction between the variant Tyr125 and Tyr156 in the α-6 helix of the T1 domain promotes a relative stabilization of the open conformation of the channel, which underlies the observed gain of function. A multicompartment computational model of a Kv3-expressing parvalbumin-positive cerebral cortex fast-spiking γ-aminobutyric acidergic (GABAergic) interneuron (PV-IN) demonstrates how the Kv3.2-Cys125Tyr variant impairs neuronal excitability and dysregulates inhibition in cerebral cortex circuits to explain the resulting epilepsy.
|
|
