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Intracellular protein trafficking is tightly regulated, and improper trafficking might be the fundamental provocateur for human diseases including neurodegeneration. In neurons, protein trafficking to and from the plasma membrane affects synaptic plasticity. Voltage-gated potassium channel 2.1 (Kv2.1) is a predominant delayed rectifier potassium (K ) current, and electrical activity patterns of dopamine (DA) neurons within the substantia nigra are generated and modulated by the orchestrated function of different ion channels. The pathological hallmark of Parkinson's disease (PD) is the progressive loss of these DA neurons, resulting in the degeneration of striatal dopaminergic terminals. However, whether trafficking of Kv2.1 channels contributes to PD remains unclear. In this study, we demonstrated that MPTP/MPP increases the surface expression of the Kv2.1 channel and causes nigrostriatal degeneration by using a subchronic MPTP mouse model. The inhibition of the Kv2.1 channel by using a specific blocker, guangxitoxin-1E, protected nigrostriatal projections against MPTP/MPP insult and thus facilitated the recovery of motor coordination. These findings highlight the importance of trafficking of Kv2.1 channels in the pathogenesis of PD.

In a sample of 455 Taiwanese upper‐secondary school students, latent variable structural equation modeling was used to test hypothesized relationships between beliefs about knowledge in science, beliefs about justification for knowing in science, and justification of knowledge claims concerning science encountered on the Internet. Results indicated that participants displayed adaptive beliefs in the tentative and evolving nature of scientific knowledge while their beliefs about justification for knowing in science seemed somewhat less adaptive. Further, their self‐reports of Internet‐specific justification of knowledge claims suggested that they did not strongly believe that science information posted on the Internet needed to be carefully evaluated. The structural equation modeling indicated that beliefs in the tentative and evolving nature of scientific knowledge had direct positive relationships with beliefs in justification by research‐based authority and justification by multiple sources in science, which, in turn, mediated the relationships between beliefs in tentative and evolving knowledge and adaptive beliefs about Internet‐specific justification of knowledge claims. Beliefs in the unambiguous, certain nature of scientific knowledge had a direct positive relationship with beliefs in justification by school‐based authority (i.e., the science teacher and the science textbook), but beliefs in justification by school‐based authority were not related to Internet‐specific justification beliefs. We highlight the unique contributions of this study to the field of epistemic belief and science education research, and its theoretical and educational implications are discussed.

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