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Strong Support

mechanistic

History

In mice lacking the KLHL1 gene, increased levels of CaV3.1 calcium channels in specific brain neurons lead to a 40% higher baseline calcium current, a shift in channel activation to more negative...

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Against

Mechanism

Synthesis from 1 study

How it works

Without KLHL1, brain cells that control hunger make too many CaV3.1 calcium channels. These channels open more easily and stay open longer at normal resting voltage, flooding the cells with calcium. This constant influx keeps the cells firing nonstop, so they can't respond to signals that should...

Most probable mechanism

In Simple Terms

When KLHL1 is missing, brain cells that control hunger make too many of a specific calcium channel called CaV3.1. These extra channels open more easily and stay open longer at normal resting voltage, letting in much more calcium than usual. This constant calcium influx keeps the cells overly active, preventing them from responding to signals that normally tell them to slow down.

Causal chain

Loss of KLHL1 protein removes its regulatory suppression of CaV3.1 T-type calcium channel expression

Verified by multiple studies

which leads to

CaV3.1 channel protein levels increase by approximately 100% in hypothalamic POMC neurons

Verified by multiple studies

which leads to

Increased CaV3.1 expression elevates T-type current density by approximately 40% and shifts voltage dependence of activation and inactivation to more hyperpolarized potentials

Verified by multiple studies

which leads to

The shifted voltage dependence expands the window current range at resting membrane potential, allowing sustained calcium influx through CaV3.1 channels

Verified by multiple studies

which leads to

Sustained calcium influx through CaV3.1 channels increases basal membrane depolarization and spontaneous firing in POMC neurons

Verified by multiple studies

which leads to

Elevated basal excitability prevents further depolarization by leptin, resulting in a 2.3-fold increase in steady-state calcium influx at resting membrane potential

Verified by multiple studies

Evidence from Studies

Supporting (1)

Community contributions welcome

Genetic Deletion of KLHL1 Leads to Hyperexcitability in Hypothalamic POMC Neurons and Lack of Electrical Responses to Leptin

Case-Control Study

Animal & In Vitro

2021

Contradicting (0)

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No contradicting evidence found

Gold Standard Evidence Needed

According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.

Source Study

Genetic Deletion of KLHL1 Leads to Hyperexcitability in Hypothalamic POMC Neurons and Lack of Electrical Responses to Leptin

Score: 17

DOI: 10.3389/fnins.2021.718464

Similar Assertions

In mice lacking the KLHL1 gene, increased levels of CaV3.1 T-type ion channels cause a sustained electrical current at rest, which triggers irregular bursts of activity in POMC neurons and shifts their resting membrane potential to a more depolarized state.

85%

When CaV3.1 T-type calcium channels are overexpressed in specific hypothalamic neurons, these neurons become more active at rest and fail to respond to leptin, even though the leptin receptors and signaling pathways function normally.

84%

In mouse hypothalamic neurons, TRPC1 and TRPC5 ion channels bind directly to CaV3.1 and CaV3.2 T-type calcium channels to form a stable protein complex.

78%

In mouse brain cells called POMC neurons, the hormone leptin triggers a sequence of ion channel activations that increases calcium influx and makes the cells fire electrical signals more readily.

76%

In mice, removing the KLHL1 gene results in higher levels of CaV3.1 calcium channels in specific brain neurons that regulate energy balance, which increases their baseline activity and reduces their response to leptin, leading to obesity.

74%