LRRC8A reduces intracellular chloride to permit WNK activation in response to hypertonic stress

Goldsmith, Elizabeth J.; Huang, Chou‐Long

doi:10.1073/pnas.2109432118

Cited by 4 publications

(6 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Osmotic activation accomplished by hyperosmotic pipette solution, as used in our experiments and in classical VRAC studies [51], is consistent with the activation of lysine deficient protein kinases (WNKs), ancient cytoplasmic regulatory scaffolds sensitive to low [Cl − ] and hyperosmotic cytoplasmic conditions [52]. For WNKs to be able to orchestrate regulatory volume increase in mammalian cells, there is an absolute requirement for functional VRAC to be present [53].…”

Section: Discussionsupporting

confidence: 69%

Osmotically Activated Anion Current of Phycomyces Blakesleeanus—Filamentous Fungi Counterpart to Vertebrate Volume Regulated Anion Current

Stevanović

Čepkenović

Križak

et al. 2023

JoF

View full text Add to dashboard Cite

Studies of ion currents in filamentous fungi are a prerequisite for forming a complete understanding of their physiology. Cytoplasmic droplets (CDs), obtained from sporangiophores of Phycomyces blakesleeanus, are a model system that enables the characterization of ion currents in the native membrane, including the currents mediated by the channels not yet molecularly identified. Osmotically activated anionic current with outward rectification (ORIC) is a dominant current in the membrane of cytoplasmic droplets under the conditions of hypoosmotic stimulation. We have previously reported remarkable functional similarities of ORIC with the vertebrate volume regulated anionic current (VRAC), such as dose-dependent activation by osmotic difference, ion selectivity sequence, and time and voltage dependent profile of the current. Using the patch clamp method on the CD membrane, we further resolve VRAC-like ORIC characteristics in this paper. We examine the inhibition by extracellular ATP and carbenoxolone, the permeation of glutamate in presence of chloride, selectivity for nitrates, and activation by GTP, and we show its single channel behavior in excised membrane. We propose that ORIC is a functional counterpart of vertebrate VRAC in filamentous fungi, possibly with a similar essential role in anion efflux during cell volume regulation.

show abstract

Section: Discussionsupporting

confidence: 69%

Osmotically Activated Anion Current of Phycomyces Blakesleeanus—Filamentous Fungi Counterpart to Vertebrate Volume Regulated Anion Current

Stevanović

Čepkenović

Križak

et al. 2023

JoF

View full text Add to dashboard Cite

show abstract

“…Th activity center of WNKs contains many water molecules. Osmotic pressure by extracting water from the protein shifts the equilibrium to the latter state (Figure 12A) (43)(44)(45). During the revision of the manuscript, a paper reported that hypertonicity induces molecular crowding and phase separation on WNK1 leading to activation of WNK1-OSR1/SPAK pathway (46).…”

Section: Discussionmentioning

confidence: 99%

“…The intracellular Cl – concentration rises initially during cell shrinkage and subsequently from NKCC1-mediated Cl – entry during RVI ( 45 ). How do cells balance the two opposing forces on WNK kinase activity, i.e., inhibition by the high intracellular Cl – concentration and activation by dehydration?…”

Section: Discussionmentioning

confidence: 99%

“…Serra et al recently reported that hyperosmolality activates the LRRC8A-containing Cl – channel ( 49 ). It is proposed that Cl – efflux through the channel blunts the rise in cellular Cl – concentration, permitting hyperosmolality-induced cellular dehydration to activate WNK kinase cascade and RVI ( 45 , 49 ). Lack of RVI in the central osmosensory neurons will diminish NKCC1-mediated Cl – entry.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

WNK1 promotes water homeostasis by acting as a central osmolality sensor for arginine vasopressin release

Jin¹,

Xie²,

Yeh³

et al. 2023

Journal of Clinical Investigation

Self Cite

View full text Add to dashboard Cite

Maintaining internal osmolality constancy is essential for life. Release of arginine vasopressin (AVP) responding to hyperosmolality is critical. Current hypotheses for osmolality sensors in circumventricular organs of the brain (CVOs) focus on mechanosensitive membrane proteins. The present study demonstrated that an intracellular protein kinase WNK1 was involved. Focusing on vascular-organ-of-lamina-terminalis (OVLT) nuclei, we showed that WNK1 kinase was activated by water restriction. Neuronal-specific knockout (cKO) of Wnk1 caused polyuria with decreased urine osmolality that persisted in water restriction and blunted water restriction-induced AVP release. Wnk1-cKO also blunted mannitol-indued AVP release but had no effect on osmotic thirst response. The role of WNK1 in the osmosensory neurons in CVOs was supported by neuronal pathway tracing. Hyperosmolality-induced increases in action potential firing in OVLT neurons was blunted by Wnk1 deletion or pharmacological WNK inhibitors. Knockdown of Kv3.1 channel in OVLT by shRNA reproduced the phenotypes. Thus, WNK1 in osmosensory neurons in CVOs detects extracellular hypertonicity and mediates the increase in AVP release by activating Kv3.1 and increasing action potential firing from osmosensory neurons.

show abstract

“…WNK1 is known to be activated under hypertonic stress (51,52), and also under hypotonic stress (53,54). All these data are mostly retrieved in short-term osmotic stress experiments (minutes), whereas our osmotic stress assays were done for longer times (days).…”

Section: Inactivation Of Wnk1 Leads To Microtubule Stabilization Modi...mentioning

confidence: 99%

Osmotic Stress Influences Microtubule Drug Response Via WNK1 Kinase Signaling

Monfort-Vengut,

Sanz-Gómez,

Ballesteros-Sánchez

et al. 2024

Preprint

View full text Add to dashboard Cite

Ion homeostasis is critical for numerous cellular processes, and disturbances in ionic balance underlie diverse pathological conditions, including cancer progression. Targeting ion homeostasis is even considered as a strategy to treat cancer. However, very little is known about how ion homeostasis may influence anticancer drug response. In a genome-wide CRISPR-Cas9 resistance drug screen, we identified and validated the master osmostress regulator WNK1 kinase as a modulator of the response to the mitotic drug rigosertib. Osmotic stress and WNK1 inactivation lead to an altered response not only to rigosertib treatment but also to other microtubule-related drugs, minimizing the prototypical mitotic arrest produced by these drugs. This effect is due to an alteration in microtubule stability and polymerization dynamics, likely maintained by fluctuations in intracellular molecular crowding upon WNK1 inactivation. This promotes resistance to microtubule depolymerizing drugs, and increased sensitivity to microtubule stabilizing drugs. In summary, our data proposes WNK1 osmoregulation activity as a biomarker for microtubule-associated chemotherapy response.

show abstract

LRRC8A reduces intracellular chloride to permit WNK activation in response to hypertonic stress

Abstract: See companion article, "LRRC8A-containing chloride channel is crucial for cell volume recovery and survival under hypertonic conditions," 10.1073/ pnas.2025013118.

Cited by 4 publications

References 22 publications

Osmotically Activated Anion Current of Phycomyces Blakesleeanus—Filamentous Fungi Counterpart to Vertebrate Volume Regulated Anion Current

Osmotically Activated Anion Current of Phycomyces Blakesleeanus—Filamentous Fungi Counterpart to Vertebrate Volume Regulated Anion Current

WNK1 promotes water homeostasis by acting as a central osmolality sensor for arginine vasopressin release

Osmotic Stress Influences Microtubule Drug Response Via WNK1 Kinase Signaling

Contact Info

Product

Resources

About