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1. The Legs Have It: In Situ Expression of Ion Transporters V-Type H + -ATPase and Na + /K + -ATPase in the Osmoregulatory Leg Organs of the Invading Copepod Eurytemora affinis

   https://doi.org/10.1086/686323  

   Gerber, Lucie ; Lee, Carol Eunmi ; Grousset, Evelyse ; Blondeau-Bidet, Eva ; Boucheker, Nesrine Boudour ; Lorin-Nebel, Catherine ; Charmantier-Daures, Mireille ; Charmantier, Guy ( May 2016 , Physiological and Biochemical Zoology)

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2. Cell death signaling in Anopheles gambiae initiated by Bacillus thuringiensis Cry4B toxin involves Na + /K + ATPase

   https://doi.org/10.1177/15353702231188072  

   Liu, Li ; Bulla, Jr, Lee A. ( August 2023 , Experimental Biology and Medicine)

   Identifying the mechanisms by which bacterial pathogens kill host cells is fundamental to understanding how to control and prevent human and animal disease. In the case of Bacillus thuringiensis (Bt), such knowledge is critical to using the bacterium to kill insect vectors that transmit human and animal disease. For the Cry4B toxin produced by Bt, its capacity to kill Anopheles gambiae, the primary mosquito vector of malaria, is the consequence of a variety of signaling activities. We show here that Cry4B, acting as first messenger, binds specifically to the bitopic cadherin BT-R₃G-protein-coupled receptor (GPCR) localized in the midgut of A. gambiae, activating the downstream second messenger cyclic adenosine monophosphate (cAMP). The direct result of the Cry4B–BT-R₃binding is the release of α_sfrom the heterotrimeric αβγ-G-protein complex and its activation of adenylyl cyclase (AC). The upshot is an increased level of cAMP, which activates protein kinase A (PKA). The functional impact of cAMP–PKA signaling is the stimulation of Na⁺/K⁺-ATPase (NKA) which serves as an Na⁺/K⁺pump to maintain proper gradients of extracellular Na⁺and intracellular K⁺. Increased level of cAMP amplifies NKA and upsets normal ion concentration gradients. NKA, as a scaffolding protein, accelerates the first messenger signal to the nucleus, generating additional BT-R₃molecules and promoting their exocytotic trafficking to the cell membrane. Accumulation of BT-R₃on the cell surface facilitates recruitment of additional toxin molecules which, in turn, amplify the original signal in a cascade-like manner. This report provides the first evidence of a bacterial toxin using NKA via AC/PKA signaling to execute cell death.

    

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3. Distinct effects of Q925 mutation on intracellular and extracellular Na+ and K+ binding to the Na+, K+-ATPase

   https://doi.org/10.1038/s41598-019-50009-2  

   Nielsen, Hang N. ; Spontarelli, Kerri ; Holm, Rikke ; Andersen, Jens Peter ; Einholm, Anja P. ; Artigas, Pablo ; Vilsen, Bente ( September 2019 , Scientific Reports)

   Three Na⁺sites are defined in the Na⁺-bound crystal structure of Na⁺, K⁺-ATPase. Sites I and II overlap with two K⁺sites in the K⁺-bound structure, whereas site III is unique and Na⁺specific. A glutamine in transmembrane helix M8 (Q925) appears from the crystal structures to coordinate Na⁺at site III, but does not contribute to K⁺coordination at sites I and II. Here we address the functional role of Q925 in the various conformational states of Na⁺, K⁺-ATPase by examining the mutants Q925A/G/E/N/L/I/Y. We characterized these mutants both enzymatically and electrophysiologically, thereby revealing their Na⁺and K⁺binding properties. Remarkably, Q925 substitutions had minor effects on Na⁺binding from the intracellular side of the membrane – in fact, mutations Q925A and Q925G increased the apparent Na⁺affinity – but caused dramatic reductions of the binding of K⁺as well as Na⁺from the extracellular side of the membrane. These results provide insight into the changes taking place in the Na⁺-binding sites, when they are transformed from intracellular- to extracellular-facing orientation in relation to the ion translocation process, and demonstrate the interaction between sites III and I and a possible gating function of Q925 in the release of Na⁺at the extracellular side.

    

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4. Two-photon pathway to ultracold ground state molecules of 23 Na 40 K

   https://doi.org/10.1088/1367-2630/17/7/075016  

   Park, Jee Woo ; Will, Sebastian A. ; Zwierlein, Martin W. ( July 2015 , New Journal of Physics)
5. K → μ + μ − as a third kaon golden mode

   https://doi.org/10.1088/1742-6596/2446/1/012034  

   Dery, Avital ( February 2023 , Journal of Physics: Conference Series)

   Abstract Recent progress has demonstrated that the K → μ + μ − decay carries clean short-distance information, attainable from a measurement of time-dependence sensitive to K L − K S interference effects. We review the ingredients that go into this proposed extraction, and discuss the sensitivity to the CKM parameter η ¯ as well as to various NP scenarios. 

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