Pacheco Álvarez, Diana
Thumbnail Image
Preferred name
Pacheco Álvarez, Diana
Official Name
Pacheco Álvarez, Diana
Alternative Name
dpacheco
Main Affiliation
ORCID
Scopus Author ID
14827257500
Researcher ID
DVP-2845-2022

Research Output

Filters

2
2
2
Reset filters

Settings
Now showing 1 - 2 of 2
No Thumbnail Available
Publication

WNK-SPAK-NCC cascade revisited: WNK1 stimulates the activity of the Na-Cl cotransporter via SPAK, an effect antagonized by WNK4

2014 , Chávez-Canales, María , Zhang, Chong , Soukaseum, Christelle , Moreno, Erika , Pacheco Álvarez, Diana , Vidal-Petiot, Emmanuelle , Castañeda-Bueno, María , Vázquez, Norma , Rojas-Vega, Lorena , Meermeier, Nicholas P. , Rogers, ,Shaunessy , Jeunemaitre, Xavier , Yang, Chao-Ling , Ellison, David H. , Gamba, Gerardo , Hadchouel, Juliette

The with-no-lysine (K) kinases, WNK1 and WNK4, are key regulators of blood pressure. Their mutations lead to familial hyperkalemic hypertension (FHHt), associated with an activation of the Na-Cl cotransporter (NCC). Although it is clear that WNK4 mutants activate NCC via Ste20 proline-alanine-rich kinase, the mechanisms responsible for WNK1-related FHHt and alterations in NCC activity are not as clear. We tested whether WNK1 modulates NCC through WNK4, as predicted by some models, by crossing our recently developed WNK1-FHHt mice (WNK1(+/FHHt)) with WNK4(-/-) mice. Surprisingly, the activated NCC, hypertension, and hyperkalemia of WNK1(+/FHHt) mice remain in the absence of WNK4. We demonstrate that WNK1 powerfully stimulates NCC in a WNK4-independent and Ste20 proline-alanine-rich kinase-dependent manner. Moreover, WNK4 decreases the WNK1 and WNK3-mediated activation of NCC. Finally, the formation of oligomers of WNK kinases through their C-terminal coiled-coil domain is essential for their activity toward NCC. In conclusion, WNK kinases form a network in which WNK4 associates with WNK1 and WNK3 to regulate NCC. © 2014 American Heart Association, Inc.

View
No Thumbnail Available
Publication

C-terminally truncated, kidney-specific variants of the WNK4 kinase lack several sites that regulate its activity

2018 , Murillo-de-Ozores, Adrián Rafael , Rodríguez Moya, Alejandro , Bazúa-Valenti, Silvana , Leyva Ríos, Karla , Vázquez, Norma , Pacheco Álvarez, Diana , Rosa-Velázquez, Inti A. de la , Wengi, Agnieszka , Stone, Kathryn L. , Junhui, Zhang , Loffing, Johannes , Lifton, Richard P. , Chao-Ling , Yang , Ellison, David H. , Gamba, Gerardo , Castañeda-Bueno, María

WNK lysine-deficient protein kinase 4 (WNK4) is an important regulator of renal salt handling. Mutations in its gene cause pseudohypoaldosteronism type II, mainly arising from overac-tivation of the renal Na/Cl cotransporter (NCC). In addition to full-length WNK4, we have observed faster migrating bands (between 95 and 130 kDa) in Western blots of kidney lysates. Therefore, we hypothesized that these could correspond to uncharacterized WNK4 variants. Here, using several WNK4 antibodies and WNK4/ mice as controls, we showed that these bands indeed correspond to short WNK4 variants that are not observed in other tissue lysates. LC-MS/MS confirmed these bands as WNK4 variants that lack C-terminal segments. In HEK293 cells, truncation of WNK4’s C terminus at several positions increased its kinase activity toward Ste20-related proline/ alanine-rich kinase (SPAK), unless the truncated segment included the SPAK-binding site. Of note, this gain-of-function effect was due to the loss of a protein phosphatase 1 (PP1)-bind-ing site in WNK4. Cotransfection with PP1 resulted in WNK4 dephosphorylation, an activity that was abrogated in the PP1-binding site WNK4 mutant. The electrophoretic mobility of the in vivo short variants of renal WNK4 suggested that they lack the SPAK-binding site and thus may not behave as constitutively active kinases toward SPAK. Finally, we show that at least one of the WNK4 short variants may be produced by proteolysis involving a Zn2-dependent metalloprotease, as recombinant full-length WNK4 was cleaved when incubated with kidney lysate. © 2018 American Society for Biochemistry and Molecular Biology Inc. All rights reserved.

View