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Renal COP9 signalosome deficiency alters CUL3-KLHL3-WNK signaling pathway
- Publication Year :
- 2018
- Publisher :
- American Society of Nephrology, 2018.
-
Abstract
- Background The familial hyperkalemic hypertension (FHHt) cullin 3 (CUL3) mutant does not degrade WNK kinases normally, thereby leading to thiazide-sensitive Na-Cl cotransporter (NCC) activation. CUL3 mutant (CUL3 Δ 9) does not bind normally to the COP9 signalosome (CSN), a deneddylase involved in regulating cullin-RING ligases. CUL3 Δ 9 also caused increased degradation of the CUL3-WNK substrate adaptor kelch-like 3 (KLHL3). Here, we sought to determine how defective CSN action contributes to the CUL3 Δ 9 phenotype. Methods The Pax8/LC1 mouse system was used to generate mice in which the catalytically active CSN subunit, Jab1 , was deleted only along the nephron, after full development (KS- Jab1 −/− ). Results Western blot analysis demonstrated that Jab1 deletion increased the abundance of neddylated CUL3. Moreover, total CUL3 expression was reduced, suggesting decreased CUL3 stability. KLHL3 was almost completely absent in KS- Jab1 −/− mice. Conversely, the protein abundances of WNK1, WNK4, and SPAK kinases were substantially higher. Activation of WNK4, SPAK, and OSR1 was indicated by higher phosphorylated protein levels and translocation of the proteins into puncta, as observed by immunofluorescence. The ratio of phosphorylated NCC to total NCC was also higher. Surprisingly, NCC protein abundance was low, likely contributing to hypokalemia and Na + and K + wasting. Additionally, long-term Jab1 deletion resulted in kidney damage. Conclusions Together, the results indicate that deficient CSN binding contributes importantly to the FHHt phenotype. Although defective CUL3 Δ 9-faciliated WNK4 degradation likely contributes, dominant effects on KLHL3 may be a second factor that is necessary for the phenotype.
- Subjects :
- 0301 basic medicine
Male
Transport Physiology
Pseudohypoaldosteronism
Protein-Serine-Threonine Kinase
Kidney
Mice
0302 clinical medicine
HEK293 Cell
Nephron
Proteolysi
Mice, Knockout
biology
Chemistry
Kinase
Microfilament Proteins
Cell &
Intracellular Signaling Peptides and Proteins
General Medicine
WNK1
Cullin Proteins
Na transport
Cell biology
WNK4
Phenotype
Nephrology
030220 oncology & carcinogenesis
Phosphorylation
Female
Signal transduction
Cullin
Human
Signal Transduction
distal tubule
Protein subunit
Protein Serine-Threonine Kinases
03 medical and health sciences
Animals
Humans
renal hypertension
COP9 signalosome
Adaptor Proteins, Signal Transducing
urogenital system
Animal
COP9 Signalosome Complex
Cullin Protein
Nephrons
Microfilament Protein
Mice, Inbred C57BL
Disease Models, Animal
030104 developmental biology
Basic Research
HEK293 Cells
Peptide Hydrolase
Microscopy, Fluorescence
Intracellular Signaling Peptides and Protein
Proteolysis
Mutation
biology.protein
Peptide Hydrolases
Subjects
Details
- Language :
- English
- Database :
- OpenAIRE
- Accession number :
- edsair.doi.dedup.....4ddba382ec11769690c55f79c485752d