HSP-25 and HSP-90 stabilize Na,K-ATPase in cytoskeletal fractions of ischemic rat renal cortex

32Citations
Citations of this article
17Readers
Mendeley users who have this article in their library.

Abstract

Background. We recently designed an in vitro system based on differential Triton-extractability of Na,K-ATPase from the cytoskeletal protein fraction isolated from rat renal cortex after renal ischemia. In the present study, we hypothesized that heat shock protein (HSP)-70, HSP-25 and HSP-90 work synergistically to stabilize the cytoskeletal anchorage of Na,K-ATPase. Methods. Cellular proteins were fractionated by differential centrifugation into cytoskeletal pellets (I-PEL) obtained early (exhibiting abnormally high Triton extractability of Na,K-ATPase) and non-cytoskeletal supernatants (R-SUP) obtained late (exhibiting high abundance of HSP) after renal ischemia. For assessment of the role of HSP-70, HSP-25 and HSP-90 upon in vitro re-compartmentalization, I-PEL was either incubated in R-SUP with/without HSP antibodies, or in buffer with/without HSPs at different titers and combinations. Effects were evaluated by changes of Triton extractability of Na,K-ATPase after co-incubation. Results. R-SUP was shown to contain significant amounts of HSP-70, HSP-25 and HSP-90. Incubation of I-PEL in R-SUP reduced Triton extractability of Na,K-ATPase. Addition of antibodies against each HSP significantly abolished these effects of R-SUP. Incubation of I-PEL with purified HSP-70, HSP-25 or HSP-90 each partly reproduced the effects of R-SUP, whereas the combination of all three HSP demonstrated a strong and more than additive effect on the cytoskeletal stabilization of Na,K-ATPase. Conclusions. The molecular mechanisms responsible for postischemic re-compartmentalization of Na,K-ATPase in rat renal cortex likely involves interactions between HSP-70, HSP-25 and HSP-90, stress proteins known to be induced in the ischemic kidney.

Cite

CITATION STYLE

APA

Bidmon, B., Endemann, M., Müller, T., Arbeiter, K., Herkner, K., & Aufricht, C. (2002). HSP-25 and HSP-90 stabilize Na,K-ATPase in cytoskeletal fractions of ischemic rat renal cortex. Kidney International, 62(5), 1620–1627. https://doi.org/10.1046/j.1523-1755.2002.00617.x

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free