Title: Tight interplay between the Ca2+ affinity of the cardiac SERCA2 Ca2+ pump and the SERCA2 expression level
Authors: Vangheluwe, Peter ×
Schuermans, Marleen
Raeymaekers, Luc
Wuytack, Frank #
Issue Date: Sep-2007
Publisher: Elsevier
Series Title: Cell Calcium vol:42 issue:3 pages:281-289
Abstract: A reduced activity of the sarcoplasmic reticulum Ca2+ pump SERCA2a is a hallmark of cardiac dysfunction in heart failure. In SERCA2(b/b) mice, the normal SERCA2a isoform is replaced by SERCA2b, displaying a higher Ca2+ affinity. This elicited decreased cardiac SERCA2 expression and cardiac hypertrophy. Here, the interplay was studied between the increased Ca2+ affinity and a reduced expression of the pump and its role in the cardiac remodeling was investigated. First, SERCA2 bib mice were crossed with SERCA2b transgenes to boost cardiac SERCA2b expression. However, the enforced expression of SERCA2b was spontaneously countered by an increased inhibition by phospholamban (PLB), reducing the pump's Ca2+ affinity. Moreover, the higher SERCA2 content did not prevent hypertrophy. Second, we studied heterozygous SERCA2 b1l mice, which also express lower SERCA2 levels compared to wild-type. Hypertrophy was not observed. In heterozygotes, SERCA2b expression was specifically suppressed, explaining the reduced SERCA2 content. The SERCA2(b/WT) model strikingly differs from the homozygote models because SERCA2a (not SERCA2b) is the major isoform and because the inhibition of the pump by PLB is decreased instead of being increased. Thus, a tight correlation exists between the SERCA2 levels and Ca2+ affinity (controlled by PLB). This compensatory response may be important to prevent cardiac remodeling. (c) 2007 Elsevier Ltd. All rights reserved.
ISSN: 0143-4160
Publication status: published
KU Leuven publication type: IT
Appears in Collections:Laboratory of Cellular Transport Systems
× corresponding author
# (joint) last author

Files in This Item:

There are no files associated with this item.

Request a copy


All items in Lirias are protected by copyright, with all rights reserved.

© Web of science