The Sarco-Endoplasmic Reticulum Ca2+ ATPase (SERCA) is the operator of active Ca2+ transport into intracellular stores. The stored Ca2+ is in turn released to trigger cytosolic Ca2""""""""1"""""""" signaling. In cardiac and skeletal muscle Ca2+ transport and Ca2+ signaling play prominent roles in control of relaxation and contraction, as well as other functions such as transcriptional activation. These functions are altered in cardiac failure.
The aims of this project are: (1) clarification of the molecular mechanism whereby ATP is utilized to move Ca2+ against a concentration gradient; (2) establishment of strategies for gene transfer into cardiac myocytes, and definition of the consequences of overexpression or silencing SERCA and other genes encoding Ca2+ signaling proteins. The research related to aim (1) will produce specific modifications in native and recombinant ATPase by protein chemistry and site directed mutagenesis, and will define the effects of these modifications on the sequential ATPase reactions that are coupled to Ca2+ transport. The findings will be related to crystallographic data and diffraction analysis, to indicate how various ATPase protein domains and specific amino acid residues are involved in energy transduction. Binding sites and specific effects of inhibitors will be defined. It is expected that the mechanism of this enzyme, as a prototype of active transport and energy transduction, will be solved at the molecular and atomic level. The research related to aim (2) will be mostly based on exogenous cDNA delivery to cardiac myocytes by means of recombinant adenovirus vectors under control of specific promoters, thereby optimizing gene transfer and silencing strategies for basic studies of cardiac cell physiology in culture. The functional consequences of SERCA up- or downregulation on Ca2+ signaling, contraction/relaxation cycle and cellular homeostasis will be defined. In addition the effects of silencing specifically SERCA or other genes (i.e., calcineurin) on transcription and expression of other proteins and remodeling of the Ca2+ signaling pathways will be studied. This work will allow us to explore and clarify a new and important concept indicating that in addition to short term functional modulation (i.e., adrenergic), long term changes in copy number, diversity and profile of Ca2+ signaling proteins are important factors in cardiac remodeling, hypertrophy, failure, and possible treatment. ? ? ?

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
2R01HL069830-05
Application #
7073010
Study Section
Biochemistry and Biophysics of Membranes Study Section (BBM)
Program Officer
Przywara, Dennis
Project Start
2002-09-01
Project End
2011-08-31
Budget Start
2006-09-01
Budget End
2007-08-31
Support Year
5
Fiscal Year
2006
Total Cost
$583,468
Indirect Cost
Name
California Pacific Medical Center Research Institute
Department
Type
DUNS #
071882724
City
San Francisco
State
CA
Country
United States
Zip Code
94107
Tadini-Buoninsegni, Francesco; Bartolommei, Gianluca; Moncelli, Maria Rosa et al. (2014) Translocation of platinum anticancer drugs by human copper ATPases ATP7A and ATP7B. Angew Chem Int Ed Engl 53:1297-301
Lewis, David; Pilankatta, Rajendra; Inesi, Giuseppe et al. (2012) Distinctive features of catalytic and transport mechanisms in mammalian sarco-endoplasmic reticulum Ca2+ ATPase (SERCA) and Cu+ (ATP7A/B) ATPases. J Biol Chem 287:32717-27
Tadini-Buoninsegni, Francesco; Bartolommei, Gianluca; Moncelli, Maria Rosa et al. (2010) ATP dependent charge movement in ATP7B Cu+-ATPase is demonstrated by pre-steady state electrical measurements. FEBS Lett 584:4619-22
Prasad, A M; Inesi, G (2010) Downregulation of Ca2+ signalling proteins in cardiac hypertrophy. Minerva Cardioangiol 58:193-204
Liu, Yueyong; Pilankatta, Rajendra; Lewis, David et al. (2009) High-yield heterologous expression of wild type and mutant Ca(2+) ATPase: Characterization of Ca(2+) binding sites by charge transfer. J Mol Biol 391:858-71
Pilankatta, Rajendra; Lewis, David; Adams, Christopher M et al. (2009) High yield heterologous expression of wild-type and mutant Cu+-ATPase (ATP7B, Wilson disease protein) for functional characterization of catalytic activity and serine residues undergoing copper-dependent phosphorylation. J Biol Chem 284:21307-16
Prasad, Anand Mohan; Inesi, Giuseppe (2009) Effects of thapsigargin and phenylephrine on calcineurin and protein kinase C signaling functions in cardiac myocytes. Am J Physiol Cell Physiol 296:C992-C1002
Hatori, Yuta; Lewis, David; Toyoshima, Chikashi et al. (2009) Reaction cycle of Thermotoga maritima copper ATPase and conformational characterization of catalytically deficient mutants. Biochemistry 48:4871-80
Zafar, Sufi; Hussain, Arif; Liu, Yueyong et al. (2008) Specificity of ligand binding to transport sites: Ca2+ binding to the Ca2+ transport ATPase and its dependence on H+ and Mg2+. Arch Biochem Biophys 476:87-94
Inesi, Giuseppe; Nakamoto, Robert K (2008) Special issue on transport ATPases. Arch Biochem Biophys 476:1-2

Showing the most recent 10 out of 22 publications