Studies on interactions of Sarco/Endoplasmic Reticulum Ca2+-ATPase (SERCA) with anti apoptotic protein Bcl-2.

View/ Open
Issue Date
2008-07-29Author
Hewawasam, Geetha S.
Publisher
University of Kansas
Format
169 pages
Type
Dissertation
Degree Level
PH.D.
Discipline
Chemistry
Rights
This item is protected by copyright and unless otherwise specified the copyright of this thesis/dissertation is held by the author.
Metadata
Show full item recordAbstract
Bcl-2 regulates apoptosis by controlling luminal Ca2+ concentration of endoplasmic reticulum (ER). Dremina et al. reported that Bcl-2 interacts with SERCA, the Ca2+ pump in SR/ER membrane, causing inactivation and translocation. This work reports the characteristics of the SERCA/Bcl-2 interactions using wild type and three mutants, G145E, S24C/C158S and S205C/C158S, of the truncated protein, Bcl-2Δ21. Protein cross-linking, Ca2+-ATPase activity assay, Sucrose Density Gradient fractionation, immunoprecipitation and the fusion protein binding assay are the approaches used. Results reveal that the two proteins can interact with both 1:1 and 2:1 (Bcl-2Δ21: SERCA) molar ratios. The hydrophobic groove of Bcl-2Δ21 is involved in the interactions. The BH1 domain of Bcl-2Δ21 interacts with the ATP binding domain of SERCA. The G145E mutant is a loss-of-function whereas the two Cys-mutants are gain-of-function on SERCA inactivation and translocation. Therefore the conserved residue G145 is a critical hot spot for the Bcl-2Δ21-mediated inactivation and translocation of SERCA.
Collections
- Chemistry Dissertations and Theses [335]
- Dissertations [4660]
Items in KU ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.
We want to hear from you! Please share your stories about how Open Access to this item benefits YOU.