Document Detail
Calcium signaling in apoptotic mammalian cells
Abstract/OtherAbstract :
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2008, xx, 169 leaves : ill. (some col.) ; 30 cm, HKUST Call Number: Thesis BIOL 2008 Lao, The calcium ion (Ca2+), as an important second messenger, is known to be involved in many cellular functions. The present study is aimed at investigating the roles of Ca2+ signaling in regulating apoptosis of mammalian cells. We tried to answer the following questions: (1) Is the mitochondrial Ca2+ signal involved in the early stage to drive the progression of apoptosis? (2) What are the characteristics and transportation mechanisms of the mitochondrial Ca2+ signal in apoptosis? (3) What are the mechanisms by which the Bcl-2 family proteins such as Bcl-2 and Bax regulate the Ca2+ mobilization from endoplasmic reticulum (ER) to cytosol and mitochondria during apoptosis? (4) Are there any other regulators such as Bcl-2 family proteins binding partners affecting the Ca2+ signals? Using single living cell Ca2+ imaging techniques, we found that mitochondrial Ca2+ signal plays a positive role in the early stage of UV- or TNFα- induced apoptosis in HeLa cells. The transient mitochondrial Ca2+ spikes are synchronous with the cytosolic Ca2+ changes. Our results suggested that the Ca2+ release from ER plays an important role on regulating the apoptotic process since the cytosolic Ca2+ elevation during ATP treatment and TNFα-induced apoptosis are highly correlated. We then investigated the mechanisms by which Bcl-2 family proteins affect the IP3 dependent Ca2+ mobilization. We found that pro-apoptotic protein Bax can counteract with anti-apoptotic Bcl-2 to facilitate the ER Ca2+ release by interacting with IP3 receptor. Our results suggested that Bax could sensitize the IP3 receptor, while Bcl-2 could inhibit IP3 receptor during apoptosis. Finally, we examined the effect of other Bcl-2 family proteins and their binding partners on Ca2+ signaling. Our results indicated that the Bcl-2 family proteins may regulate the apoptotic process through modulating the Ca2+ mobilization from ER to cytosol and mitochondria.
Authors :
Lao, Yuanzhi
Related Documents :
36657724 - Calcium signaling in apoptotic mammalian cells
8202864 - Lsd1 complex controls cell type terminal differentiation during mammalian organogenesis
6619514 - Digital implementation of a stellate cell using the macgregor cell model
1110024 - High dilutions of euphorbia tirucalli l. (aveloz) modify the viability and glycolytic m...
Contributors :
Publication Detail :
Publisher :  -     Type :  Thesis     Format :  339 bytes, text/html    
Date Detail :
2009-02-16, 2009-02-16, 2008
Subject :
Apoptosis, Calcium channels, Cellular signal transduction
Coverage :
Relation :
Source :
Copyright Information :
Other Details :
Languages :  en_US    
Export Citation :
APA/MLA Format     Download EndNote     Download BibTex

Previous Document:  The Hydrology and Biology of Cypress Creek (Hays County), a Subtropical Karstic Stream in South Cent...
Next Document:  MAB-30 functions to maintain cell identity of sensory ray in C. elegans