Bcl-2 Family
Proteins and Apoptosis
FU Yong-Feng, FAN Ting-Jun*
( Department of Marine Biology, College of Marine Life Sciences, Ocean
University of Qingdao, Qingdao 266003, China )
Abstract Bcl-2
family proteins play key roles in apoptosis. They coordinate with other
apoptotic proteins in apoptosis to control mitochondria stability both in
structure and function, while mitochondria probably act as the main switch of
apoptosis. Bcl-2 family proteins can be divided into two types, antiapoptotic
proteins and pro-apoptotic proteins. During apoptosis, Bcl-2 family
proapoptotic proteins can translocate to the outer membrane of mitochondrion
after posttranslational modification by certain proteases such as caspases.
Then cytochrome c (cyt.c), apoptosis-inducing factors (AIFs), and
other proapoptotic factors are released from mitochondrion, triggering
apoptosis. Bcl-2 family antiapoptotic proteins sequestered in mitochondrion
have ability to inhibit the release of cyt.c and AIFs, and prevent
apoptosis. When interacting with activated proapoptotic proteins, the
antiapoptotic proteins lose inhibiting ability of pro-apoptotic factors'
release, and again triggering apoptosis. Based on the newest research
evolvements, types, structures, localizations, apoptosis regulating mechanisms
of Bcl-2 family proteins are reviewed.
Key words Bcl-2 family; apoptosis; anti-apoptotic
protein; pro-apoptotic protein
*Corresponding author: Tel,
86-532-2032276; Fax, 86-532-2032276; e-mail,
[email protected]