C-Terminal Serine Rich Region of IKK-beta Interacts with Bfl-1, a Homologue of Bcl-2.
- Author:
Hyun Kyung YOON
1
;
Jin Koo KIM
;
Hee Jun CHO
;
Mi Young CHO
;
Yuk Pheel PARK
;
Kwan Hee YOU
;
Jong Wan KIM
;
Do Young YOON
;
Yong Kyung CHOE
;
Hee Gu LEE
Author Information
1. Laboratory of Cell Biology, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Korea. hglee@kribb.re.kr
- Publication Type:Original Article
- Keywords:
Bfl-1;
IKK-beta yeast two hybrid;
BH domain
- MeSH:
Amino Acids;
Apoptosis;
Cell Line;
Glutathione Transferase;
Humans;
I-kappa B Kinase;
NF-kappa B;
Serine*;
Two-Hybrid System Techniques
- From:The Korean Journal of Laboratory Medicine
2005;25(3):192-198
- CountryRepublic of Korea
- Language:English
-
Abstract:
BACKGROUND: Bcl-2 family proteins play a central role in regulating apoptosis. In human, over 20 members of this family have been identified to date. Bfl-1, a member of the Bcl-2 family, has been known to retard apoptosis in various cell lines. However, the function of Bfl-1 remains unclear. METHODS: In order to investigate the Bfl-1 function, we employed yeast two-hybrid system to identify the proteins which are capable of interacting with Bfl-1. The interaction of inhibitor kappaB kinase-beta (IKK-beta) and Bfl-1 was confirmed using glutathione S-transferase pull down assays. To determine which regions of IKK-beta were required for interaction with Bfl-1, we constructed 12 deletion mutants of IKK-beta and 5 deletion mutants of Bfl-1. RESULTS: Bfl-1 interacted with the C-terminal region of IKK-beta which is a subunit of IKK complex, and IKK-beta activity is very important in the NF-kappaB related pathway. In addition, the amino acids 673-745 of IKK-beta were important for Bfl-1 interactions, and amino acids 1-484 of Bfl-1, including Bcl-2 homology domains (BH1, BH2, BH3, BH4), were crucial for IKK-beta interactions. CONCLUSIONS: IKK beta C-terminus contains many serine residues as binding partner of Bfl-1. Our results suggested that Bfl-1 is involved in the NF-kappaB activation through interaction of IKK-beta and Bfl-1. Further studies need to be performed to understand functions of the IKK-beta and Bfl-1 associated with the regulation of the NF-kappaB activation pathway.
