Identification of a novel 300‐kDa factor termed IκBαE3‐F1 that is required for ubiquitinylation of IκBα

FEBS Letters

Furuichi, Kiyoshi¹  Chiba, Tomoki²  Kobayashi, Masato¹  Takeuchi, Masahiro¹  Tanaka, Keiji²  Suzuki, Hiroshi¹ 

[1] Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co., Ltd., 21 Miyukigaoka, Tsukuba-shi, Ibaraki 305-8585, Japan;The Tokyo Metropolitan Institute of Medical Science, and CREST, Japan Science and Technology Corporation (JST), 3-18-22 Honkomagome, Bunkyo-ku, Tokyo 113-8613, Japan

关键词: Ubiquitin;    SCF;    IκB;    NF-κB;    Tumor necrosis factor α;   

DOI  :  10.1016/S0014-5793(99)01173-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Destruction of IκB by ubiquitinylation is required for signal-dependent activation of NF-κB. The IκBα ubiquitin-ligase activity associated with phosphorylated IκBα (pIκBα) in HeLa cells was almost completely lost by washing under stringent conditions including 1 M NaCl; nevertheless, an SCF^βTrCP complex containing Skp1, Cullin-1, and F-box/WD40 protein βTrCP was still bound to pIκBα, suggesting the existence of a putative factor that is loosely associated with pIκBα and may collaborate with SCF^βTrCP. The factor was named IκBαE3-F1 and was partially purified from HeLa cells. Gel filtration analysis revealed that IκBαE3-F1 has an apparent molecular mass of approximately 300 kDa.

【 授权许可】

Unknown