cDNA cloning of p42, a shared subunit of two proteasome regulatory proteins, reveals a novel member of the AAA protein family

FEBS Letters

Slaughter, Clive A.³  Tanaka, Keiji¹  Fujiwara, Tsutomua⁴  Watanabe, Takeshi K.⁴  DeMartino, George N.² 

[1] Institute for Enzyme Research, The University of Tokushima, Tokushima 770, Japan;Department of Physiology, The University of Texas Southwestern Medical Center, Dallas, TX 75235, USA;The Howard Hughes Medical Institute, The University of Texas Southwestern Medical Center, Dallas, TX 75235, USA;Otsuka GEN Research Institute, Otsuka Pharmaceutical Company, Ltd., 463-10 Kagasuno, Kawauchi-cho, Tokushima 771-01, Japan

关键词: Proteasome;    PA700;    Sug2p;    AAA protein family;    ATPase;    Modulator;    p42;   

DOI  :  10.1016/0014-5793(96)00489-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We have employed cDNA cloning to deduce the complete primary structure of p42, a protein previously identified as a common subunit of two proteasome regulatory proteins: PA700, a 700 000-Da multisubunit complex that binds to the proteasome and promotes the ATP-dependent degradation of ubiquitinated proteins, and modulator, a 250 000-Da PA700-dependent proteasome activator. Computer analysis reveals that p42 is a novel member of a large protein family characterized by a conserved 200 amino acid domain which contains a consensus sequence for ATP binding. Five other members of this family, termed AAA proteins (TPases ssociated with a variety of cellular ctivities) are also subunits of PA700. Gel filtration chromatography was employed to determine the qualitative and quantitative distribution of p42 in crude soluble lysates of bovine red blood cells. These studies demonstrated that p42 was found in two multi-protein complexes: the 26S proteasome (formed from the 20S proteasome and PA700) and the modulator. These results establish the identity of a new protein involved in the regulation of proteasome function and indicate that this protein is found in at least two different protein complexes.

【 授权许可】

Unknown