TY - JOUR
T1 - cDNA cloning and functional analysis of p28 (Nas6p) and p40.5 (Nas7p), two novel regulatory subunits of the 26S proteasome
AU - Hori, Tomoko
AU - Kato, Seishi
AU - Saeki, Mihoro
AU - DeMartino, George N.
AU - Slaughter, Clive A.
AU - Takeuchi, Junko
AU - Toh-e, Akio
AU - Tanaka, Keiji
N1 - Funding Information:
This work was supported in part by grants from the program Grants-in-aid for Scientific Research on Priority Areas (Intracellular Proteolysis) from the Ministry of Education, Science, Sports, and Culture of Japan, and the Human Frontier Science Promotion Organization (K.T. and G.N.D.).
PY - 1998/8/17
Y1 - 1998/8/17
N2 - We employed cDNA cloning to deduce the complete primary structures of p28 and p40.5, two novel subunits of PA700 (also called 19S complex), a 700 kDa multisubunit regulatory complex of the human 26S proteasome. These polypeptides consisted of 226 and 376 amino acids with calculated molecular masses of 24,428 Da and 42,945 Da, and isoelectric points of 5.68 and 5.46, respectively. Intriguingly, p28 contained five conserved motifs known as 'ankyrin repeats', implying that this subunit may contribute to interaction of the 26S proteasome with other protein(s). Computer-assisted homology analysis revealed high sequence similarities of p28 and p40.5 with yeast proteins, termed Nas6p and Nas7p (non-ATPase subunits 6 and 7), respectively, whose functions are as yet unknown. Disruption of these yeast genes, NAS6 and NAS7, had no effect on cell viability, indicating that neither of the two subunits is essential for proliferation of yeast cells. However, the NAS7, but not NAS6, disruptant cells caused high sensitivity to heat stress, being unable to proliferate at 37°C.
AB - We employed cDNA cloning to deduce the complete primary structures of p28 and p40.5, two novel subunits of PA700 (also called 19S complex), a 700 kDa multisubunit regulatory complex of the human 26S proteasome. These polypeptides consisted of 226 and 376 amino acids with calculated molecular masses of 24,428 Da and 42,945 Da, and isoelectric points of 5.68 and 5.46, respectively. Intriguingly, p28 contained five conserved motifs known as 'ankyrin repeats', implying that this subunit may contribute to interaction of the 26S proteasome with other protein(s). Computer-assisted homology analysis revealed high sequence similarities of p28 and p40.5 with yeast proteins, termed Nas6p and Nas7p (non-ATPase subunits 6 and 7), respectively, whose functions are as yet unknown. Disruption of these yeast genes, NAS6 and NAS7, had no effect on cell viability, indicating that neither of the two subunits is essential for proliferation of yeast cells. However, the NAS7, but not NAS6, disruptant cells caused high sensitivity to heat stress, being unable to proliferate at 37°C.
KW - 26S proteasome
KW - Gene disruption
KW - Non-ATPase subunit
KW - PA700
KW - cDNA cloning
KW - p28 subunit
KW - p40.5 subunit
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U2 - 10.1016/S0378-1119(98)00309-6
DO - 10.1016/S0378-1119(98)00309-6
M3 - Article
C2 - 9714768
AN - SCOPUS:0032541323
SN - 0378-1119
VL - 216
SP - 113
EP - 122
JO - Gene
JF - Gene
IS - 1
ER -