TY - JOUR
T1 - Primary structures of two homologous subunits of PA28, a γ-interferon-inducible protein activator of the 20S proteasome
AU - Joon Young Ahn, Young Ahn
AU - Nobuyuki Tanahashi, Tanahashi
AU - Kin-ya Akiyama, Akiyama
AU - Hiroshi Hisamatsu, Hisamatsu
AU - Chiseko Noda, Noda
AU - Keiji Tanaka, Tanaka
AU - Chin Ha Chung, Ha Chung
AU - Naoki Shibmara, Shibmara
AU - Willy, Patricia J.
AU - Mott, Joni D.
AU - Slaughter, Clive A.
AU - DeMartino, George N.
PY - 1995/6/5
Y1 - 1995/6/5
N2 - The primary structures of two proteins that comprise PA28, an activator of the 20S proteasome, have been determined by cDNA cloning and sequencing. These protein subunits, termed PA28α and PA28β, are about 50% identical to one another and are highly conserved between rat and human. PA28α and PA28β are homologous to a previously described protein, Ki antigen, whose function is unknown. PA28α, but neither PA28β nor Ki antigen, contains a 'KEKE motif', which has been postulated to promote the binding of proteins having this structural feature. PA28α and PA28β were coordinately regulated by γ-interferon, which greatly induced mRNA levels of both proteins in cultured cells. The mRNA level of the Ki antigen also increased in response to γ-interferon treatment, but the magnitude of the increase was less than that for the PA28s, and the effect was transient. These results demonstrate the existence of a new protein family, at least two of whose members are involved in proteasome activation. They also provide the basis for future structure/function studies of PA28 subunits and the determination of their relative physiological roles in the regulation of proteasome activity.
AB - The primary structures of two proteins that comprise PA28, an activator of the 20S proteasome, have been determined by cDNA cloning and sequencing. These protein subunits, termed PA28α and PA28β, are about 50% identical to one another and are highly conserved between rat and human. PA28α and PA28β are homologous to a previously described protein, Ki antigen, whose function is unknown. PA28α, but neither PA28β nor Ki antigen, contains a 'KEKE motif', which has been postulated to promote the binding of proteins having this structural feature. PA28α and PA28β were coordinately regulated by γ-interferon, which greatly induced mRNA levels of both proteins in cultured cells. The mRNA level of the Ki antigen also increased in response to γ-interferon treatment, but the magnitude of the increase was less than that for the PA28s, and the effect was transient. These results demonstrate the existence of a new protein family, at least two of whose members are involved in proteasome activation. They also provide the basis for future structure/function studies of PA28 subunits and the determination of their relative physiological roles in the regulation of proteasome activity.
KW - Ki antigen
KW - Multicatalytic proteinase complex
KW - Proteasome
KW - Proteasome activator PA28
KW - cDNA cloning
KW - γ-Interferon
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U2 - 10.1016/0014-5793(95)00492-R
DO - 10.1016/0014-5793(95)00492-R
M3 - Article
C2 - 7789512
AN - SCOPUS:0029000418
SN - 0014-5793
VL - 366
SP - 37
EP - 42
JO - FEBS Letters
JF - FEBS Letters
IS - 1
ER -