Casein kinase II interacts with prion protein in vitro and forms complex with native prion protein in vivo.
The most essential and crucial step during the pathogenesis of transmissible spongiform encephalopathy is the conformational change of cellular prion protein to pathologic isoform. Casein kinase II (CK2) is a ubiquitously expressed and evolutionarily conserved pleiotropic protein kinase that is essential for viability. To explore the possible molecular interaction between CK2 and prion protein (PrP), the full-length sequences of human CK2alpha and CK2beta complementary DNA were amplified with reverse transcription-polymerase chain reaction using the total messenger RNA from cell line SH-SY5Y as the template; then, the fusion proteins histidine-CK2alpha and glutathione S-transferase-histidine-CK2beta were expressed in Escherichia coli. The interaction between CK2 and PrP was evaluated with co-immunoprecipitation and pull-down assays. The results demonstrated that recombinant PrP bound specifically with CK2alpha, but not with CK2beta. The native CK2 and PrP in hamster brains interacted with each other, forming protein complexes. Three different glycosylated forms of PrP (diglycosylated, monoglycosylated and unglycosylated PrP) from normal brains interacted with the CK2alpha subunit, though the unglycosylated PrP seemed to have a stronger binding ability with CK2alpha subunit. The domain responsible for interacting with CK2alpha was located at the C-terminal segment of PrP (residues 91-231). This study proposed reliable experimental data for the molecular interaction between PrP and CK2alpha (both in recombinant and native categories), scientific clues for further assessing the potential biological significance of the PrP-CK2 interaction, and the possible role of CK2 in the pathogenesis of prion diseases.
Chen
Jianming
J
State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
Gao
Chen
C
Shi
Qi
Q
Wang
Guirong
G
Lei
Yanjun
Y
Shan
Bing
B
Zhang
Baoyun
B
Dong
Chenfang
C
Shi
Song
S
Wang
Xin
X
Tian
Chan
C
Han
Jun
J
Dong
Xiaoping
X
D001483:Base Sequence; D047390:Casein Kinase II / Q000378:metabolism*; D002460:Cell Line; D017931:DNA Primers; D006801:Humans; D047468:Immunoprecipitation; D011328:Prions / Q000378:metabolism*; D011485:Protein Binding; D011994:Recombinant Proteins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
D017931:DNA Primers; D011328:Prions; D011994:Recombinant Proteins; D047390:Casein Kinase II