TY - JOUR
T1 - Cloning and in vitro expression of TPK3, a Toxoplasma gondii homologue of shaggy/glycogen synthase kinase-3 kinases
AU - Qin, Chang Le
AU - Tang, Jianzhong
AU - Kim, Kami
N1 - Funding Information:
We thank Louis Weiss and Tom McDonald for review of the manuscript and James Woodgett for antibodies. This work was supported by a grant from the NIH AI 41058 (KK).
PY - 1998/6/1
Y1 - 1998/6/1
N2 - As an initial effort to dissect the signaling pathways responsible for pathogenesis of Toxoplasma gondii infection, we report the cloning and in vitro functional studies of TPK3 (Toxoplasma protein kinase-3), a homologue of shaggy/glycogen synthase kinase-3 (GSK-3) kinases. The shaggy/GSK-3 family of kinases are highly conserved protein kinases that play important roles in cell fate determination, nuclear signaling and hormonal regulation. The TPK3 gene was isolated by RT-PCR with degenerate primers corresponding to highly conserved regions of serine/threonine protein kinases. The complete sequences of genomic and cDNA clones indicated the open reading frame, 1185 bp in size, is interrupted by five introns. The predicted protein sequence of TPK3 shows 54% identity to shaggy/GSK-3 over the catalytic domains. Southern analysis revealed TPK3 is a single copy locus in the Toxoplasma genome. Antisera to other GSK-3 proteins from other species recognized GST-TPK3 and a protein of the predicted size in parasites lysates. In vitro kinase assays with GST-TPK3 indicated that TPK3 autophosphorylates and phosphorylates protein phosphatase inhibitor-2 (I-2), a specific substrate of GSK-3 kinase. Copyright (C) 1998 Elsevier Science B.V.
AB - As an initial effort to dissect the signaling pathways responsible for pathogenesis of Toxoplasma gondii infection, we report the cloning and in vitro functional studies of TPK3 (Toxoplasma protein kinase-3), a homologue of shaggy/glycogen synthase kinase-3 (GSK-3) kinases. The shaggy/GSK-3 family of kinases are highly conserved protein kinases that play important roles in cell fate determination, nuclear signaling and hormonal regulation. The TPK3 gene was isolated by RT-PCR with degenerate primers corresponding to highly conserved regions of serine/threonine protein kinases. The complete sequences of genomic and cDNA clones indicated the open reading frame, 1185 bp in size, is interrupted by five introns. The predicted protein sequence of TPK3 shows 54% identity to shaggy/GSK-3 over the catalytic domains. Southern analysis revealed TPK3 is a single copy locus in the Toxoplasma genome. Antisera to other GSK-3 proteins from other species recognized GST-TPK3 and a protein of the predicted size in parasites lysates. In vitro kinase assays with GST-TPK3 indicated that TPK3 autophosphorylates and phosphorylates protein phosphatase inhibitor-2 (I-2), a specific substrate of GSK-3 kinase. Copyright (C) 1998 Elsevier Science B.V.
KW - Glycogen synthase kinase-3
KW - Serine/threonine protein kinase
KW - Toxoplasma gondii
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U2 - 10.1016/S0166-6851(98)00042-5
DO - 10.1016/S0166-6851(98)00042-5
M3 - Article
C2 - 9662711
AN - SCOPUS:0032101958
SN - 0166-6851
VL - 93
SP - 273
EP - 283
JO - Molecular and Biochemical Parasitology
JF - Molecular and Biochemical Parasitology
IS - 2
ER -