Adenosine-binding motif mimicry and cellular effects of a thieno[2,3-d]pyrimidine-based chemical inhibitor of atypical protein kinase C isoenzymes

TY - JOUR

T1 - Adenosine-binding motif mimicry and cellular effects of a thieno[2,3-d]pyrimidine-based chemical inhibitor of atypical protein kinase C isoenzymes

AU - Kjaer, Svend

AU - Linch, Mark

AU - Purkiss, Andrew

AU - Kostelecky, Brenda

AU - Knowles, Phillip P.

AU - Rosse, Carine

AU - Riou, Philippe

AU - Soudy, Christelle

AU - Kaye, Sarah

AU - Patel, Bhavisha

AU - Soriano, Erika

AU - Murray-Rust, Judith

AU - Barton, Caroline

AU - Dillon, Christian

AU - Roffey, Jon

AU - Parker, Peter J.

AU - McDonald, Neil Q.

PY - 2013/4/15

Y1 - 2013/4/15

N2 - The aPKC [atypical PKC (protein kinase C)] isoforms iota and zeta play crucial roles in the formation and maintenance of cell polarity and represent attractive anti-oncogenic drug targets in Ras-dependent tumours. To date, few isoform-specific chemical biology tools are available to inhibit aPKC catalytic activity. In the present paper, we describe the identification and functional characterization of potent and selective thieno[2,3-d]pyrimidine-based chemical inhibitors of aPKCs. A crystal structure of human PKC iota kinase domain bound to a representative compound, CRT0066854, reveals the basis for potent and selective chemical inhibition. Furthermore, CRT0066854 displaces a crucial Asn-Phe-Asp motif that is part of the adenosine-binding pocket and engages an acidic patch used by arginine-rich PKC substrates. We show that CRT0066854 inhibits the LLGL2 (lethal giant larvae 2) phosphorylation in cell lines and exhibits phenotypic effects in a range of cell-based assays. We conclude that this compound can be used as a chemical tool to modulate aPKC activity in vitro and in vivo and may guide the search for further aPKC-selective inhibitors.

AB - The aPKC [atypical PKC (protein kinase C)] isoforms iota and zeta play crucial roles in the formation and maintenance of cell polarity and represent attractive anti-oncogenic drug targets in Ras-dependent tumours. To date, few isoform-specific chemical biology tools are available to inhibit aPKC catalytic activity. In the present paper, we describe the identification and functional characterization of potent and selective thieno[2,3-d]pyrimidine-based chemical inhibitors of aPKCs. A crystal structure of human PKC iota kinase domain bound to a representative compound, CRT0066854, reveals the basis for potent and selective chemical inhibition. Furthermore, CRT0066854 displaces a crucial Asn-Phe-Asp motif that is part of the adenosine-binding pocket and engages an acidic patch used by arginine-rich PKC substrates. We show that CRT0066854 inhibits the LLGL2 (lethal giant larvae 2) phosphorylation in cell lines and exhibits phenotypic effects in a range of cell-based assays. We conclude that this compound can be used as a chemical tool to modulate aPKC activity in vitro and in vivo and may guide the search for further aPKC-selective inhibitors.

KW - GLIOBLASTOMA CELLS

KW - ATP pocket

KW - LAMBDA/IOTA

KW - POLARITY

KW - cell migration

KW - Madin-Darby canine kidney (MDCK) cell

KW - protein kinase A/protein kinase G/protein kinase C family kinase (AGC kinase)

KW - APKC

KW - ZETA

KW - TRANSFORMED GROWTH

KW - ACTIVATION

KW - atypical protein kinase C

KW - chemical inhibitor

KW - BREAST-CANCER

KW - cell polarity

KW - cell-based assay

KW - crystallography

KW - CANCER-CELLS

KW - PKC-IOTA

U2 - 10.1042/BJ20121871

DO - 10.1042/BJ20121871

M3 - Article

SN - 0264-6021

VL - 451

SP - 329

EP - 342

JO - Biochemical Journal

JF - Biochemical Journal

IS - 2

ER -