Molecular Cloning and Sequencing of the Cytostatic G Protein-activated Protein Kinase PAK I

doi:10.1074/jbc.271.11.6206

Molecular Cloning and Sequencing of the Cytostatic G Protein-activated Protein Kinase PAK I (*)

From the Department of Biochemistry, University of California, Riverside, California 92521

^§To whom correspondence should be addressed.

Abstract

The serine/threonine protein kinase PAK I (p21-activated protein kinase), a ubiquitous multipotential protein kinase of 58-60 kDa, has been shown to have cytostatic properties. Data from our laboratory show that PAK I is highly active in oocytes and quiescent and serum-starved cells, and injection of active PAK I into one blastomere of two-cell frog embryos inhibits cleavage of the injected blastomere. To clone the cDNA encoding PAK I, purified peptides from rabbit PAK I were sequenced, degenerate oligonucleotides were used to isolate PAK I clones from a rabbit spleen library, and the 5′-terminus was obtained by polymerase chain reaction. The entire cDNA sequence extends over 4471 nucleotides, with an open reading frame for a protein of 524 residues and a 3′-noncoding region of 2826 nucleotides. Clones with the same open reading frame but with 3′-noncoding regions of 1055 and 2478 nucleotides were isolated, suggesting the generation of different transcripts by alternative termination of transcription. The amino acid sequence of PAK I shows high homology to the p21-activated protein kinases from human placenta and rat brain and to yeast STE20. PAK I is activated by Cdc42(GTP). The PAK enzymes have been proposed to regulate the stress-activated protein kinase (also known as the Jun kinase) signaling pathway (Coso, O. A., Chiariello, M., Yu, J.-C., Teramoto, H., Crespo, P., Xu, N., Miki, T., and Gutkind, J. S.(1995) Cell 81, 1137-1146; Minden, A., Lin, A., Claret, F.-X., Abo, A., and Karin, M.(1995) Cell 81, 1147-1157).

Footnotes

↵* This work was supported by United States Public Health Service Grant GM26738. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore by hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

The nucleotide sequence(s) reported in this paper has been submitted to the GenBank(™)/EMBL Data Bank with accession number(s) U46915[GenBank].
↵¹W. E. Meek, N. Grankowski, P. T. Tuazon, R. D. Rooney, and J. A. Traugh, submitted for publication.
↵²R. D. Rooney, P. T. Tuazon, and J. A. Traugh, manuscript in preparation.
↵³ The abbreviations used are:

eIF

eukaryotic initiation factor

RACE

rapid amplification of cDNA ends

GST

glutathione S-transferase

PCR

polymerase chain reaction

bp

base pair(s)

GTPS

guanosine 5′-O-(3-thiotriphosphate)

MAP

microtubule-associated protein.
- Received October 2, 1995.
- Revision received December 27, 1995.