Interaction of the PDZ domain of human PICK1 with class I ADP-ribosylation factors.

Department of Molecular Biology, Kyushu University Graduate School of Medical Science, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
Biochemical and Biophysical Research Communications (Impact Factor: 2.28). 02/2000; 267(1):149-55. DOI: 10.1006/bbrc.1999.1932
Source: PubMed

ABSTRACT We have cloned the cDNA encoding human PICK1 (protein interacting with C kinase 1), a PDZ domain-containing protein of 415 amino acids, and also identified the Drosophila homologue by search of the databank. Northern blot analysis shows a single mRNA of about 2.0 kb ubiquitously expressed in human tissues. Although PICK1 proteins harbor a region homologous to arfaptin1 and arfaptin2, two proteins that bind to the ARF (ADP-ribosylation factor), this region of PICK1 does not interact with ARFs in the yeast two-hybrid system. On the other hand, the PDZ domain of PICK1 is capable of interacting with constitutively active, GTP-bound forms of ARF1 and ARF3, but neither with those of ARF5/6 nor with the GDP-bound ARFs. The PICK1-ARF interaction is abrogated by introduction of mutations in the PDZ domain or by deletion of the extreme C-terminus of ARF1. Thus, PICK1 specifically interacts with ARF1/3 in the GTP-bound state, suggesting that PICK1 participates in ARF1/3-mediated cellular processes.

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