Identification of Nck Family Genes, Chromosomal Localization, Expression, and Signaling Specificity

doi:10.1074/jbc.273.39.25171

Identification of Nck Family Genes, Chromosomal Localization, Expression, and Signaling Specificity*

From the ^¶Ben May Institute for Cancer Research and the Department of Pharmacological and Physiological Sciences, the ^‡Department of Biochemistry and Molecular Biology, and the ^‖Section of Hematology and Oncology, the Department of Medicine, the University of Chicago, Chicago, Illinois 60637 and the ^**Rosenstiel Basic Medical Sciences Research Center and Department of Biology, Brandeis University, Waltham, Massachusetts 02254

Abstract

Already a dozen molecules share binding to the Src homology (SH) 3 domains of human Nck, an SH3-SH3-SH3-SH2 adapter protein. We reason that there may be multiple gene members of Nck to accommodate the large binding repertoires. Here we report identification of novel human and mouse Nck genes and rename them as the Nckα and Nckβ genes (including the human Nckα, human Nckβ, mouse Nckα, and mouse Nckβ genes). Nckα and Nckβ share 68% amino acid identity, whereas the two Nckα and two Nckβ across the species show 96% identity to each other. The human Nckβ gene is mapped to 2q12, whereas the human Nckα gene has previously been mapped at 3q21. Antibodies specifically against Nckα and Nckβ detect Nckα and Nckβ with an identical molecular mass in the same cells of various origins. Ectopically expressed Nckβ, but not its SH2 domain mutant, strongly inhibits epidermal growth factor- and platelet-derived growth factor-stimulated DNA synthesis. Consistently, epidermal growth factor receptor and platelet-derived growth factor receptor preferentially interact with Nckβ over Nckα in vitro. This study indicates that Nck is a multiple gene family and that each gene may have its own signaling specificity. Because previous anti-Nck (human Nckα) antibodies cross-react with Nckβ, reassessment of those studies with specific Nck genes would be necessary.

Footnotes

↵* This work was supported in part by U.S. Public Health Service Grant CA40046 (to M. M. L.) and by NCI, National Institutes of Health, Grants CA68008 (to R. R.) and CA65567 (to W. L.).The costs of publication of this article were defrayed in part by the payment of page charges. The article must therefore be 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) AFO43119, AFO43259, and AFO43260 (for human Nckβ, mouse Nckα, and mouse Nckβ, respectively).
↵§ These authors contributed equally to this work.
↵‡ Recipient of an American Cancer Society Junior Faculty Research Award.
↵§§ To whom correspondence should be addressed: Ben May Institute for Cancer Research, Dept. of Pharmacological and Physiological Sciences, University of Chicago, 5841 South Maryland, MC6027, Chicago, IL 60637. Tel.: 773-753-1408; Fax: 773-702-6260; E-mail: wli{at}ben-may.bsd.uchicago.edu.
↵2 A. J. Wong and B. J. Mayer, GenBank^TM accession number U85781.
↵3 L. Quilliam, personal communication.
Abbreviations:

SH2 and SH3

Src homology domain 2 and 3, respectively

DOK

downstream of kinases

EGF

epidermal growth factor

EGFR

EGF receptor

PDGF

platelet-derived growth factor

PDGFR

PDGF receptor

HA

influenza virus hemagglutinin

GST

glutathione S-transferase

DAPI

4,6-diamidine-2-phenylindole.
- Received February 18, 1998.
- Revision received July 17, 1998.
The American Society for Biochemistry and Molecular Biology, Inc.