This Article Full Text Full Text (PDF) All Versions of this Article: 133/3/1360    most recent pp.103.029272v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via ISI Web of Science (12) Citing Articles via Google Scholar Google Scholar Articles by Stary, S. Articles by Bachmair, A. Search for Related Content PubMed PubMed Citation Articles by Stary, S. Articles by Bachmair, A. Agricola Articles by Stary, S. Articles by Bachmair, A.

BIOCHEMICAL PROCESSES AND MACROMOLECULAR STRUCTURES

PRT1 of Arabidopsis Is a Ubiquitin Protein Ligase of the Plant N-End Rule Pathway with Specificity for Aromatic Amino-Terminal Residues¹

Institute of Botany, University of Vienna, Rennweg 14, A–1030 Vienna, Austria (S.S., T.P., P.S., V.N., A.B.); and Max Planck Institute for Plant Breeding Research, Department of Plant Developmental Biology, D–50829 Cologne, Germany (X.-j.Y., A.B.)

The gene PRT1 of Arabidopsis, encoding a 45-kD protein with two RING finger domains, is essential for the degradation of F-dihydrofolate reductase, a model substrate of the N-end rule pathway of protein degradation. We have determined the function of PRT1 by expression in yeast (Saccharomyces cerevisiae). PRT1 can act as a ubiquitin protein ligase in the heterologous host. The identified substrates of PRT1 have an aromatic residue at their amino-terminus, indicating that PRT1 mediates degradation of N-end rule substrates with aromatic termini but not of those with aliphatic or basic amino-termini. Expression of model substrates in mutant and wild-type plants confirmed this substrate specificity. A ligase activity exclusively devoted to aromatic amino-termini of the N-end rule pathway is apparently unique to plants. The results presented also imply that other known substrates of the plant N-end rule pathway are ubiquitylated by one or more different ubiquitin protein ligases.

¹ This work was supported by the Austrian Science Foundation FWF (grant no. P 13927) and by the Max Planck Society.

² Present address: Institut de Biologie Moléculaire des Plantes, 12 rue du Général Zimmer, 67084 Strasbourg cedex, France.

^* Corresponding author; e-mail bachmair{at}mpiz-koeln.mpg.de; fax 49–221–5062–207.

Received June 29, 2003; returned for revision July 16, 2003; accepted July 21, 2003.

This article has been cited by other articles:

				Z. Xia, A. Webster, F. Du, K. Piatkov, M. Ghislain, and A. Varshavsky Substrate-binding Sites of UBR1, the Ubiquitin Ligase of the N-end Rule Pathway J. Biol. Chem., August 29, 2008; 283(35): 24011 - 24028. [Abstract] [Full Text] [PDF]

				T. Tasaki, L. C. F. Mulder, A. Iwamatsu, M. J. Lee, I. V. Davydov, A. Varshavsky, M. Muesing, and Y. T. Kwon A Family of Mammalian E3 Ubiquitin Ligases That Contain the UBR Box Motif and Recognize N-Degrons Mol. Cell. Biol., August 15, 2005; 25(16): 7120 - 7136. [Abstract] [Full Text] [PDF]

				S. L. Stone, H. Hauksdottir, A. Troy, J. Herschleb, E. Kraft, and J. Callis Functional Analysis of the RING-Type Ubiquitin Ligase Family of Arabidopsis Plant Physiology, January 1, 2005; 137(1): 13 - 30. [Abstract] [Full Text] [PDF]