OPEN ACCESS ARTICLE

This Article Free via Open Access: OA OA Full Text Full Text (PDF) Supplemental Data OA All Versions of this Article: 150/3/1494    most recent pp.109.137950v1 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 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 Web of Science (2) Google Scholar Articles by Canino, G. Articles by Marchfelder, A. PubMed PubMed Citation Articles by Canino, G. Articles by Marchfelder, A. Agricola Articles by Canino, G. Articles by Marchfelder, A.

SYSTEMS BIOLOGY, MOLECULAR BIOLOGY, AND GENE REGULATION

Arabidopsis Encodes Four tRNase Z Enzymes^1,[W],[OA]

Molekulare Botanik, Universität Ulm, 89069 Ulm, Germany (G.C., E.B., J.F., S.B., A.M.); and Laboratoire Génome et Développement des Plantes, Université de Perpignan via Domitia-CNRS-IRD UMR 5096, 66860 Perpignan Cedex, France (N.B., M.E.)

Functional transfer RNA (tRNA) molecules are a prerequisite for protein biosynthesis. Several processing steps are required to generate the mature functional tRNA from precursor molecules. Two of the early processing steps involve cleavage at the tRNA 5' end and the tRNA 3' end. While processing at the tRNA 5' end is performed by RNase P, cleavage at the 3' end is catalyzed by the endonuclease tRNase Z. In eukaryotes, tRNase Z enzymes are found in two versions: a short form of about 250 to 300 amino acids and a long form of about 700 to 900 amino acids. All eukaryotic genomes analyzed to date encode at least one long tRNase Z protein. Of those, Arabidopsis (Arabidopsis thaliana) is the only organism that encodes four tRNase Z proteins, two short forms and two long forms. We show here that the four proteins are distributed to different subcellular compartments in the plant cell: the nucleus, the cytoplasm, the mitochondrion, and the chloroplast. One tRNase Z is present only in the cytoplasm, one protein is found exclusively in mitochondria, while the third one has dual locations: nucleus and mitochondria. None of these three tRNase Z proteins is essential. The fourth tRNase Z protein is present in chloroplasts, and deletion of its gene results in an embryo-lethal phenotype. In vitro analysis with the recombinant proteins showed that all four tRNase Z enzymes have tRNA 3' processing activity. In addition, the mitochondrial tRNase Z proteins cleave tRNA-like elements that serve as processing signals in mitochondrial mRNA maturation.

² Present address: The Byre, Keystone Barns, Loop Road, Keystone PE28 ORE, United Kingdom.

³ Present address: Institute of Zoology, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 230, 69120 Heidelberg, Germany.

The author responsible for distribution of materials integral to the findings presented in this article in accordance with the policy described in the Instructions for Authors (www.plantphysiol.org) is: Anita Marchfelder (anita.marchfelder{at}uni-ulm.de).

^[W] The online version of this article contains Web-only data.

^[OA] Open Access articles can be viewed online without a subscription.

www.plantphysiol.org/cgi/doi/10.1104/pp.109.137950

^* Corresponding author; e-mail anita.marchfelder{at}uni-ulm.de.

Received March 2, 2009; accepted April 26, 2009; published May 1, 2009.

This article has been cited by other articles:

				N. Barbezier, G. Canino, J. Rodor, E. Jobet, J. Saez-Vasquez, A. Marchfelder, and M. Echeverria Processing of a Dicistronic tRNA-snoRNA Precursor: Combined Analysis in Vitro and in Vivo Reveals Alternate Pathways and Coupling to Assembly of snoRNP Plant Physiology, July 1, 2009; 150(3): 1598 - 1610. [Abstract] [Full Text] [PDF]