This Article Full Text Full Text (PDF) Supplemental Data All Versions of this Article: 143/3/1132    most recent pp.106.093864v1 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 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 (5) Citing Articles via Google Scholar Google Scholar Articles by Fujiki, Y. Articles by Ohsumi, Y. Search for Related Content PubMed PubMed Citation Articles by Fujiki, Y. Articles by Ohsumi, Y. Agricola Articles by Fujiki, Y. Articles by Ohsumi, Y.

CELL BIOLOGY AND SIGNAL TRANSDUCTION

An Arabidopsis Homolog of Yeast ATG6/VPS30 Is Essential for Pollen Germination^1,[W]

Department of Cell Biology, National Institute for Basic Biology, Okazaki 444–8585, Japan

Yeast (Saccharomyces cerevisiae) Atg6/Vps30 is required for autophagy and the sorting of vacuolar hydrolases, such as carboxypeptidase Y. In higher eukaryotes, however, roles for ATG6/VPS30 homologs in vesicle sorting have remained obscure. Here, we show that AtATG6, an Arabidopsis (Arabidopsis thaliana) homolog of yeast ATG6/VPS30, restored both autophagy and vacuolar sorting of carboxypeptidase Y in a yeast atg6/vps30 mutant. In Arabidopsis cells, green fluorescent protein-AtAtg6 protein localized to punctate structures and colocalized with AtAtg8, a marker protein of the preautophagosomal structure. Disruption of AtATG6 by T-DNA insertion resulted in male sterility that was confirmed by reciprocal crossing experiments. Microscopic analyses of AtATG6 heterozygous plants (AtATG6/atatg6) crossed with the quartet mutant revealed that AtATG6-deficient pollen developed normally, but did not germinate. Because other atatg mutants are fertile, AtAtg6 likely mediates pollen germination in a manner independent of autophagy. We propose that Arabidopsis Atg6/Vps30 functions not only in autophagy, but also plays a pivotal role in pollen germination.

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: Yoshinori Ohsumi (yohsumi{at}nibb).

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

www.plantphysiol.org/cgi/doi/10.1104/pp.106.093864

^* Corresponding author; e-mail yohsumi{at}nibb.ac.jp; fax 81–564–55–7516.

Received November 29, 2006; accepted January 12, 2007; published January 26, 2007.

This article has been cited by other articles:

				E. Itakura, C. Kishi, K. Inoue, and N. Mizushima Beclin 1 Forms Two Distinct Phosphatidylinositol 3-Kinase Complexes with Mammalian Atg14 and UVRAG Mol. Biol. Cell, December 1, 2008; 19(12): 5360 - 5372. [Abstract] [Full Text] [PDF]

				Y. Lee, E.-S. Kim, Y. Choi, I. Hwang, C. J. Staiger, Y.-Y. Chung, and Y. Lee The Arabidopsis Phosphatidylinositol 3-Kinase Is Important for Pollen Development Plant Physiology, August 1, 2008; 147(4): 1886 - 1897. [Abstract] [Full Text] [PDF]

				Z. Zhang, A. Lenk, M. X. Andersson, T. Gjetting, C. Pedersen, M. E. Nielsen, M.-A. Newman, B.-H. Hou, S. C. Somerville, and H. Thordal-Christensen A Lesion-Mimic Syntaxin Double Mutant in Arabidopsis Reveals Novel Complexity of Pathogen Defense Signaling Mol Plant, May 1, 2008; 1(3): 510 - 527. [Abstract] [Full Text] [PDF]

				A. R. Phillips, A. Suttangkakul, and R. D. Vierstra The ATG12-Conjugating Enzyme ATG10 Is Essential for Autophagic Vesicle Formation in Arabidopsis thaliana Genetics, March 1, 2008; 178(3): 1339 - 1353. [Abstract] [Full Text] [PDF]