This Article Full Text Full Text (PDF) All Versions of this Article: 17/5/1585    most recent tpc.105.031518v1 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 (11) Citing Articles via Google Scholar Google Scholar Articles by Yamasato, A. Articles by Tanaka, A. Search for Related Content PubMed PubMed Citation Articles by Yamasato, A. Articles by Tanaka, A. Agricola Articles by Yamasato, A. Articles by Tanaka, A.

The N-Terminal Domain of Chlorophyllide a Oxygenase Confers Protein Instability in Response to Chlorophyll b Accumulation in Arabidopsis

^a Institute of Low Temperature Science, Hokkaido University, Sapporo, 060-0819 Japan
^b Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Kawaguchi, 332-0012 Japan

¹ To whom correspondence should be addressed. E-mail ayumi{at}lowtem.hokudai.ac.jp; fax 81-11-706-5493.

Plants acclimate to variations in light intensity by changing the antenna size of photosystems. This acclimation allows them to undergo efficient photosynthesis and creates a protective strategy to minimize photodamage. Chlorophyll b synthesis by chlorophyllide a oxygenase (CAO) is a key regulatory step in the control of antenna size. Recently, we found that higher plant CAOs consist of three domains (A, B, and C domains) and confirmed that the C domain possesses catalytic function. To investigate the function of the A domain, we fused various combinations of these three domains with green fluorescent protein (GFP) and introduced them into Arabidopsis thaliana. When a full-length CAO-GFP fusion protein was introduced into a chlorophyll b–less chlorina1-1 mutant, chlorophyll b accumulated to almost the same levels as in the chlorophyll b–containing Columbia wild type, but the CAO-GFP could not be detected by immunoblotting. By contrast, when a GFP-C domain fusion was introduced into chlorina1-1 or Columbia wild type, a large amount of GFP-C domain protein accumulated and the chlorophyll a/b ratio decreased drastically from 3.6 to 2.2 in Columbia wild type. When an A domain-GFP was introduced into Columbia wild type, A domain-GFP levels were very low. Conversely, a large amount of the protein accumulated when it was introduced into the chlorina1-1 mutant. These results indicate that the A domain may sense the presence of chlorophyll b and regulate the accumulation of CAO protein in the chloroplasts.

This article has been cited by other articles:

				Y. Sakuraba, R. Tanaka, A. Yamasato, and A. Tanaka Determination of a Chloroplast Degron in the Regulatory Domain of Chlorophyllide a Oxygenase J. Biol. Chem., December 25, 2009; 284(52): 36689 - 36699. [Abstract] [Full Text] [PDF]

				S. Bartsch, J. Monnet, K. Selbach, F. Quigley, J. Gray, D. von Wettstein, S. Reinbothe, and C. Reinbothe Three thioredoxin targets in the inner envelope membrane of chloroplasts function in protein import and chlorophyll metabolism PNAS, March 25, 2008; 105(12): 4933 - 4938. [Abstract] [Full Text] [PDF]

				T. Farmaki, M. Sanmartin, P. Jimenez, M. Paneque, C. Sanz, G. Vancanneyt, J. Leon, and J. J. Sanchez-Serrano Differential distribution of the lipoxygenase pathway enzymes within potato chloroplasts J. Exp. Bot., February 1, 2007; 58(3): 555 - 568. [Abstract] [Full Text] [PDF]

				M. Hirashima, S. Satoh, R. Tanaka, and A. Tanaka Pigment Shuffling in Antenna Systems Achieved by Expressing Prokaryotic Chlorophyllide a Oxygenase in Arabidopsis J. Biol. Chem., June 2, 2006; 281(22): 15385 - 15393. [Abstract] [Full Text] [PDF]

				C. Reinbothe, S. Bartsch, L. L. Eggink, J. K. Hoober, J. Brusslan, R. Andrade-Paz, J. Monnet, and S. Reinbothe A role for chlorophyllide a oxygenase in the regulated import and stabilization of light-harvesting chlorophyll a/b proteins PNAS, March 21, 2006; 103(12): 4777 - 4782. [Abstract] [Full Text] [PDF]