YUCCA6 over-expression demonstrates auxin function in delaying leaf senescence in Arabidopsis thaliana
AuthorsKim, Jeong Im
Murphy, Angus S.
Bressan, Ray A.
Narasimhan, Meena L.
KAUST DepartmentPlant Stress Genomics Research Lab
Permanent link to this recordhttp://hdl.handle.net/10754/325445
MetadataShow full item record
AbstractThe Arabidopsis thaliana YUCCA family of flavin monooxygenase proteins catalyses a rate-limiting step in de novo auxin biosynthesis. A YUCCA6 activation mutant, yuc6-1D, has been shown to contain an elevated free IAA level and to display typical high-auxin phenotypes. It is reported here that Arabidopsis plants over-expressing YUCCA6, such as the yuc6-1D activation mutant and 35S:YUC6 transgenic plants, displayed dramatic longevity. In addition, plants over-expressing YUCCA6 exhibited classical, delayed dark-induced and hormone-induced senescence in assays using detached rosette leaves. However, plants over-expressing an allele of YUCCA6, that carries mutations in the NADPH cofactor binding site, exhibited neither delayed leaf senescence phenotypes nor phenotypes typical of auxin overproduction. When the level of free IAA was reduced in yuc6-1D by conjugation to lysine, yuc6-1D leaves senesced at a rate similar to the wild-type leaves. Dark-induced senescence in detached leaves was accompanied by a decrease in their free IAA content, by the reduced expression of auxin biosynthesis enzymes such as YUCCA1 and YUCCA6 that increase cellular free IAA levels, and by the increased expression of auxin-conjugating enzymes encoded by the GH3 genes that reduce the cellular free auxin levels. Reduced transcript abundances of SAG12, NAC1, and NAC6 during senescence in yuc6-1D compared with the wild type suggested that auxin delays senescence by directly or indirectly regulating the expression of senescence-associated genes. 2011 The Author(s).
CitationKim JI, Murphy AS, Baek D, Lee S-W, Yun D-J, et al. (2011) YUCCA6 over-expression demonstrates auxin function in delaying leaf senescence in Arabidopsis thaliana. Journal of Experimental Botany 62: 3981-3992. doi:10.1093/jxb/err094.
PublisherOxford University Press (OUP)
JournalJournal of Experimental Botany
PubMed Central IDPMC3134353
- yucca6, a dominant mutation in Arabidopsis, affects auxin accumulation and auxin-related phenotypes.
- Authors: Kim JI, Sharkhuu A, Jin JB, Li P, Jeong JC, Baek D, Lee SY, Blakeslee JJ, Murphy AS, Bohnert HJ, Hasegawa PM, Yun DJ, Bressan RA
- Issue date: 2007 Nov
- Transgenic poplar expressing Arabidopsis YUCCA6 exhibits auxin-overproduction phenotypes and increased tolerance to abiotic stress.
- Authors: Ke Q, Wang Z, Ji CY, Jeong JC, Lee HS, Li H, Xu B, Deng X, Kwak SS
- Issue date: 2015 Sep
- SPOROCYTELESS modulates YUCCA expression to regulate the development of lateral organs in Arabidopsis.
- Authors: Li LC, Qin GJ, Tsuge T, Hou XH, Ding MY, Aoyama T, Oka A, Chen Z, Gu H, Zhao Y, Qu LJ
- Issue date: 2008
- The Thiol Reductase Activity of YUCCA6 Mediates Delayed Leaf Senescence by Regulating Genes Involved in Auxin Redistribution.
- Authors: Cha JY, Kim MR, Jung IJ, Kang SB, Park HJ, Kim MG, Yun DJ, Kim WY
- Issue date: 2016
- The biochemical mechanism of auxin biosynthesis by an arabidopsis YUCCA flavin-containing monooxygenase.
- Authors: Dai X, Mashiguchi K, Chen Q, Kasahara H, Kamiya Y, Ojha S, DuBois J, Ballou D, Zhao Y
- Issue date: 2013 Jan 18
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