title: The reduced plastid-encoded polymerase-dependent plastid gene expression leads to the delayed greening of the Arabidopsis fln2 mutant.
abstract: In Arabidopsis leaf coloration mutants, the delayed greening phenomenon is common. Nonetheless, the mechanism remains largely elusive. Here, a delayed greening mutant fln2-4 of FLN2 (Fructokinase-Like Protein2) was studied. FLN2 is one component of Transcriptionally Active Chromosome (TAC) complex which is thought to contain the complete plastid-encoded polymerase (PEP). fln2-4 displayed albino phenotype on medium without sucrose. The PEP-dependent plastid gene expression and chloroplast development were inhibited in fln2-4. Besides interacting with thioredoxin z (TRX z), we identified that FLN2 interacted with another two members of TAC complex in yeast including its homologous protein FLN1 (Fructokinase-Like Protein1) and pTAC5. This indicates that FLN2 functions in regulation of PEP activity associated with these TAC components. fln2-4 exhibited delayed greening on sucrose-containing medium. Comparison of the PEP-dependent gene expression among two complete albino mutants (trx z and ptac14), two yellow mutants (ecb2-2 and ys1) and the fln2-4 showed that fln2-4 remains partial PEP activity. FLN2 and FLN1 are the target proteins of TRX z involved in affecting the PEP activity. Together with the data that FLN1 could interact with itself in yeast, FLN1 may form a homodimer to replace FLN1-FLN2 as the TRX z target in redox pathway for maintaining partial PEP activity in fln2-4. We proposed the partial PEP activity in the fln2 mutant allowed plastids to develop into fully functional chloroplasts when exogenous sucrose was supplied, and finally the mutants exhibited green phenotype.
authors.affiliation: Department of Biology, College of Life and Environmental Sciences, Shanghai Normal University, Shanghai, P.R. China ; Department of Biology, School of Life Sciences, East China Normal University, Shanghai, P.R. China.
authors.forename: Chao
authors.initials: C
authors.lastname: Huang
authors.forename: Qing-Bo
authors.initials: QB
authors.lastname: Yu
authors.forename: Ruo-Hong
authors.initials: RH
authors.lastname: Lv
authors.forename: Qian-Qian
authors.initials: QQ
authors.lastname: Yin
authors.forename: Gen-Yun
authors.initials: GY
authors.lastname: Chen
authors.forename: Ling
authors.initials: L
authors.lastname: Xu
authors.forename: Zhong-Nan
authors.initials: ZN
authors.lastname: Yang
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D032461:Chromosomes, Plant; D003470:Culture Media; D015536:Down-Regulation; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D009154:Mutation; D018087:Plastids; D013395:Sucrose
chemical_list: D003470:Culture Media; D013395:Sucrose
references.citation: Proc Natl Acad Sci U S A. 2012 May 8;109(19):7541-6
references.pmid: 22529394
references.citation: Proc Natl Acad Sci U S A. 2009 Dec 15;106(50):21431-6
references.pmid: 19948955
references.citation: Plant Cell. 2006 Jan;18(1):176-97
references.pmid: 16326926
references.citation: Plant Cell. 2012 Jan;24(1):123-36
references.pmid: 22267485
references.citation: BMC Plant Biol. 2012 Jul 08;12:102
references.pmid: 22770232
references.citation: Proc Natl Acad Sci U S A. 2001 Aug 28;98(18):10499-504
references.pmid: 11526245
references.citation: Plant Cell. 2009 Apr;21(4):1109-28
references.pmid: 19376934
references.citation: Plant Cell. 1996 Apr;8(4):601-15
references.pmid: 8624438
references.citation: Annu Rev Plant Biol. 2006;57:739-59
references.pmid: 16669780
references.citation: Plant J. 2009 Sep;59(6):1011-23
references.pmid: 19500301
references.citation: Plant Cell. 2010 May;22(5):1498-515
references.pmid: 20511297
references.citation: Plant J. 2010 Oct;64(1):14-25
references.pmid: 20626654
references.citation: Eur J Biochem. 1985 Apr 15;148(2):207-12
references.pmid: 2580705
references.citation: Plant Physiol. 2009 Sep;151(1):114-28
references.pmid: 19587101
references.citation: Plant Cell. 2007 Oct;19(10):3157-69
references.pmid: 17921316
references.citation: Plant Cell. 2012 May;24(5):1984-2000
references.pmid: 22634759
references.citation: J Integr Plant Biol. 2011 Apr;53(4):258-69
references.pmid: 21294841
references.citation: Int Rev Cytol. 2005;244:1-68
references.pmid: 16157177
references.citation: Biochemistry. 1976 Jul 13;15(14):3039-45
references.pmid: 821516
references.citation: Plant Cell Physiol. 2010 Nov;51(11):1847-53
references.pmid: 20889507
references.citation: Plant Physiol. 2011 Nov;157(3):1043-55
references.pmid: 21949211
references.citation: EMBO J. 1996 Jun 3;15(11):2802-9
references.pmid: 8654377
references.citation: Plant Cell Physiol. 2000 Jan;41(1):68-76
references.pmid: 10750710
references.citation: Plant Cell. 2010 Oct;22(10):3423-38
references.pmid: 20978221
references.citation: Plant Cell. 2012 Mar;24(3):1081-95
references.pmid: 22415275
references.citation: Plant Physiol. 2011 Dec;157(4):1733-45
references.pmid: 22010110
references.citation: Plant Physiol. 2008 Jun;147(2):573-84
references.pmid: 18400937
references.citation: EMBO J. 1997 Jul 1;16(13):4041-8
references.pmid: 9233813
references.citation: Antioxid Redox Signal. 2003 Feb;5(1):79-87
references.pmid: 12626119
references.citation: Plant Cell. 2008 Nov;20(11):3148-62
references.pmid: 18996978
references.citation: FEBS Lett. 2003 Nov 27;555(1):40-4
references.pmid: 14630316
references.citation: Plant J. 2009 Apr;58(1):82-96
references.pmid: 19054358
references.citation: Plant Physiol. 2011 Apr;155(4):1545-51
references.pmid: 21330494
references.citation: Trends Genet. 2003 Jan;19(1):47-56
references.pmid: 12493248
references.citation: Plant Physiol. 2011 Apr;155(4):1477-85
references.pmid: 21205617
references.citation: Curr Genet. 1996 Dec;30(6):515-21
references.pmid: 8939813
references.citation: Physiol Plant. 2013 Jul;148(3):408-21
references.pmid: 23082802
references.citation: PLoS One. 2011;6(11):e26765
references.pmid: 22102866
references.citation: Plant Physiol. 2010 Mar;152(3):1297-308
references.pmid: 20097790
references.citation: Annu Rev Plant Physiol Plant Mol Biol. 1996 Jun;47:215-243
references.pmid: 15012288