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標題: 光訊息傳遞因子LZF1/BBX22參與阿拉伯芥幼苗發育之分子研究
LZF1/BBX22 conveys light signals for optimal seedling development in Arabidopsis
作者: 張瓊穗
Chang, Chiung-Swey Joanne
關鍵字: light
26S proteasome
出版社: 生物科技學研究所
引用: Achard, P., Liao, L., Jiang, C., Desnos, T., Bartlett, J., Fu, X., and Harberd, N.P. (2007). DELLAs contribute to plant photomorphogenesis. Plant Physiol 143, 1163-1172. Agresti, A. (1992). A survey of exact inference for contingency tables. Statistical Science 7, 131-177. Alabadi, D., Gallego-Bartolome, J., Orlando, L., Garcia-Carcel, L., Rubio, V., Martinez, C., Frigerio, M., Iglesias-Pedraz, J.M., Espinosa, A., Deng, X.W., and Blazquez, M.A. (2008). Gibberellins modulate light signaling pathways to prevent Arabidopsis seedling de-etiolation in darkness. Plant J 53, 324-335. Alonso, J.M., Stepanova, A.N., Leisse, T.J., Kim, C.J., Chen, H., Shinn, P., Stevenson, D.K., Zimmerman, J., Barajas, P., Cheuk, R., Gadrinab, C., Heller, C., Jeske, A., Koesema, E., Meyers, C.C., Parker, H., Prednis, L., Ansari, Y., Choy, N., Deen, H., Geralt, M., Hazari, N., Hom, E., Karnes, M., Mulholland, C., Ndubaku, R., Schmidt, I., Guzman, P., Aguilar-Henonin, L., Schmid, M., Weigel, D., Carter, D.E., Marchand, T., Risseeuw, E., Brogden, D., Zeko, A., Crosby, W.L., Berry, C.C., and Ecker, J.R. (2003). Genome-wide insertional mutagenesis of Arabidopsis thaliana. Science 301, 653-657. Al-Sady, B., Ni, W., Kircher, S., Schafer, E., and Quail, P.H. (2006). Photoactivated phytochrome induces rapid PIF3 phosphorylation prior to proteasome-mediated degradation. Mol Cell 23, 439-446. Ang, L.H., Chattopadhyay, S., Wei, N., Oyama, T., Okada, K., Batschauer, A., and Deng, X.W. (1998). Molecular interaction between COP1 and HY5 defines a regulatory switch for light control of Arabidopsis development. Mol Cell 1, 213-222. Ballesteros, M.L., Bolle, C., Lois, L.M., Moore, J.M., Vielle-Calzada, J.P., Grossniklaus, U., and Chua, N.H. (2001). LAF1, a MYB transcription activator for phytochrome A signaling. Genes Dev 15, 2613-2625. Barnes, S.A., Nishizawa, N.K., Quaggio, R.B., Whitelam, G.C., and Chua, N.H. (1996). Far-red light blocks greening of Arabidopsis seedlings via a phytochrome A-mediated change in plastid development. Plant Cell 8, 601-615. Berg, M., Rogers, R., Muralla, R., and Meinke, D. (2005). Requirement of aminoacyl-tRNA synthetases for gametogenesis and embryo development in Arabidopsis. Plant J 44, 866-878. Bernhardt, A., Lechner, E., Hano, P., Schade, V., Dieterle, M., Anders, M., Dubin, M.J., Benvenuto, G., Bowler, C., Genschik, P., and Hellmann, H. (2006). CUL4 associates with DDB1 and DET1 and its downregulation affects diverse aspects of development in Arabidopsis thaliana. Plant J 47, 591-603. Borevitz, J.O., Xia, Y., Blount, J., Dixon, R.A., and Lamb, C. (2000). Activation tagging identifies a conserved MYB regulator of phenylpropanoid biosynthesis. Plant Cell 12, 2383-2394. Brown, B.A., and Jenkins, G.I. (2008). UV-B signaling pathways with different fluence-rate response profiles are distinguished in mature Arabidopsis leaf tissue by requirement for UVR8, HY5, and HYH. Plant Physiol 146, 576-588. Buer, C.S., and Djordjevic, M.A. (2009). Architectural phenotypes in the transparent testa mutants of Arabidopsis thaliana. J Exp Bot 60, 751-763. Casal, J.J., Fankhauser, C., Coupland, G., and Blazquez, M.A. (2004). Signalling for developmental plasticity. Trends Plant Sci 9, 309-314. Casal, J.J., and Yanovsky, M.J. (2005). Regulation of gene expression by light. Int J Dev Biol 49, 501-511. Casazza, A.P., Rossini, S., Rosso, M.G., and Soave, C. (2005). Mutational and expression analysis of ELIP1 and ELIP2 in Arabidopsis thaliana. Plant Mol Biol 58, 41-51. Chang, S., Puryear, J., and Cainey, J. (1993). A simple and efficient method for isolating RNA from pine trees. Plant Mol Biol Rep 11, 113-116. Chang, C.S., Li, Y.H., Chen, L.T., Chen, W.C., Hsieh, W.P., Shin, J., Jane, W.N., Chou, S.J., Choi, G., Hu, J.M., Somerville, S., and Wu, S.H. (2008). LZF1, a HY5-regulated transcriptional factor, functions in Arabidopsis de-etiolation. Plant J 54, 205-219. Chattopadhyay, S., Ang, L.H., Puente, P., Deng, X.W., and Wei, N. (1998). Arabidopsis bZIP protein HY5 directly interacts with light-responsive promoters in mediating light control of gene expression. Plant Cell 10, 673-683. Chen, M., Chory, J., and Fankhauser, C. (2004). Light Signal Transduction in Higher Plants. Annu Rev Genet 38, 87-117. Chen, H., Shen, Y., Tang, X., Yu, L., Wang, J., Guo, L., Zhang, Y., Zhang, H., Feng, S., Strickland, E., Zheng, N., and Deng, X.W. (2006). Arabidopsis CULLIN4 Forms an E3 Ubiquitin Ligase with RBX1 and the CDD Complex in Mediating Light Control of Development. Plant Cell 18, 1991-2004. Chen, H., Zhang, J., Neff, M.M., Hong, S.W., Zhang, H., Deng, X.W., and Xiong, L. (2008). Integration of light and abscisic acid signaling during seed germination and early seedling development. Proc Natl Acad Sci USA 105, 4495-4500. Chen, H., Huang, X., Gusmaroli, G., Terzaghi, W., Lau, O.S., Yanagawa, Y., Zhang, Y., Li, J., Lee, J.H., Zhu, D., and Deng, X.W. (2010). Arabidopsis CULLIN4-damaged DNA binding protein 1 interacts with CONSTITUTIVELY PHOTOMORPHOGENIC1-SUPPRESSOR OF PHYA complexes to regulate photomorphogenesis and flowering time. Plant Cell 22, 108-123. Cheng, Y., Qin, G., Dai, X., and Zhao, Y. (2008). NPY genes and AGC kinases define two key steps in auxin-mediated organogenesis in Arabidopsis. Proc Natl Acad Sci U S A 105, 21017-21022. Cluis, C.P., Mouchel, C.F., and Hardtke, C.S. (2004). The Arabidopsis transcription factor HY5 integrates light and hormone signaling pathways. Plant J 38, 332-347. Collin, V., Lamkemeyer, P., Miginiac-Maslow, M., Hirasawa, M., Knaff, D.B., Dietz, K.J., and Issakidis-Bourguet, E. (2004). Characterization of plastidial thioredoxins from Arabidopsis belonging to the new y-type. Plant Physiol 136, 4088-4095. Danon, A., and Mayfield, S.P. (1991). Light regulated translational activators: identification of chloroplast gene specific mRNA binding proteins. EMBO J 10, 3993-4001. Danon, A., and Mayfield, S.P. (1994). Light-regulated translation of chloroplast messenger RNAs through redox potential. Science 266, 1717-1719. Datta, S., Hettiarachchi, G.H., Deng, X.W., and Holm, M. (2006). Arabidopsis CONSTANS-LIKE3 is a positive regulator of red light signaling and root growth. Plant Cell 18, 70-84. Datta, S., Johansson, H., Hettiarachchi, C., Irigoyen, M.L., Desai, M., Rubio, V., and Holm, M. (2008). LZF1/SALT TOLERANCE HOMOLOG3, an Arabidopsis B-box protein involved in light-dependent development and gene expression, undergoes COP1-mediated ubiquitination. Plant Cell 20, 2324-2338. Davis, S.J., and Vierstra, R.D. (1998). Soluble, highly fluorescent variants of green fluorescent protein (GFP) for use in higher plants. Plant Mol Biol 36, 521-528. de Lucas, M., Daviere, J.M., Rodriguez-Falcon, M., Pontin, M., Iglesias-Pedraz, J.M., Lorrain, S., Fankhauser, C., Blazquez, M.A., Titarenko, E., and Prat, S. (2008). A molecular framework for light and gibberellin control of cell elongation. Nature 451, 480-484. Deshaies, R.J., and Meyerowitz, E. (2000). COP1 patrols the night beat. Nat Cell Biol 2, E102-104. Dieterle, M., Zhou, Y.C., Schafer, E., Funk, M., and Kretsch, T. (2001). EID1, an F-box protein involved in phytochrome A-specific light signaling. Genes Dev 15, 939-944. Dowson-Day, M.J., and Millar, A.J. (1999). Circadian dysfunction causes aberrant hypocotyl elongation patterns in Arabidopsis. Plant J 17, 63-71. Duchene, A.M., Giritch, A., Hoffmann, B., Cognat, V., Lancelin, D., Peeters, N.M., Zaepfel, M., Marechal-Drouard, L., and Small, I.D. (2005). Dual targeting is the rule for organellar aminoacyl-tRNA synthetases in Arabidopsis thaliana. Proc Natl Acad Sci USA 102, 16484-16489. Edgar, R., Domrachev, M., and Lash, A.E. (2002). Gene Expression Omnibus: NCBI gene expression and hybridization array data repository. Nucleic Acids Res 30, 207-210. Ehlting, J., Buttner, D., Wang, Q., Douglas, C.J., Somssich, I.E., and Kombrink, E. (1999). Three 4-coumarate:coenzyme A ligases in Arabidopsis thaliana represent two evolutionarily divergent classes in angiosperms. Plant J 19, 9-20. Eisen, M.B., Spellman, P.T., Brown, P.O., and Botstein, D. (1998). Cluster analysis and display of genome-wide expression patterns. Proc Natl Acad Sci U S A 95, 14863-14868. Esmon, C.A., Tinsley, A.G., Ljung, K., Sandberg, G., Hearne, L.B., and Liscum, E. (2006). A gradient of auxin and auxin-dependent transcription precedes tropic growth responses. Proc Natl Acad Sci U S A 103, 236-241. Fairchild, C.D., Schumaker, M.A., and Quail, P.H. (2000). HFR1 encodes an atypical bHLH protein that acts in phytochrome A signal transduction. Genes Dev 14, 2377-2391. Felsenstein, J. (1985). Confidence limits on phylogenies: An approach using the bootstrap. Evolution 39, 783-791. Feng, S., Martinez, C., Gusmaroli, G., Wang, Y., Zhou, J., Wang, F., Chen, L., Yu, L., Iglesias-Pedraz, J.M., Kircher, S., Schafer, E., Fu, X., Fan, L.M., and Deng, X.W. (2008). Coordinated regulation of Arabidopsis thaliana development by light and gibberellins. Nature 451, 475-479. Franklin, K.A., and Whitelam, G.C. (2004). Light signals, phytochromes and cross-talk with other environmental cues. J Exp Bot 55, 271-276. Gelhaye, E., Rouhier, N., Navrot, N., and Jacquot, J.P. (2005). The plant thioredoxin system. Cell Mol Life Sci 62, 24-35. Genoud, T., Buchala, A.J., Chua, N.H., and Metraux, J.P. (2002). Phytochrome signalling modulates the SA-perceptive pathway in Arabidopsis. Plant J 31, 87-95. Gollub, J., Ball, C.A., Binkley, G., Demeter, J., Finkelstein, D.B., Hebert, J.M., Hernandez-Boussard, T., Jin, H., Kaloper, M., Matese, J.C., Schroeder, M., Brown, P.O., Botstein, D., and Sherlock, G. (2003). The Stanford Microarray Database: data access and quality assessment tools. Nucleic Acids Res 31, 94-96. Griffiths, S., Dunford, R.P., Coupland, G., and Laurie, D.A. (2003). The evolution of CONSTANS-like gene families in barley, rice, and Arabidopsis. Plant Physiol 131, 1855-1867. Guo, H., Duong, H., Ma, N., and Lin, C. (1999). The Arabidopsis blue light receptor cryptochrome 2 is a nuclear protein regulated by a blue light-dependent post-transcriptional mechanism. Plant J 19, 279-287. Harari-Steinberg, O., Ohad, I., and Chamovitz, D.A. (2001). Dissection of the light signal transduction pathways regulating the two early light-induced protein genes in Arabidopsis. Plant Physiol 127, 986-997. Hardtke, C.S., Gohda, K., Osterlund, M.T., Oyama, T., Okada, K., and Deng, X.W. (2000). HY5 stability and activity in arabidopsis is regulated by phosphorylation in its COP1 binding domain. EMBO J 19, 4997-5006. Heddad, M., Noren, H., Reiser, V., Dunaeva, M., Andersson, B., and Adamska, I. (2006). Differential expression and localization of early light-induced proteins in Arabidopsis. Plant Physiol 142, 75-87. Henriques, R., Jang, I.C., and Chua, N.H. (2009). Regulated proteolysis in light-related signaling pathways. Curr Opin Plant Biol 12, 49-56. Hoecker, U., Tepperman, J.M., and Quail, P.H. (1999). SPA1, a WD-repeat protein specific to phytochrome A signal transduction. Science 284, 496-499. Holm, M., and Deng, X.W. (1999). Structural organization and interactions of COP1, a light-regulated developmental switch. Plant Mol Biol 41, 151-158. Holm, M., Hardtke, C.S., Gaudet, R., and Deng, X.W. (2001). Identification of a structural motif that confers specific interaction with the WD40 repeat domain of Arabidopsis COP1. EMBO J 20, 118-127. Holm, M., Ma, L.G., Qu, L.J., and Deng, X.W. (2002). Two interacting bZIP proteins are direct targets of COP1-mediated control of light-dependent gene expression in Arabidopsis. Genes Dev 16, 1247-1259. Hong, S.H., Kim, H.J., Ryu, J.S., Choi, H., Jeong, S., Shin, J., Choi, G., and Nam, H.G. (2008). CRY1 inhibits COP1-mediated degradation of BIT1, a MYB transcription factor, to activate blue light-dependent gene expression in Arabidopsis. Plant J 55, 361-371. Hu, W., and Ma, H. (2006). Characterization of a novel putative zinc finger gene MIF1: involvement in multiple hormonal regulation of Arabidopsis development. Plant J 45, 399-422. Hu, W., Su, Y.S., and Lagarias, J.C. (2009). A light-independent allele of phytochrome B faithfully recapitulates photomorphogenic transcriptional networks. Mol Plant 2, 166-182. Hudson, M., Ringli, C., Boylan, M.T., and Quail, P.H. (1999). The FAR1 locus encodes a novel nuclear protein specific to phytochrome A signaling. Genes Dev 13, 2017-2027. Huq, E., Tepperman, J.M., and Quail, P.H. (2000). GIGANTEA is a nuclear protein involved in phytochrome signaling in Arabidopsis. Proc Natl Acad Sci USA 97, 9789-9794. Huq, E., and Quail, P.H. (2002). PIF4, a phytochrome-interacting bHLH factor, functions as a negative regulator of phytochrome B signaling in Arabidopsis. EMBO J 21, 2441-2450. Indorf, M., Cordero, J., Neuhaus, G., and Rodriguez-Franco, M. (2007). Salt tolerance (STO), a stress-related protein, has a major role in light signalling. Plant J 51, 563-574. Jang, I.C., Yang, J.Y., Seo, H.S., and Chua, N.H. (2005). HFR1 is targeted by COP1 E3 ligase for post-translational proteolysis during phytochrome A signaling. Genes Dev 19, 593-602. Jang, S., Marchal, V., Panigrahi, K.C., Wenkel, S., Soppe, W., Deng, X.W., Valverde, F., and Coupland, G. (2008). Arabidopsis COP1 shapes the temporal pattern of CO accumulation conferring a photoperiodic flowering response. EMBO J 27, 1277-1288. Jang, I.C., Henriques, R., Seo, H.S., Nagatani, A., and Chua, N.H. (2010). Arabidopsis PHYTOCHROME INTERACTING FACTOR proteins promote phytochrome B polyubiquitination by COP1 E3 ligase in the nucleus. Plant Cell 22, 2370-2383. Jiao, Y., Yang, H., Ma, L., Sun, N., Yu, H., Liu, T., Gao, Y., Gu, H., Chen, Z., Wada, M., Gerstein, M., Zhao, H., Qu, L.J., and Deng, X.W. (2003). A genome-wide analysis of blue-light regulation of Arabidopsis transcription factor gene expression during seedling development. Plant Physiol 133, 1480-1493. Jiao, Y., Ma, L., Strickland, E., and Deng, X.W. (2005). Conservation and divergence of light-regulated genome expression patterns during seedling development in rice and Arabidopsis. Plant Cell 17, 3239-3256. Jiao, Y., Lau, O.S., and Deng, X.W. (2007). Light-regulated transcriptional networks in higher plants. Nat Rev Genet 8, 217-230. Khanna, R., Kronmiller, B., Maszle, D.R., Coupland, G., Holm, M., Mizuno, T., and Wu, S.H. (2009). The Arabidopsis B-box zinc finger family. Plant Cell 21, 3416-3420. Kircher, S., Gil, P., Kozma-Bognar, L., Fejes, E., Speth, V., Husselstein-Muller, T., Bauer, D., Adam, E., Schafer, E., and Nagy, F. (2002). Nucleocytoplasmic partitioning of the plant photoreceptors phytochrome A, B, C, D, and E is regulated differentially by light and exhibits a diurnal rhythm. Plant Cell 14, 1541-1555. Kleine, T., Kindgren, P., Benedict, C., Hendrickson, L., and Strand, A. (2007). Genome-wide gene expression analysis reveals a critical role for CRYPTOCHROME1 in the response of Arabidopsis to high irradiance. Plant Physiol 144, 1391-1406. Koornneef, M., Rolff, E., and Spruit, C.J.P. (1980). Genetic control of light-inhibited hypocotyl elongation in Arabidopsis thaliana (L.) Heynh. Z. Pflanzenphysiologie 100, 147-160. Kruszka, K., Barneche, F., Guyot, R., Ailhas, J., Meneau, I., Schiffer, S., Marchfelder, A., and Echeverria, M. (2003). Plant dicistronic tRNA-snoRNA genes: a new mode of expression of the small nucleolar RNAs processed by RNase Z. EMBO J 22, 621-632. Kwon, Y.R., Lee, H.J., Kim, K.H., Hong, S.W., Lee, S.J., and Lee, H. (2008). Ectopic expression of Expansin3 or Expansinbeta1 causes enhanced hormone and salt stress sensitivity in Arabidopsis. Biotechnol Lett 30, 1281-1288. Lange, H., Shropshire, W., and Mohr, H. (1971). An analysis of phytochrome-mediated anthocyanin synthesis. Plant Physiol 47, 649-655. Lau, O.S., and Deng, X.W. (2010). Plant hormone signaling lightens up: integrators of light and hormones. Curr Opin Plant Biol 13, 1-7. Laubinger, S., Marchal, V., Le Gourrierec, J., Wenkel, S., Adrian, J., Jang, S., Kulajta, C., Braun, H., Coupland, G., and Hoecker, U. (2006). Arabidopsis SPA proteins regulate photoperiodic flowering and interact with the floral inducer CONSTANS to regulate its stability. Development 133, 3213-3222. Laxmi, A., Pan, J., Morsy, M., and Chen, R. (2008). Light plays an essential role in intracellular distribution of auxin efflux carrier PIN2 in Arabidopsis thaliana. PLoS One 3, e1510. Lee, Y.J., Kim, D.H., Kim, Y.W., and Hwang, I. (2001). Identification of a signal that distinguishes between the chloroplast outer envelope membrane and the endomembrane system in vivo. Plant Cell 13, 2175-2190. Lee, J., He, K., Stolc, V., Lee, H., Figueroa, P., Gao, Y., Tongprasit, W., Zhao, H., Lee, I., and Deng, X.W. (2007). Analysis of transcription factor HY5 genomic binding sites revealed its hierarchical role in light regulation of development. Plant Cell 19, 731-749. Leivar, P., Tepperman, J.M., Monte, E., Calderon, R.H., Liu, T.L., and Quail, P.H. (2009). Definition of early transcriptional circuitry involved in light-induced reversal of PIF-imposed repression of photomorphogenesis in young Arabidopsis seedlings. Plant Cell 21, 3535-3553. Leivar, P., and Quail, P.H. (2010). PIFs: pivotal components in a cellular signaling hub. Trends Plant Sci doi, 10.1016/j.tplants.2010.1008.1003 Li, J., Ou-Lee, T.M., Raba, R., Amundson, R.G., and Last, R.L. (1993). Arabidopsis flavonoid mutants are hypersensitive to UV-B irradiation. Plant Cell 5, 171-179. Lin, C., and Shalitin, D. (2003). Cryptochrome structure and signal transduction. Annu Rev Plant Biol 54, 469-496. Lin, R., and Wang, H. (2004). Arabidopsis FHY3/FAR1 gene family and distinct roles of its members in light control of Arabidopsis development. Plant Physiol 136, 4010-4022. Lin, J.F., and Wu, S.H. (2004). Molecular events in senescing Arabidopsis leaves. Plant J 39, 612-628. Lippuner, V., Cyert, M.S., and Gasser, C.S. (1996). Two classes of plant cDNA clones differentially complement yeast calcineurin mutants and increase salt tolerance of wild-type yeast. J Biol Chem 271, 12859-12866. Lisso, J., Steinhauser, D., Altmann, T., Kopka, J., and Mussig, C. (2005). Identification of brassinosteroid-related genes by means of transcript co-response analyses. Nucleic Acids Res 33, 2685-2696. Liu, X.L., Covington, M.F., Fankhauser, C., Chory, J., and Wagner, D.R. (2001). ELF3 encodes a circadian clock-regulated nuclear protein that functions in an Arabidopsis PHYB signal transduction pathway. Plant Cell 13, 1293-1304. Liu, L.J., Zhang, Y.C., Li, Q.H., Sang, Y., Mao, J., Lian, H.L., Wang, L., and Yang, H.Q. (2008). COP1-mediated ubiquitination of CONSTANS is implicated in cryptochrome regulation of flowering in Arabidopsis. Plant Cell 20, 292-306. Ma, L., Li, J., Qu, L., Hager, J., Chen, Z., Zhao, H., and Deng, X.W. (2001). Light control of Arabidopsis development entails coordinated regulation of genome expression and cellular pathways. Plant Cell 13, 2589-2607. Ma, L., Gao, Y., Qu, L., Chen, Z., Li, J., Zhao, H., and Deng, X.W. (2002). Genomic evidence for COP1 as a repressor of light-regulated gene expression and development in Arabidopsis. Plant Cell 14, 2383-2398. Ma, L., Zhao, H., and Deng, X.W. (2003). Analysis of the mutational effects of the COP/DET/FUS loci on genome expression profiles reveals their overlapping yet not identical roles in regulating Arabidopsis seedling development. Development 130, 969-981. McNellis, T.W., von Arnim, A.G., Araki, T., Komeda, Y., Misera, S., and Deng, X.W. (1994). Genetic and molecular analysis of an allelic series of cop1 mutants suggests functional roles for the multiple protein domains. Plant Cell 6, 487-500. Montgomery, B.L., Yeh, K.C., Crepeau, M.W., and Lagarias, J.C. (1999). Modification of distinct aspects of photomorphogenesis via targeted expression of mammalian biliverdin reductase in transgenic Arabidopsis plants. Plant Physiol 121, 629-639. Moran, R., and Porath, D. (1980). Chlorophyll Determination in Intact Tissues Using N,N-Dimethylformamide. Plant Physiol 65, 478-479. Nagy, F., and Schafer, E. (2002). Phytochromes control photomorphogenesis by differentially regulated, interacting signaling pathways in higher plants. Annu Rev Plant Biol 53, 329-355. Nemhauser, J.L., Hong, F., and Chory, J. (2006). Different plant hormones regulate similar processes through largely nonoverlapping transcriptional responses. Cell 126, 467-475. Nemhauser, J.L. (2008). Dawning of a new era: photomorphogenesis as an integrated molecular network. Curr Opin Plant Biol 11, 4-8. Ni, M., Tepperman, J.M., and Quail, P.H. (1998). PIF3, a phytochrome-interacting factor necessary for normal photoinduced signal transduction, is a novel basic helix-loop-helix protein. Cell 95, 657-667. Nozue, K., Covington, M.F., Duek, P.D., Lorrain, S., Fankhauser, C., Harmer, S.L., and Maloof, J.N. (2007). Rhythmic growth explained by coincidence between internal and external cues. Nature 448, 358-361. Osterlund, M.T., Wei, N., and Deng, X.W. (2000a). The roles of photoreceptor systems and the COP1-targeted destabilization of HY5 in light control of Arabidopsis seedling development. Plant Physiol 124, 1520-1524. Osterlund, M.T., Hardtke, C.S., Wei, N., and Deng, X.W. (2000b). Targeted destabilization of HY5 during light-regulated development of Arabidopsis. Nature 405, 462-466. Owens, D.K., Crosby, K.C., Runac, J., Howard, B.A., and Winkel, B.S. (2008). Biochemical and genetic characterization of Arabidopsis flavanone 3
摘要: “光”調控許多植物生長與發育的過程。不論是面對微小或是劇烈的“光”環境變化,植物都可以作出適當偵測與回應,讓植物可以在多變化的“光”環境中獲得最佳生長優勢。在自然環境中,在土壤中發芽的阿拉伯芥幼苗進行暗型態發育,藉由持續延長的下胚軸來突破土表。在適當的光照環境中,植物則會進行光型態發育並開始自營生活。植物藉由光受體分子來接受“光”訊息,並經由訊息傳導和轉錄體的調整來因應“光”環境的改變。目前針對這些“光”訊息傳遞因子的了解,大多來自突變株的篩選,而且幾乎所有的“光”訊息傳遞因子均作用於HY5—一個很重要的光訊息傳遞轉錄因子—的上游。是否有其它的光訊息傳遞轉錄因子,能承接從HY5來的光訊號,進而調控下游的光型態生長,仍屬未知;相關研究將可以進一步開拓我們對於“光”如何有效改變植物轉錄體的知識。 我們藉由比對野生型和hy5突變株的差異性基因表現,發現了一個尚未被研究過的C2C2-CO B-box轉錄調控因子—LZF1/BBX22。在光照環境下,HY5會直接結合至LZF1的啟動子來活化LZF1基因表現。針對LZF1的研究顯示:LZF1是一個“光”訊息的正向調控因子,透過活化下游的基因表現—例如MYB75及多個葉綠體蛋白質相關基因,來抑制下胚軸的延長,促進花青素的生合成及葉綠體的發育等幼苗發育歷程。在短日照環境中,LZF1也會抑制阿拉伯芥下胚軸在黑暗中的延長。 我們更進一步探討LZF1蛋白質在黑暗及特定的光照環境中受到差異性調控的特性。在暗型態及光型態發育中,轉錄及後轉譯作用同時精確的控制LZF1的轉錄子及蛋白質的量。不論在黑暗或光照下,LZF1蛋白質都會經由26S蛋白酶體調控而快速降解,LZF1蛋白質的半衰期介於二十與六十分鐘之間。在黑暗中,LZF1蛋白質的降解需要COP1但不需要HY5的參與。在光照下,HY5則會參與部分LZF1蛋白質的降解作用。當生長在黑暗或短日照下,過量的LZF1蛋白質的產生會造成cop1突變株過度進行光型態發育,不利幼苗的生長。過量的LZF1蛋白質也會影響光訊息及賀爾蒙訊息因子的基因表現。所以在黑暗及短日照下,正確調控LZF1蛋白質適時的降解與適當的累積對植物維持最佳的生長優勢是非常重要的。 本研究發現一個新的光訊息傳遞因子—LZF1,藉由承接HY5所帶來的光訊息,進一步改變轉錄體來調控下游的光型態生長。LZF1基因的轉錄子與蛋白質的總量均受到嚴格的控管,使得阿拉伯芥幼苗中的光訊息傳導得以順利執行,以達到最佳的幼苗生長狀態。
Light regulates multiple aspects of plant growth and development in plants. To achieve an optimal growth control, plants sophistically adjust their developmental programs in response to both the tiny changes of environmental light compositions and the rapid fluctuation of light intensities. In nature, plants proceed with skotomorphogenesis before emerging from the soil. When exposed to the light, plants start to use photomorphogenesis to establish the architecture in support of their autotrophic lives. Proper regulation of these processes is important for plants to achieve their optimal growth. It is known that transcriptomic changes govern the expression of signaling molecules upon the perception of light. However, the identifications of most light signaling molecules were from forward genetic studies and most of these molecules function upstream of HY5, an influential light signaling transcriptional regulator. The discovery of new component(s) conveying light signals from HY5 to photomorphogenic growth will no doubt broaden our knowledge of transcriptional cascades in light signaling pathways. I used global transcriptome comparisons to survey genes differentially expressed during early photomorphogenesis in wild-type but not in hy5 mutant. These gene expression data revealed LZF1 (light-regulated zinc finger protein 1)/BBX22, a gene encoding a previously uncharacterized C2C2-CO B-box transcriptional regulator, whose induction is both light-regulated and HY5-dependent. HY5 activates LZF1 via direct binding to LZF1 promoter. HY5 is necessary but not sufficient for the induction of LZF1. Functional studies indicate that LZF1 is a positive regulator for diverse light-mediated seedling growth, including the inhibition of hypocotyl elongation, anthocyanin biogenesis and chloroplast development. LZF1 achieves these functions via activating the expression of MYB75 and the genes encoding chloroplast proteins. In the absence of HY5, mutation of LZF1 leads to further reduced light sensitivity, supporting a possible synergistic impact of HY5 and LZF1 in Arabidopsis. We also confirmed that LZF1 enhances the inhibition of hypocotyl growth under short-day (SD) via attenuating the hypocotyl elongation during the dark-grown period. I also characterized the tight post-translational regulation of LZF1 in response to light/dark environment. We found the expression of LZF1 is tightly regulated at both the transcriptional and post-translational levels in skotomorphogenesis and during the process of de-etiolation. LZF1 is a short-lived protein degraded by 26S proteasome under both dark and light conditions. The degradation of LZF1 in the dark depends on the presence of COP1 but not HY5. The degradation of LZF1 in the light partially depends on HY5. To assess whether the rigid LZF1 degradation control is required for optimizing plant growth, we analyzed the seedling growth while LZF1 is over-produced in the cop1 mutant. The over-produced LZF1 negatively affects the Arabidopsis seedling development in the dark and short-day environments. Over-produced LZF1 exaggerates light-mediated seedling growth via regulating the expression of light and hormone-responsive genes. Therefore, the proper accumulation of LZF1 is crucial for plants to maintain optimal growth fitness when growing in the dark as well as under short-day. This research demonstrates that, by combining the rapid transcriptional activation and rigid surveillance of protein abundance via post-translational degradation, LZF1 functions to convey light signal from HY5 for an optimal seedling development in Arabidopsis.
其他識別: U0005-2910201001495900
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