Okushima, Y. et al. Functional genomic analysis of the AUXIN RESPONSE FACTOR gene family members in Arabidopsis thaliana: unique and overlapping functions of ARF7 and ARF19. Plant Cell 17, 444-463

Plant Gene Expression Center, Albany, California 94710, USA.
The Plant Cell (Impact Factor: 9.34). 03/2005; 17(2):444-63. DOI: 10.1105/tpc.104.028316
Source: PubMed


The AUXIN RESPONSE FACTOR (ARF) gene family products, together with the AUXIN/INDOLE-3-ACETIC ACID proteins, regulate auxin-mediated transcriptional activation/repression. The biological function(s) of most ARFs is poorly understood. Here, we report the identification and characterization of T-DNA insertion lines for 18 of the 23 ARF gene family members in Arabidopsis thaliana. Most of the lines fail to show an obvious growth phenotype except of the previously identified arf2/hss, arf3/ett, arf5/mp, and arf7/nph4 mutants, suggesting that there are functional redundancies among the ARF proteins. Subsequently, we generated double mutants. arf7 arf19 has a strong auxin-related phenotype not observed in the arf7 and arf19 single mutants, including severely impaired lateral root formation and abnormal gravitropism in both hypocotyl and root. Global gene expression analysis revealed that auxin-induced gene expression is severely impaired in the arf7 single and arf7 arf19 double mutants. For example, the expression of several genes, such as those encoding members of LATERAL ORGAN BOUNDARIES domain proteins and AUXIN-REGULATED GENE INVOLVED IN ORGAN SIZE, are disrupted in the double mutant. The data suggest that the ARF7 and ARF19 proteins play essential roles in auxin-mediated plant development by regulating both unique and partially overlapping sets of target genes. These observations provide molecular insight into the unique and overlapping functions of ARF gene family members in Arabidopsis.


Available from: Kazunari Arima
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    • "The tir1 mutant was obtained from the Arabidopsis Biological Stock Center. The slr and arf7-1 arf19-1 mutants have been described previously (Fukaki et al. 2002; Okushima et al. 2005; Copyright © 2015 The Japanese Society for Plant Cell and Molecular Biology Okushima et al. 2007). After being sterilized for 15 min with 95% ethanol, seeds were sown on a gellan gum plate ( "
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    • "Plants have to respond The mediator 304 TBP-containing and TBP-free-containing complexes implicated in transcription 305 13.5 Future directions and conclusions 306 References 307 Auxin is a phytohormone, which regulates plant developmental and physiological processes, such as tropic responses to light and gravity, general root and shoot architecture, embryogenesis , vascular differentiation and organogenesis (Woodward and Bartel, 2005). Genome-wide analysis studies show that the transcriptional response to an auxin is rapid and broad, influencing the gene expression of a large and different sets of genes (Goda et al., 2004; Okushima et al., 2005; Overvoorde et al., 2005; Nemhauser et al., 2006). Recent studies manifest that auxin homeostasis directly links growth regulation with stress adaptation responses. "
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    • "Factors (ARFs) (Okushima et al., 2005) and the Auxin/Indole-3-Acetic Acid (Aux/IAA) genes (Overvoorde et al., 2005), though a nontranscriptional pathway via AUXIN BINDING PROTEIN1 (ABP1) (Sauer and Kleine-Vehn, 2011) has also been identified. A subset of the ARFs are transcription factors that bind target promoters and activate auxin responsive genes, while in contrast the Aux/IAAs dimerise with ARFs and repress transcription (Guilfoyle and Hagen, 2007). "
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