Volume 2, Issue 1, Pages 191-200 (January 2009) Shoot-Specific Down-Regulation of Protein Farnesyltransferase (α-Subunit) for Yield Protection against Drought in Canola  Wang Yang , Beaith Michelle , Chalifoux Maryse , Ying Jifeng , Uchacz Tina , Sarvas Carlene , Griffiths Rebecca , Kuzma Monika , Wan Jiangxin , Huang Yafan   Molecular Plant  Volume 2, Issue 1, Pages 191-200 (January 2009) DOI: 10.1093/mp/ssn088 Copyright © 2009 The Authors. All rights reserved. Terms and Conditions

Figure 1 Expression of AtHPR1 in Various Wild-Type Arabidopsis Tissues. Northern blot analysis was performed using total RNA isolated from young leaf, fully developed leaf (old leaf), stem, flower bud, open flower, root and silique. The blot was probed with a [32P]-labeled, double-stranded, full-length AtHPR1 cDNA probe. The transcript levels were normalized using β-tubulin as an internal control. Molecular Plant 2009 2, 191-200DOI: (10.1093/mp/ssn088) Copyright © 2009 The Authors. All rights reserved. Terms and Conditions

Figure 2 Sequence Structure of the Arabidopsis AtHPR1 Promoter and Expression Analysis of AtHPR1. (A) Several cis-acting elements in the nucleotide sequence of the AtHPR1 promoter were identified using the computer program PLACE. The two light-regulatory elements (I-box) are highlighted in red, the two Dof motifs are highlighted in purple, a core drought-responsive element (DRE) is marked with blue, and the ATG start codon of AtHPR1 is highlighted in green. The putative root expression repressing region of the promoter is highlighted in grey. (B–E) show the histochemical localization of GUS expression in the T2 seedling of Arabidopsis driven by the CaMV 35S promoter (B), the full-length AtHPR1 promoter (C), the truncated AtHPR1 promoter (D), and in the wild-type and the T1 seedling of AtHPR1::GUS transgenic canola (E). (F) Change in expression of AtHPR1 (open square), RD29A (open circle), and AtNCED3 (solid circle) in the leaf of wild-type Arabidopsis during a course of drought stress. Total RNA was isolated from the leaves of the plants on each of the water-withholding days for Northern blot analysis. The blot was probed with specific radio-labeled AtHPR1, RD29A, and AtNCED3 double-stranded cDNA probes. The transcript levels were normalized using β-tubulin as an internal control. Molecular Plant 2009 2, 191-200DOI: (10.1093/mp/ssn088) Copyright © 2009 The Authors. All rights reserved. Terms and Conditions

Figure 3 Shoot-Specific Down-Regulation of BnFTA in Canola. (A) Diagram of the AtHPR::hairpin-BnFTA construct. (B) Northern analysis of relative levels of endogenous BnFTA transcript in the wild-type (DH12075) and four T4 homozygous transgenic canola lines (BnFTA1–4). The blots were probed with a double-stranded BnFTA cDNA probe and the transcript levels were normalized using β-tubulin as an internal control. The error bars represent the standard errors from triplicate samples in three independent experiments. Molecular Plant 2009 2, 191-200DOI: (10.1093/mp/ssn088) Copyright © 2009 The Authors. All rights reserved. Terms and Conditions

Figure 4 Seed Yield (kg ha−1) of DH12075 Wild-Type Canola (WT) and Independent Transgenic Lines of BnFTA1, BnFTA2, BnFTA3, and BnFTA4 in the 2006 Summer Field Trials Conducted in Kipp (A) and Taber (B). The open bars represent mean seed yield for the optimal irrigation conditions, and the solid bars represent mean seed yield for the limited irrigation conditions for each entry. Standard errors of six replicates per field trial entry are shown for each mean. Asterisks above a bar indicate a significant difference (p < 0.1) between the trangenic BnFTA lines and the wild-type canola (LSD test). Molecular Plant 2009 2, 191-200DOI: (10.1093/mp/ssn088) Copyright © 2009 The Authors. All rights reserved. Terms and Conditions

Figure 5 A Schematic Model for Engineering Drought Tolerance and Yield Protection through Genetic Modulation of ABA-Mediated Stomatal Response. Enhanced ABA responsiveness in the guard cells can be achieved through inhibition of either the α-subunit (FTA) or the β-subunit (ERA1) of farnesyltransferase, or by down-regulation of the unknown substrates of farnesyltransferase (CaaX proteins). A number of positive and negative regulators of ABA hypersensitivity have been identified so for; however, it is not clear how they work together to regulate ABA sensing. Enhancement in guard cell ABA response can promote stomatal closure and direct reduction of transpiration, resulting in increased plant drought tolerance. Molecular Plant 2009 2, 191-200DOI: (10.1093/mp/ssn088) Copyright © 2009 The Authors. All rights reserved. Terms and Conditions