ILR1 and sILR1 IAA amidohydrolase homologs differ in expression pattern and substrate specificity

Campanella, James J.; Ludwig-Mueller, Jutta; Bakllamaja, Vinela; Sharma, Vipul; Cartier, Ania

doi:10.1023/b:grow.0000007501.27878.aa

Cited by 33 publications

(32 citation statements)

References 20 publications

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“…Although the enzymatic hydrolysis of IBA conjugates has not been previously described in the literature, it is unclear whether this activity is unique to monocots. Hydrolases from other plant species, such as A. suecica (sILR1; Campanella et al, 2003d) and M. truncatula (MtIAR32; J. J. Campanella, J. Ludwig-Mü ller, and S. Wexler, unpublished data) tested so far have little or no activity against IBA-Ala and others have not been reported.…”

Section: Discussionmentioning

confidence: 99%

“…Enzyme preparation and enzyme assays with TaIAR3 were expressed in E. coli (Campanella et al, 2003d). After collecting the bacterial cells by centrifugation for 10 min at 8,000g, the pellet was resuspended in 100 mL lysozyme buffer per initial 1 mL bacterial culture (30 mM Tris-HCl, pH 8.0, containing 1 mM EDTA, 20% Suc, and 1 mg mL 21 lysozyme [Sigma]) for cell lysis and incubated for 10 min at 4°C.…”

Section: Enzyme Preparation From Bacteriamentioning

confidence: 99%

“…ex O.E. Schulz (Campanella et al, 2003a(Campanella et al, , 2003d Article, publication date, and citation information can be found at www.plantphysiol.org/cgi …”

mentioning

confidence: 99%

“…ex O.E. Schulz (Campanella et al, 2003a(Campanella et al, , 2003d. Amidohydrolase homologs have also been isolated from Brassica rapa (Schuller and Ludwig-Mü ller, 2002).…”

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confidence: 99%

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A Novel Auxin Conjugate Hydrolase from Wheat with Substrate Specificity for Longer Side-Chain Auxin Amide Conjugates

et al. 2004

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This study investigates how the ILR1-like indole acetic acid (IAA) amidohydrolase family of genes has functionally evolved in the monocotyledonous species wheat (Triticum aestivum). An ortholog for the Arabidopsis IAR3 auxin amidohydrolase gene has been isolated from wheat (TaIAR3). The TaIAR3 protein hydrolyzes negligible levels of IAA-Ala and no other IAA amino acid conjugates tested, unlike its ortholog IAR3. Instead, TaIAR3 has low specificity for the ester conjugates IAA-Glc and IAAmyoinositol and high specificity for the conjugates of indole-3-butyric acid (IBA-Ala and IBA-Gly) and indole-3-propionic-acid (IPA-Ala) so far tested. TaIAR3 did not convert the methyl esters of the IBA conjugates with Ala and Gly. IBA and IBA conjugates were detected in wheat seedlings by gas chromatography-mass spectrometry, where the conjugate of IBA with Ala may serve as a natural substrate for this enzyme. Endogenous IPA and IPA conjugates were not detected in the seedlings. Additionally, crude protein extracts of wheat seedlings possess auxin amidohydrolase activity. Temporal expression studies of TaIAR3 indicate that the transcript is initially expressed at day 1 after germination. Expression decreases through days 2, 5, 10, 15, and 20. Spatial expression studies found similar levels of expression throughout all wheat tissues examined.In vascular plants, auxins, primarily indole-3-acetic acid (IAA), regulate gene expression, cell division, and cell elongation and differentiation in plant tissue. Auxins also affect vascularization, phototropism, geotropism, fruit development, flower development, and apical dominance (Davies, 1995). While IAA in low concentrations stimulates growth and development, higher concentrations can be toxic to the plant (Bandurski et al., 1995). Therefore, tight control of IAA concentration is necessary for proper plant development.IAA is stored in conjugated forms that are mostly considered to be inactive. Two main types of conjugated molecules have been studied: the amide-linked IAA forms bound to one or more amino acids and the ester-linked forms primarily bound to a sugar(s). These two types of conjugates appear to be found at varying concentrations in the diverse tissues of angiosperms (Domagalski et al., 1987). On average, 95% of all IAA in a plant is conjugated into these storage forms (Cohen and Bandurski, 1982;Bandurski et al., 1995;Campanella et al., 1996;Walz et al., 2002).There have been a variety of amide conjugates found in the plants studied to date. IAA-Asp has been identified as a natural conjugate in Scots pine (Pinus sylvestris; Andersson and Sandberg, 1982) and, together with IAA-Glu, in cucumber (Sonner and Purves, 1985) and soybean (Cohen, 1982). IAA-Ala has been detected in Picea abies Karst (Ö stin et al., 1992). Additionally, IAA-Ala, IAA-Asp, IAA-Leu, and IAA-Glu have been detected in Arabidopsis L. Heynh (Tam et al., 2000;Kowalczyk and Sandberg, 2001), although recent data suggest that IAA peptides may account for the majority of amide conjugates in this and other plant ...

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Section: Discussionmentioning

confidence: 99%

Section: Enzyme Preparation From Bacteriamentioning

confidence: 99%

“…ex O.E. Schulz (Campanella et al, 2003a(Campanella et al, , 2003d Article, publication date, and citation information can be found at www.plantphysiol.org/cgi …”

mentioning

confidence: 99%

“…ex O.E. Schulz (Campanella et al, 2003a(Campanella et al, , 2003d. Amidohydrolase homologs have also been isolated from Brassica rapa (Schuller and Ludwig-Mü ller, 2002).…”

mentioning

confidence: 99%

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A Novel Auxin Conjugate Hydrolase from Wheat with Substrate Specificity for Longer Side-Chain Auxin Amide Conjugates

et al. 2004

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“…For GC-MS, the following conditions were used applying a Varian Saturn 2100 ion-trap (Varian): 70 eV, electron impact ionization, column Phenomenex ZB-5 column (Phenomenex), 30 m 3 0.25 mm, 0.25-mm film thickness, injection temperature 2508C, trap temperature 2008C (Campanella et al, 2003); helium 1 mL min 21 ; splitless injection; for higher sensitivity, the mSIS mode was used (Wells and Huston, 1995); the column temperature program was: 1 min 708C, 208C min 21 to 2808C, 5 min 2808C, the retention time of methyl ester of IAA was10.81 min. MS fragments at m/z 136 (standard IAA) and at m/z 130 (native IAA) were used for quantification.…”

Section: Microarray Analysismentioning

confidence: 99%

Agrobacterium tumefaciensPromotes Tumor Induction by Modulating Pathogen Defense inArabidopsis thaliana

et al. 2009

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Agrobacterium tumefaciens causes crown gall disease by transferring and integrating bacterial DNA (T-DNA) into the plant genome. To examine the physiological changes and adaptations during Agrobacterium-induced tumor development, we compared the profiles of salicylic acid (SA), ethylene (ET), jasmonic acid (JA), and auxin (indole-3-acetic acid [IAA]) with changes in the Arabidopsis thaliana transcriptome. Our data indicate that host responses were much stronger toward the oncogenic strain C58 than to the disarmed strain GV3101 and that auxin acts as a key modulator of the ArabidopsisAgrobacterium interaction. At initiation of infection, elevated levels of IAA and ET were associated with the induction of host genes involved in IAA, but not ET signaling. After T-DNA integration, SA as well as IAA and ET accumulated, but JA did not. This did not correlate with SA-controlled pathogenesis-related gene expression in the host, although high SA levels in mutant plants prevented tumor development, while low levels promoted it. Our data are consistent with a scenario in which ET and later on SA control virulence of agrobacteria, whereas ET and auxin stimulate neovascularization during tumor formation. We suggest that crosstalk among IAA, ET, and SA balances pathogen defense launched by the host and tumor growth initiated by agrobacteria.

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Auxin as a Mediator of Abiotic Stress Responses

Salopek‐Sondi

Pavlović

Smolko

et al. 2017

Mechanism of Plant Hormone Signaling Under Stress

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ILR1 and sILR1 IAA amidohydrolase homologs differ in expression pattern and substrate specificity

Cited by 33 publications

References 20 publications

A Novel Auxin Conjugate Hydrolase from Wheat with Substrate Specificity for Longer Side-Chain Auxin Amide Conjugates

A Novel Auxin Conjugate Hydrolase from Wheat with Substrate Specificity for Longer Side-Chain Auxin Amide Conjugates

Agrobacterium tumefaciensPromotes Tumor Induction by Modulating Pathogen Defense inArabidopsis thaliana

Auxin as a Mediator of Abiotic Stress Responses

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