scholarly journals Isolation and identification of polar auxin transport inhibitors from Saussurea costus and Atractylodes japonica

2017 ◽  
Vol 70 (3) ◽  
Author(s):  
Yuta Toda ◽  
Hideyuki Shigemori ◽  
Junichi Ueda ◽  
Kensuke Miyamoto
Keyword(s):  
Auxin Transport ◽  
Polar Auxin Transport ◽  
Inhibitory Effects ◽  
Medicinal Species ◽  
Isolation And Identification ◽  
Naturally Occurring ◽  
Structure Activity ◽  
Atractylodes Japonica ◽  
Transport Inhibitors ◽  
Dehydrocostus Lactone

An intensive survey of naturally-occurring regulators of polar auxin transport (PAT) was conducted in two oriental medicinal species from the Asteraceae, <em>Saussurea costus</em> and <em>Atractylodes japonica</em>, using the radish hypocotyl bioassay system and physicochemical analyses. Costunolide and santamarine were identified as well as dehydrocostus lactone from <em>S. costus</em> roots, and atractylenolide II and (+)-eudesma-4(14),7(11)-dien-8-one from <em>Atractylodes japonica</em> rhizomes as physiologically novel compounds possessing inhibitory activities of PAT. Costunolide and santamarine showed ca. 40% inhibition of PAT in the radish hypocotyl segments at a dose of 2.5 μg/plant and 1 μg/plant, respectively. Inhibitory effects of atractylenolide II and (+)-eudesma-4(14),7(11)-dien-8-one were ca. 10 times lower than those of costunolide and santamarine. Structure–activity relationships and possible mechanisms to inhibit PAT are also discussed.

scholarly journals Dehydrocostus lactone, a naturally occurring polar auxin transport inhibitor, inhibits epicotyl growth by interacting with auxin in etiolated Pisum sativum seedlings

2019 ◽  
Vol 72 (3) ◽  
Author(s):  
Yuta Toda ◽  
Kazuho Okada ◽  
Junichi Ueda ◽  
Kensuke Miyamoto
Keyword(s):  
Auxin Transport ◽  
Sesquiterpene Lactones ◽  
Polar Auxin Transport ◽  
Stem Growth ◽  
Dependent Manner ◽  
Naturally Occurring ◽  
Pea Seedlings ◽  
Genes Encoding ◽  
Pea Epicotyl ◽  
Dehydrocostus Lactone

We have isolated germacranolide-type sesquiterpene lactones with an α-methylene-γ-lactone moiety, dehydrocostus lactone (DHCL), costunolide, santamarine, and a novel compound denoted artabolide [3-hydroxy-4,6,7(H)-germacra-1(10),11(13)-dien-6,12-olide] from oriental medicinal Asteraceae plants as novel naturally occurring inhibitors of polar auxin transport detected by the radish hypocotyl bioassay. To investigate the mode of action of natural sesquiterpene lactones on the inhibition of polar auxin transport as well as its relation to the growth of seedlings, the function of DHCL on growth and auxin dynamics in etiolated pea seedlings was studied intensively. DHCL reduced polar auxin transport in a dose-dependent manner together with the inhibition of the accumulation of mRNA of <em>PsAUX1</em> and <em>PsPIN1</em> genes encoding influx and efflux carrier proteins of auxin, respectively. DHCL applied to the apical hook region as a lanolin paste substantially inhibited elongation growth in the subapical region of epicotyls in intact etiolated pea seedlings, coupled with a significant reduction of endogenous levels of indole-3-acetic acid (IAA). DHCL also revealed the inhibition of IAA-induced cell elongation in etiolated pea epicotyl segments by affecting IAA-induced changes in the mechanical properties of cell walls. These facts suggest that germacranolide-type sesquiterpene lactones with an α-methylene-γ-lactone moiety affect the expression of <em>PsAUX1</em> and <em>PsPINs</em> genes, and then inhibit polar auxin transport and reduce endogenous levels of IAA necessary for stem growth in etiolated pea seedlings. These compounds are also suggested to show the inhibitory effects on auxin action in pea stem growth.

scholarly journals Ethylene Does Not Promote Adventitious Root Initiation on Apple Microcuttings

1996 ◽  
Vol 121 (5) ◽  
pp. 880-885 ◽  
Author(s):  
James F. Harbage ◽  
Dennis P. Stimart
Keyword(s):  
Carboxylic Acid ◽  
Auxin Transport ◽  
Adventitious Rooting ◽  
Polar Auxin Transport ◽  
Root Initiation ◽  
Ethylene Evolution ◽  
Basal Section ◽  
Naphthylphthalamic Acid ◽  
Transport Inhibitors

We investigated the role of ethylene on adventitious rooting of `Gala' (easy-to-root) and `Triple Red Delicious' (difficult-to-root) apple (Malus domestica Borkh.) microcuttings. Root count increased significantly as IBA level increased, with highest root counts on `Gala'. Ethylene evolution increased significantly with IBA level without significant differences between cultivars. Basal section removal of microcuttings in the area of root origin reduced root count without changing ethylene evolution. Ethylene treatment of proliferated shoots before microcutting excision failed to enhance rooting. IBA-induced ethylene evolution was eliminated nearly by AVG, but root count remained IBA dependent. ACC reversed IBA plus AVG rooting inhibition, but ACC alone failed to influence root count. Polar auxin transport inhibitors NPA and TIBA stimulated ethylene evolution without increasing root count. Adventitious rooting of apple microcuttings was not associated with ethylene. Chemical names used: 1-H-indole-3-butyric acid (IBA); aminoethoxyvinylglycine (AVG); 1-aminocyclopropane-1-carboxylic acid (ACC); 2,3,5-triiodobenzoic acid (TIBA); N-1-naphthylphthalamic acid (NPA).

Auxin Transport Inhibitors. II. 2-(1-Pyrenol)Benzoic Acid, a Potent Inhibitor of Polar Auxin Transport

1977 ◽  
Vol 4 (3) ◽  
pp. 321 ◽  
Author(s):  
GF Katekar ◽  
AE Geissler
Keyword(s):  
Benzoic Acid ◽  
Auxin Transport ◽  
Indoleacetic Acid ◽  
Potent Inhibitor ◽  
Polar Auxin Transport ◽  
Active Inhibitor ◽  
Polar Transport ◽  
Highly Active ◽  
Transport Inhibitors ◽  
Auxin Transport Inhibitors

2-(1-Pyrenoyl)benzoic acid is shown to be a highly active inhibitor of auxin transport by its ability to prevent the polar transport of indoleacetic acid in bean petioles. It is comparable in activity to other known auxin transport inhibitors, and also affects apical dominance and the geotropic and phototropic responses.

scholarly journals Synthesis of Moracin C and Its Derivatives with a 2-arylbenzofuran Motif and Evaluation of Their PCSK9 Inhibitory Effects in HepG2 Cells

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1327
Author(s):  
Jagadeesh Nagarajappa Masagalli ◽  
Melanayakanakatte Kuberappa BasavanaGowda ◽  
Hee-Sung Chae ◽  
Won Jun Choi
Keyword(s):  
Hepg2 Cells ◽  
Low Density Lipoprotein ◽  
Ldl Receptor ◽  
Density Lipoprotein ◽  
Direct Interaction ◽  
Inhibitory Effects ◽  
Low Density Lipoprotein Cholesterol ◽  
Naturally Occurring ◽  
Structure Activity ◽  
Key Factor

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a key factor in several cardiovascular diseases, as it is responsible for the elevation of circulating low-density lipoprotein cholesterol (LDL-C) levels in blood plasma by direct interaction with the LDL receptor. The development of orally available drugs to inhibit this PCSK9-LDLR interaction is a highly desirable objective. Here, we report the synthesis of naturally occurring moracin compounds and their derivatives with a 2-arylbenzofuran motif to inhibit PCSK9 expression. In addition, we discuss a short approach involving the three-step synthesis of moracin C and a divergent method to obtain various analogs from one starting material. Among the tested derivatives, compound 7 (97.1%) was identified as a more potent inhibitor of PCSK9 expression in HepG2 cells than berberine (60.9%). These results provide a better understanding of the structure–activity relationships of moracin derivatives for the inhibition of PCSK9 expression in human hepatocytes.

scholarly journals The PINOID protein kinase regulates organ development in Arabidopsis by enhancing polar auxin transport

Development ◽  
2001 ◽  
Vol 128 (20) ◽  
pp. 4057-4067 ◽  
Author(s):  
René Benjamins ◽  
Ab Quint ◽  
Dolf Weijers ◽  
Paul Hooykaas ◽  
Remko Offringa
Keyword(s):  
Protein Kinase ◽  
Auxin Transport ◽  
Vascular Tissue ◽  
Primary Root ◽  
Ectopic Expression ◽  
Polar Auxin Transport ◽  
Fine Tuning ◽  
35S Promoter ◽  
Serine Threonine Kinase ◽  
Transport Inhibitors

Arabidopsis pinoid mutants show a strong phenotypic resemblance to the pin-formed mutant that is disrupted in polar auxin transport. The PINOID gene was recently cloned and found to encode a protein-serine/threonine kinase. Here we show that the PINOID gene is inducible by auxin and that the protein kinase is present in the primordia of cotyledons, leaves and floral organs and in vascular tissue in developing organs or proximal to meristems. Overexpression of PINOID under the control of the constitutive CaMV 35S promoter (35S::PID) resulted in phenotypes also observed in mutants with altered sensitivity to or transport of auxin. A remarkable characteristic of high expressing 35S::PID seedlings was a frequent collapse of the primary root meristem. This event triggered lateral root formation, a process that was initially inhibited in these seedlings. Both meristem organisation and growth of the primary root were rescued when seedlings were grown in the presence of polar auxin transport inhibitors, such as naphthylphtalamic acid (NPA). Moreover, ectopic expression of PINOID cDNA under control of the epidermis-specific LTP1 promoter provided further evidence for the NPA-sensitive action of PINOID. The results presented here indicate that PINOID functions as a positive regulator of polar auxin transport. We propose that PINOID is involved in the fine-tuning of polar auxin transport during organ formation in response to local auxin concentrations.

Isolation and identification of plant growth-promoting bacteria associated with tall fescue

2009 ◽  
pp. 211-216 ◽  
Author(s):  
J. Monk ◽  
E. Gerard ◽  
S. Young ◽  
K. Widdup ◽  
M. O'Callaghan
Keyword(s):  
New Zealand ◽  
Plant Growth ◽  
Tall Fescue ◽  
Festuca Arundinacea ◽  
Plant Growth Promoting Bacteria ◽  
Beneficial Bacteria ◽  
Isolation And Identification ◽  
Naturally Occurring ◽  
Plant Growth Promoting ◽  
Growth Promoting

Tall fescue (Festuca arundinacea) is a useful alternative to ryegrass in New Zealand pasture but it is slow to establish. Naturally occurring beneficial bacteria in the rhizosphere can improve plant growth and health through a variety of direct and indirect mechanisms. Keywords: rhizosphere, endorhiza, auxin, siderophore, P-solubilisation

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