Metabolism of 24-epi-castasterone and 24-epi-brassinolide in cell suspension cultures of Ornithopus sativus

Kolbe, A.; Schneider, Bernd; Porzel, Andrea; Adam, Günter

doi:10.1016/0031-9422(95)00546-3

Cited by 43 publications

(20 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These metabolites can be processed by modifications of the steroidal skeletons or side chains. The metabolic processes that inactivate bioactive BRs include dehydrogenation at C-3 and C-23 (Hai et al, 1996;Watanabe et al, 2000), epimerization at C-2, C-3, and C-24 (Suzuki et al, 1993;Nishikawa et al, 1995), hydroxylation at C-20, C-25, and C-26 (Voigt et al, 1993;Kolbe et al, 1996;Yokota et al, 1996), side chain cleavage at C-20/22 (Kolbe et al, 1996), and sulfonation at C-22 (Rouleau et al, 1999). In addition, active BRs are inactivated through conjugation by esterification at C-3 (Kolbe et al, 1995;Asakawa et al, 1996) and glycosylation at C-2, C-3, C-23, C-25, and C-26 (Bajguz, 2007).…”

Section: Bia1 Is a Bahd Acyltransferase-like Protein Involved In The mentioning

confidence: 99%

Genetic Evidence for the Reduction of Brassinosteroid Levels by a BAHD Acyltransferase-Like Protein in Arabidopsis

et al. 2012

View full text Add to dashboard Cite

Brassinosteroids (BRs) are a group of steroidal hormones involved in plant development. Although the BR biosynthesis pathways are well characterized, the BR inactivation process, which contributes to BR homeostasis, is less understood. Here, we show that a member of the BAHD (for benzylalcohol O-acetyltransferase, anthocyanin O-hydroxycinnamoyltransferase, anthranilate N-hydroxycinnamoyl/benzoyltransferase, and deacetylvindoline 4-O-acetyltransferase) acyltransferase family may play a role in BR homeostasis in Arabidopsis (Arabidopsis thaliana). We isolated two gain-of-function mutants, brassinosteroid inactivator1-1Dominant (bia1-1D) and bia1-2D, in which a novel BAHD acyltransferase-like protein was transcriptionally activated. Both mutants exhibited dwarfism, reduced male fertility, and deetiolation in darkness, which are typical phenotypes of plants defective in BR biosynthesis. Exogenous BR treatment rescued the phenotypes of the bia1-1D mutant. Endogenous levels of BRs were reduced in the bia1-1D mutant, demonstrating that BIA1 regulates endogenous BR levels. When grown in darkness, the bia1 loss-of-function mutant showed a longer hypocotyl phenotype and was more responsive to exogenous BR treatment than the wild-type plant. BIA1 expression was predominantly observed in the root, where low levels of BRs were detected. These results indicate that the BAHD acyltransferase family member encoded by BIA1 plays a role in controlling BR levels, particularly in the root and hypocotyl in darkness. Taken together, our study provides new insights into a mechanism that maintains BR homeostasis in Arabidopsis, likely via acyl conjugation of BRs.

show abstract

Section: Bia1 Is a Bahd Acyltransferase-like Protein Involved In The mentioning

confidence: 99%

Genetic Evidence for the Reduction of Brassinosteroid Levels by a BAHD Acyltransferase-Like Protein in Arabidopsis

et al. 2012

View full text Add to dashboard Cite

show abstract

“…(b) (22R,23R,24R)-2a,3a,22,23-Diisopropylidenedioxy-6,7-dioxo-6,7-seco-5a-ergostane 10 (130 mg, 65% (22R,23R,24R)-2a,3a,22,23-Diisopropylidenedioxy-6,7-seco-5a-ergostan-6,7-dioic acid (11) TEMPO (8.8 mg, 0.06 mmol) and phosphate buffer (2.74 ml, pH ¼ 6:88) were added to a solution of aldehyde 9 (316 mg, 0.55 mmol) in a mixture of THF (3 ml) and CH 3 CN (1.5 ml). (22R,23R,24R)-2a,3a,22,23-Diisopropylidenedioxy-Bhomo-7-oxa-5a-ergostan-6,7a-dione (12) Dicyclohexylcarbodiimide (25 mg, 0.12 mmol) was added to a solution of diacid 11 (48 mg, 0.08 mmol) in dry CH 2 Cl 2 (12 ml) under argon. After being stirred for 2 h at room temperature, the mixture was cooled to 08C, and the white precipitate was filtered and washed with CH 2 Cl 2 .…”

Section: Swern Oxidation Of Diol (8)mentioning

confidence: 99%

“…However, some metabolic transformations of BS can result in loss of the side chain. [11][12][13] In this respect, synthesis of BS bearing a label at a stable position in the cyclic part seems to be the preferred option. The present study investigated the synthesis of C-7 deuterium-labelled BS for biosynthetic studies.…”

Section: Introductionmentioning

confidence: 98%

Synthesis of [7,7‐²H₂]epibrassinolide

Хрипач

Khripach

Жабинский

et al. 2007

Labelled Comp Radiopharmac

View full text Add to dashboard Cite

Synthesis of labelled epibrassinolide containing two deuterium atoms in a position which is not subjected to isotopic exchange is reported. Key transformations include preparation of 6,7-seco steroidal diacid, its cyclization to a cyclic anhydride followed by a regioselective reduction with NaBD 4 . The obtained [7, H 2 ]epibrassinolide can be used in biochemical experiments when the loss of isotopic label should be avoided.

show abstract

“…castasterone to 3-epicastasterone [22], is con-sidered an inactivation step. Using 24-epicastasterone and 24-epibrassinolide, transformation to 3β -isomers was shown by cell suspension cultures of Ornithopus sativus [23]. Thus, inversion of configuration at C-3 is one of the putative possibilities to inactivate brassinolide, the most active brassinosteroid, but this specific reaction has not yet been experimentally demonstrated.…”

Section: Introductionmentioning

confidence: 99%

Reversible Conversion In The Brassinosteroid Quartet Castasterone, Brassinolide And Their 3β-Epimers

Antonchik¹,

Svatoš

Konstantinova³

et al. 2006

Zeitschrift Für Naturforschung B

View full text Add to dashboard Cite

The metabolism of deuterated brassinosteroids has been studied in excised leaves of Secale cereale, and in vitro in seedlings of Arabidopsis thaliana and cell suspension cultures of Lycopersicon esculentum. In addition to the known biosynthetic conversion of castasterone to brassinolide and epimerization to 3-epicastasterone, inversion of the 3α-configured hydroxyl group of brassinolide to a 3β -configured one in 3-epibrassinolide has been observed using liquid chromatography (HPLC) with electrospray ionization (ESI) and selected ion-monitoring mass-spectrometry (SIM-MS). Administration of deuterated 3-epicastasterone and 3-epibrassinolide to Arabidopsis and Secale seedlings resulted in the formation of castasterone and brassinolide, respectively, indicating conversion of configuration at C-3 of brassinosteroids is reversible.

show abstract

Metabolism of 24-epi-castasterone and 24-epi-brassinolide in cell suspension cultures of Ornithopus sativus

Cited by 43 publications

References 10 publications

Genetic Evidence for the Reduction of Brassinosteroid Levels by a BAHD Acyltransferase-Like Protein in Arabidopsis

Genetic Evidence for the Reduction of Brassinosteroid Levels by a BAHD Acyltransferase-Like Protein in Arabidopsis

Synthesis of [7,7‐²H₂]epibrassinolide

Reversible Conversion In The Brassinosteroid Quartet Castasterone, Brassinolide And Their 3β-Epimers

Contact Info

Product

Resources

About

Metabolism of 24-epi-castasterone and 24-epi-brassinolide in cell suspension cultures of Ornithopus sativus

Cited by 43 publications

References 10 publications

Genetic Evidence for the Reduction of Brassinosteroid Levels by a BAHD Acyltransferase-Like Protein in Arabidopsis

Genetic Evidence for the Reduction of Brassinosteroid Levels by a BAHD Acyltransferase-Like Protein in Arabidopsis

Synthesis of [7,7‐2H2]epibrassinolide

Reversible Conversion In The Brassinosteroid Quartet Castasterone, Brassinolide And Their 3β-Epimers

Contact Info

Product

Resources

About

Synthesis of [7,7‐²H₂]epibrassinolide