Linked Life Data

11524117

Source:http://linkedlifedata.com/resource/pubmed/id/11524117

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2001-8-28
pubmed:abstractText
In cultured Solanum glaucophyllum we have recently described the operation of a light-independent pathway of 1alpha,25-dihydroxy-vitamin D(3) (1alpha,25(OH)(2)D(3)) biosynthesis which involves similar intermediates as in vertebrates. In this work we investigated factors influencing the formation of 1alpha,25(OH)(2)D(3) and related sterols in S. glaucophyllum grown in vitro in darkness. Callus tissue and cells cultured in Murashige and Skoog medium in the absence of light were employed. Lipids were extracted with chloroform-methanol. The remaining water soluble fraction was incubated with beta-glucosidase to release vitamin D(3) compounds from their glycoconjugated derivatives followed by organic solvent extraction. Vitamin D(3) derivatives were isolated by Sephadex LH-20 and high-performance liquid chromatography (HPLC). HPLC or competitive protein binding assays with intestine 1alpha,25(OH)(2)D(3) receptor and serum vitamin D binding protein were used to quantify the metabolites. The levels of 1alpha,25(OH)(2)D(3) in calli varied according to the tissue explant origin, e.g. stem>leaf>fruit. For all organs, the metabolite was mainly present as free sterol (>80% of total). There were larger amounts of 25(OH)D(3) than 1alpha,25(OH)(2)D(3). It was found that Ca(2+), auxin and kinetin are important factors upregulating 1alpha,25(OH)(2)D(3) synthesis in S. glaucophyllum tissue and cells. Irradiation with UV light increased vitamin D(3) but not 1alpha,25(OH)(2)D(3) levels. In agreement with these results, incubation of cells with [3H]25(OH)D(3) revealed a low conversion rate to [3H]1alpha,25(OH)(2)D(3). The operation of a light-dependent pathway formation of vitamin D(3) coupled to higher expression of 25(OH)D(3)-1alpha-hydroxylase may account for the large concentrations of 1alpha,25(OH)(2)D(3) normally found in differentiated field-grown plants.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0031-9422
pubmed:author
pubmed:issnType
Print
pubmed:volume
58
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
81-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Effect of culture conditions on the synthesis of vitamin D(3) metabolites in Solanum glaucophyllum grown in vitro.
pubmed:affiliation
Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur. San Juan 670, 8000 Bahia Blanca, Argentina.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't