Linked Life Data

9747538

Source:http://linkedlifedata.com/resource/pubmed/id/9747538

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1998-10-22
pubmed:abstractText
Cell suspension cultures of Ruta graveolens L. accumulate polyketide metabolites such as acridone alkaloids and flavonoid pigments. Whereas flavonoid synthesis is induced by light, the production of alkaloids can be enhanced in dark-cultured cells by treatment with fungal elicitors. Acridone synthase (ACS) catalyzes the committed condensing reaction of acridone biosynthesis yielding 1,3-dihydroxy-N-methylacridone from N-methylanthraniloyl- and malonyl-CoAs. The reaction proceeds in a manner analogous to that of chalcone synthase (CHS) which catalyzes the first committed step in flavonoid biosynthesis and cDNA and protein sequences of Ruta ACS possess a high degree of sequence homology to heterologous CHSs. ACS transcript abundance and specific activity were monitored in cultured R. graveolens cells irradiated either continuously with white light or treated with fungal elicitor over a period of 24 h and found to increase transiently upon elicitor treatment and to decrease upon light irradiation. Immunodetection with a rabbit polyclonal ACS antiserum revealed that the amounts of ACS polypeptide decreased slightly in light-irradiated cells but increased in elicitor-treated Ruta cells. Fluorescence microscopy and tissue print hybridizations were employed to aid in localizing the sites of storage and biosynthesis of acridone alkaloids in Ruta plants. Yellow fluorescing alkaloids were detected particularly in root tissue adjacent to the rhizodermis, but also in the endodermis and vascular tissue of the hypocotyl. ACS transcript abundance in situ followed the same spatial pattern, indicating that the synthesis of acridones likely proceeds at all sites of deposition rather than exclusively in the root. Expression in planta and the induction response of ACS suggest that the alkaloids serve as phytoanticipins or phytoalexins in the defense of Ruta particularly to soil-borne pathogens or as feeding deterrents.
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
49
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
403-11
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Differential regulation and distribution of acridone synthase in Ruta graveolens.
pubmed:affiliation
Biologisches Institut II, Lehrstuhl für Biochemie der Pflanzen, Albert-Ludwigs-Universität, Freiburg, Germany.
pubmed:publicationType
Journal Article