Linked Life Data

15538652

Source:http://linkedlifedata.com/resource/pubmed/id/15538652

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2004-12-23
pubmed:abstractText
Seedlings of rice (Oryza sativa L. cv. Koshihikari and cv. Tan-ginbozu) were cultivated on board the Space Shuttle STS-95 mission and changes in the morphology and the cell wall properties of coleoptiles were analyzed. In space, rice coleoptiles showed a spontaneous (automorphic) curvature toward the caryopsis in the elongating region. The angle of automorphic curvature was larger in Koshihikari than in a gibberellin-deficient dwarf cultivar, Tan-ginbozu, and the angle gradually decreased during the growth of coleoptiles in both cultivars. The more quickly expanding convex side of the bending region of the rice coleoptiles showed a greater extensibility of the cell wall than the opposite side. There was a significant correlation between the angle of curvature and the difference in the cell wall extensibility between the convex and the concave sides. Both the levels of the cell wall polysaccharides per unit length of coleoptile and the ratio of high-molecular-mass polysaccharides in the hemicellulose fraction were lower in the convex side than the concave one. Also, the activity of (1-->3),(1-->4)-beta-glucanases in the cell wall was higher in the convex side than the concave one. These results suggest that the uneven modifications of cell wall metabolism bring about the difference in the levels and the molecular size of the cell wall polysaccharides, thereby causing the difference in capacity of the cell wall to expand between the dorsal and the ventral sides, leading to the automorphic curvature of rice coleoptiles in space. The data also suggest the involvement of gibberellins in inducing the automorphic curvature under microgravity conditions.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0918-9440
pubmed:author
pubmed:issnType
Print
pubmed:volume
117
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
449-55
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Cell wall changes involved in the automorphic curvature of rice coleoptiles under microgravity conditions in space.
pubmed:affiliation
Department of Biology, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan. hoson@sci.osaka-cu.ac.jp
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't