Cell-Specific Expression of Mitochondrial Transcripts in Maize Seedlings.
AUTOR(ES)
Li, XQ
RESUMO
Although mitochondria are thought to assume crucial and possibly novel physiological functions during male gametogenesis, it is not known to what extent mitochondrial function is necessary for other aspects of plant development or to what degree the expression of plant mitochondrial genes is subject to cell-specific regulation, particularly during vegetative growth. We have used in situ hybridization to show that extensive differences exist in the levels of mitochondrial RNAs (mtRNAs) among different tissues and among different individual cell types within the same organ of maize seedlings. The expression of all examined mtRNAs is enhanced in vascular bundles, particularly in procambium- and xylem-forming cells. Mitochondrial transcript levels correlated highly with cell division activity. For example, in roots, the transcripts are abundant in the dividing cells of the meristem but drop to very low levels in the nondividing cells of the root cap and the meristem quiescent center. By comparison, levels of functional mitochondria, as assessed by rhodamine-123 fluorescence, did not vary greatly among the same group of cells. In shoots, in situ hybridization and blot hybridization revealed differences in the patterns of localization among different mtRNAs. The results indicate that during vegetative growth, mitochondrial gene expression at the transcript level is subject to an unexpected degree of cell-specific regulation and that different controls may operate on different trancripts.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=161327Documentos Relacionados
- Cell-Specific Photosynthetic Gene Expression in Maize Determined Using Cell Separation Techniques and Hybridization in Situ1
- Male gametic cell-specific gene expression in flowering plants
- Maize sucrose synthase-1 promoter directs phloem cell-specific expression of Gus gene in transgenic tobacco plants.
- Cell-specific expression of transfected brain identifier repetitive DNAs.
- Cell-specific expression of alpha 1-antitrypsin in human intestinal epithelium.