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891.
892.
Luiz Ricardo Hanai Eny Iochevet Segal Floh Maria Helena Pelegrinelli Fungaro Claudete Santa-Catarina Francine Matias de Paula Ana Maria Viana Maria Lucia Carneiro Vieira 《In vitro cellular & developmental biology. Plant》2010,46(4):368-377
Ocotea catharinensis is a rare tree species indigenous to the Atlantic rainforest of South America. In spite of its value as a hardwood species,
it is in danger of extinction. The species erratically produces seeds showing irregular flowering and slow growth. Therefore,
plants are not easily replaced. Tissue culture-based techniques are commonly used for obtaining living material for tree propagation
and in vitro preservation. Therefore, a high-frequency somatic embryogenic system was developed for the species. In the present work,
the genetic fidelity of cell aggregates and somatic embryos at various stages of in vitro development of O. catharinensis was investigated using RAPD and AFLP markers. Both analyses confirmed the absence of genetic variation in all developmental
stages of O. catharinensis embryogenic cultures, verifying that the in vitro system is genetically stable. The cultures were also analyzed for their methylation profiles at 5′-CCGG-3′ sites by identifying
methylation-sensitive amplification polymorphisms. Some of these markers differentiated cell aggregates from embryo bodies.
The sequencing of ten MSAP markers revealed that four sequences showed significant similarity to genes encoding plant proteins.
Particularly, the predicted amino acid sequence of the fragment designated as OcEaggHMttc155 was similar to the enzyme 1–aminocyclopropane-1-carboxylate oxidase (ACO), which is involved in the biosynthesis of ethylene,
and its expression was reported to occur from the beginning to the intermediate stages of plant embryo development. Here,
we suggest that this enzyme is possibly involved in the control of the earliest stages of somatic embryogenesis of O. catharinensis, and an approach to study ACO expression during somatic embryogenesis is proposed. 相似文献
893.
894.
Robert L. Carneiro 《American anthropologist》1997,99(1):204-205
Foundations of Social Inequality. T. Douglas Price and Gary M. Feinman. eds. New York: Plenum Press, 1995. 290 pp. 相似文献
895.