PubMed · 4606318
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
R Baserga. 1974. Cell growth.. https://doi.org/10.1016/s0005-8165(74)80179-4
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
The kinetics of the delayed luminescence arising from correlated coherent many-soliton states in low-dimensional macromolecular systems, is calculated and shown to be different from the one arising from independent soliton states. The correlation between coherent electron states is essential at relatively high levels of excitation in the presence of very long macromolecules in a system. These conditions can be fulfilled in such biological systems, like algae Acetabularia Acetabulum. The cytoskeleton of this unicellular alga contains macromolecular structures (actin filaments, microtubules, etc.) of the length of several hundreds angstroms and more, in which many-soliton coherent states can exist. Indeed, the correlated coherent model is shown to give better fit of the experimental data for this type of algae in a wide range of intensities of the stimulating light, as compared with the model of noncorrelated solitons. The nonlinearity of the dependence of delayed luminescence intensity on the level of excitation increases with the increase of correlation between solitons.
In the juvenile stage, the diploid giant-celled green algae Acetabularia spp. are differentiated into an upright stalk and an irregularly branched rhizoid. Early amputation and grafting experiments as well as biochemical and molecular analyses have shown that mRNA (as poly(A)+ RNA) is continuously supplied from the primary nucleus in the rhizoid and accumulates in the stalk apex. In the present study, localization of poly(A)+ RNA in the juvenile stage of the Acetabularia peniculus was investigated by fluorescent in situ hybridization using oligo(dT) as a probe. The signal was localized in the apical cytoplasm and, in addition, multiple longitudinal striations throughout the stalk and rhizoid cytoplasm. A large portion of the poly(A)+ RNA striations exhibited structural polarity, broadened at one end and gradually thinned toward the other end. Some of the striations in the rhizoid cytoplasm were continuous with a zone of signal in the area of the perinuclear rim. The poly(A)+ RNA striations were associated with thick bands of longitudinal actin bundles which run through the entire length of the stalk. Cytochalasin D caused fragmentation of the actin bundles and irregular distribution of the fluorescent signal. We suggest that the poly(A)+ RNA striations constitute a hitherto unknown form of packaged mRNA that is transported over large distances along the actin cytoskeleton to be stored and expressed in the growing apex.
Explore the source record for details and available documents.