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C Miller

Publications and source records attributed to C Miller.

At least 721 records · Page 40Linked to original sources
PubMed1972

Distribution and activation of the Golgi apparatus in geotropism.

We find a differential distribution of dictyosomes in the avascular tip cells of the oat (Avena sativa) coleoptile upon geostimulation. A differential activation (increased vesicle production) of the dictyosomes with respect to gravity also occurs, but only in the tip cells of the lower tissues. Similar differences in distribution and activation of dictyosomes occur also in cells subjacent to the avascular tip (1st and 5th millimeter from the apex) of both the upper and lower half-tissues. When only the outer epidermal cells below the apex are considered, the differential distribution and activation of dictyosomes occur only in the lower outer epidermis. The changes in distribution of dictyosomes begin at 6 minutes, or sooner, from the start of geostimulation, before the onset of geotropism. The kinetics of amyloplast sedimentation and Golgi movement do not appear to differ in the cells of the avascular tip. We suggest that the Golgi participates in, and possibly initiates, the differential elongation of cells of geotropically stimulated coleoptiles.

Journal Article↗
PubMed1972

Intracellular distribution of mitochondria after geotropic stimulation of the oat coleoptile.

The number of mitochondria is greater in the bottom than in the top of cells in geotropically stimulated oat (Avena sativa) coleoptiles. In the avascular tip and outer epidermis of subapical regions this difference occurs only in the lower tissues. These inequalities are found both in the KMnO(4) (-) and in the glutaraldehyde-fixed tissues; however, they are significant only in the former. Also, the number of mitochondria scored is consistently lower when the tissues were fixed in KMnO(4). These results suggest that mitochondria undergo a small degree of sedimentation after geostimulation, a redistribution reduced by the slower fixation with glutaraldehyde. Differences in mitochondrial number begin later than those in the amyloplast and the Golgi apparatus after geotropic stimulation. The cells in the avascular-tip region (a region having an important role in geotropism) have two to three times more mitochondria than the subapical cells.

Journal Article↗