Contour correspondence for serial section reconstruction: complex scenarios in palaeontology

In the hybrid Festuca scarisoa X drymeja where pairing is incomplete at pachytene, there is preferential pairing between the longer chromosomes of the complement. EM serial-section reconstruction of nuclei at zygotene and pachytene reveals that there is equally pronounced preferential pairing between larger centromeres. This evidence suggests that the longer chromosomes have large centromeres and that centromere volume is correlated with chromosome length. Confirmation of this comes from the comparison of the frequency distributions of observed centromere volumes and those predicted on the basis of chromosome length. Although there is a positive correlation between centromere volume and chromosome length, it is not possible to identify the centromeres of each individual chromosome within the complement because (a) the differences between the lengths of each chromosome are small and (b) the estimates of relative centromere volumes vary significantly between cells.

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Automated image segmentation and serial section reconstruction in microscopy

Journal of Microscopy ◽

10.1111/j.1365-2818.1990.tb02992.x ◽

1990 ◽

Vol 158 (2) ◽

pp. 187-196 ◽

Cited By ~ 11

Author(s):

V. A. Moss ◽

D. McEwan Jenkinson ◽

H. Y. Elder

Keyword(s):

Image Segmentation ◽

Serial Section ◽

Serial Section Reconstruction

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Structure of the Golgi and Distribution of Reporter Molecules at 20°C Reveals the Complexity of the Exit Compartments

Molecular Biology of the Cell ◽

10.1091/mbc.01-12-0593 ◽

2002 ◽

Vol 13 (8) ◽

pp. 2810-2825 ◽

Cited By ~ 94

Author(s):

Mark S. Ladinsky ◽

Christine C. Wu ◽

Shane McIntosh ◽

J. Richard McIntosh ◽

Kathryn E. Howell

Keyword(s):

Golgi Complex ◽

Serial Section ◽

Immunogold Labeling ◽

The Other ◽

Dominant Feature ◽

In Trans ◽

Golgi Structure ◽

Normal Thickness ◽

Em Tomography ◽

Serial Section Reconstruction

Incubating cells at 20°C blocks transport out of the Golgi complex and amplifies the exit compartments. We have used the 20°C block, followed by EM tomography and serial section reconstruction, to study the structure of Golgi exit sites in NRK cells. The dominant feature of Golgi structure in temperature-blocked cells is the presence of large bulging domains on the three trans-most cisternae. These domains extend laterally from the stack and are continuous with “cisternal” domains that maintain normal thickness and alignment with the other stacked Golgi cisternae. The bulging domains do not resemble the perpendicularly extending tubules associated with the trans-cisternae of control cells. Such tubules are completely absent in temperature-blocked cells. The three cisternae with bulging domains can be identified as trans by their association with specialized ER and the presence of clathrin-coated buds on the trans-most cisterna only. Immunogold labeling and immunoblots show a significant degradation of a medial- and a trans-Golgi marker with no evidence for their redistribution within the Golgi or to other organelles. These data suggest that exit from the Golgi occurs directly from three trans-cisternae and that specialized ER plays a significant role in trans-Golgi function.

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