125 research outputs found
Endoplasmic reticulum targeted GFP reveals ER organization in tobacco NT-1 cells during cell division
Author Posting. © The Authors, 2005. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Plant Physiology and Biochemistry, doi:10.1016/j.plaphy.2006.03.003.The endoplasmic reticulum (ER) of plant cells undergoes a drastic reorganization
during cell division. In tobacco NT-1 cells that stably express a GFP construct targeted
to the ER, we have mapped the reorganization of ER that occurs during mitosis and
cytokinesis with confocal laser scanning microscopy. During division, the ER and
nuclear envelope do not vesiculate. Instead, tubules of ER accumulate around the
chromosomes after the nuclear envelope breaks down, with these tubules aligning parallel
to the microtubules of the mitotic spindle. In cytokinesis, the phragmoplast is
particularly rich in ER, and the transnuclear channels and invaginations present in many
interphase cells appear to develop from ER tubules trapped in the developing
phragmoplast. Drug studies, using oryzalin and latrunculin to disrupt the microtubules
and actin microfilaments respectively, demonstrate that during division, the arrangement
of ER is controlled by microtubules and not by actin, which is the reverse of the situation
in interphase cells.Funding for this project included NASA grant # NAGW-4984 to the North
Carolina NSCORT (NASA Specialized Center of Research and Training) (SLG, DAC,
NSA), NSF REU Site Grant #0243930 (NSA), a Sigma Xi Grant-in-Aid Award (SLG),
and Australian Research Council Discovery Grant no. DP0208806 (DAC)
Electromagnetic wave propagation in rain and polarization effects
This paper summarizes our study on microwave and millimeter-wave propagation in rain with special emphasis on the effects of polarization. Starting from a recount of our past findings, we will discuss developments with these and how they are connected with subsequent research
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