Lab 1 Activities
- point 1
- point 2
- point 3
The Origin of Eukaryotes from Prokaryotes by Time and Genetic Distance
Nick Lane Energetics and genetics across the prokaryote-eukaryote divide. Biol. Direct: 2011, 6();35 PMID:21714941
Copyright ©2011 Lane; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Endosymbiotic origin of eukaryotes by time and genetic distance 
Research Article Using Confocal Microscopy
The aim of this study was to investigate and provide evidence to support the migration and morphological change of mesothelial cells during tissue injury response. By using confocal microscopy imaging Nagai and peers, 2013, were able to observe clearly delineated mesothelial cells within ex vivo mouse abdominal wall tissue culture, as well as transformed mesothelial cells (MeT5A) in in-vivo tissue culture and witness their morphological transition from flat cells to cuboidal cells. This transition was able to be observed as confocal microscope analysis allows for the control in the depth of field and eliminates/reduces background matter, so that mesothelial cells positioned on top of each other can be differentiated. In addition, these confocal microscopy techniques also allowed the researchers to observe the horizontal migration of these mesothelial cells across the tissue culture, moving through gaps between surrounding cells. These findings provided evidence in support of the change and migration of mesothelial cells during injury response. 
Lenart and co-workers (2003)examined the breakdown of the nuclear envelope in live starfish oocytes using various techniques involving fluorescently labeled dextrans (polysaccharides), membrane dyes and green fluorescently tagged proteins (GFP-tagged proteins), in conjunction with confocal time-lapse microscopy and electron microscopy which allowed them to view the changes in the oocyte nuclear envelope. Through the use of different sized fluorescently labelled dextran fractions experimenters were able to analyse the changes in the permeability of the nuclear envelope in maturing starfish oocytes. They firstly observed a sequential entry of dextran molecules, beginning with the smaller molecules entering the nucleus followed by larger molecules with diameters up to 40nm. The use of GFP-tagged nucleoporins revealed a corresponding gradual loss of peripheral nucleoporins from Nuclear Pore Complexes (NPC) (selective aqueous channels that span both nuclear membranes, connecting the nucleus with the cell cytoplasm) which resulted in the dilation of these channels from 10 to 40nm and a gradual release of import substrates. It was clearly noted, however, that the core of NPCs remained intact. Another key observation which was made was that the nuclear envelope structure remained unaffected. Next a rapid complete permeabilisation of the nuclear envelope that spread throughout the nuclear surface was noted, allowing macromolecules of diameters up to 100nm to enter the nucleus, this proposed the complete removal of the remaining core of the NPCs. It was also found that at the electron microscope level the nuclear envelope was fenestrated in the end. These experimenters therefore concluded that the breakdown of the nuclear envelope occurred in two distinct sequential phases: -Phase 1 involves the gradual disassembly of the NPCs, which coincides with an increase in nuclear membrane/envelope permeability allowing for some macromolecules to enter the nucleus and nuclear import substrates to leave. At the end of this first phase the nuclear envelope remains intact. -Phase 2 is characterised by an increase and rapid spreading nuclear envelope permeability as well as apparent fenestration of the nuclear envelope and hence its breakdown resulting from the removal of the core of NPCs. 
This research paper is relevant to the nuclear envelope breakdown section as it provides an experiment which clearly shows evidence of how the nuclear envelope gradually breaks down and explores the role of NPCs in this.