In a 2002 study, a standard curve was designed to show that there was a linear response between cell number and absorbance at 490nm. In a toxin concentration of 0.13µM, 50 percent of the insect cells had died in 48 hours, while all MCF-7 human cells survived. Even at a concentration as high as 1.3µM, the MCF-7 human cells were not impacted suggesting the cytoxicity of the toxin to human cells is extremely low. A change in morphology was also noted in the insect cells after the two days. At the beginning of the experiment, both insect and human cells were spherical in shape. Upon introducing the toxin into the growth media, many intrusions began appearing from the plasma membrane of the insect cells. These insect cells, then, broke into pieces very quickly. The speed of which is correlated with longer incubation times or with higher toxin concentrations in the media. However, the MCF-7 human cells showed no intrusions ore decomposition. In fact, the MCF-7 cells were morphologically unaffected meaning that the structure and form of the cell was uninfluenced by the presence of the toxin (Ji et al., …show more content…
Afterwards, the GNA mature peptide was taken apart by two restriction enzymes. Restriction enzymes have the property of cleaving DNA molecules at or near a specific sequences of bases. This GNA mature peptide is then cloned, and the AaIT is cloned after being amplified. The AaIT and the GNA containing KpnI and Sac I sites were cloned into a binary plant transformation expression vector pCAMBIA1301, which includes the maize promoter ubiquitin, nopaline synthase gene terminator, and hygromycin B resistance gene as a marker of selection, to create or generate the p1301-GNA, p1301-AaIT, and p1301-AaIT/GNA. These compositions were then transported into Agrobacterium tumefaciens using the strains EHA105, GV3101, and EHA105.The transgenic plants were then screened via hygromycin B selection. They were then further verified by the polymerase chain reaction analysis of genomic DNA to detect the appearance of the genes AaIT or GNA. Through this method, messenger RNA expression levels of AaIT and GNA were able to be analyzed. These plants were seen to be morphologically different from the wildtype plants. The transformations done on tobacco and rice were completed by co-cultivation. Co-cultivation means that both Agrobacterium tumefaciens and the plant embryos were cultivated in the same medium, or environment, and the explants were developed. (Liu et al.,