2. You have chosen Noam's clones for further characterization. You picked 15 of the clones, replated them in separate dishes and continued to grow them in the presence of G-418. When you obtained sufficient amounts of cells from each cell line (and after freezing samples of each cell line) you started the new analysis.
Cells of each cell line were transiently transfected with the following plasmid:

Each cell suspension was devided and plated to 2 different wells (G-418 and hygromycin was added to the medium). Two days later you added tetracyclin to one well from each cell line and added only the tet buffer (blank reagents) to the other well (to compare the GFP expression in induced vs. noninduced systems). After two more days you examined the cells in a confocal microscope.

Clone Number	+ TETRACYCLIN (Repressed expression)	- TETRACYCLIN (Induced expression)
Noam-1
Noam-6
Noam-7
Noam-10
Noam-13
Lior-15

Here are the results obtained from six different clones.
(Click on any clone number to get more details.)

Which of the following sentences is correct?
Choose between right and wrong.
Examine ALL answers

1. The tet-induced repression in Noam-1 cells is so tight that even in tet absence GFP is not expressed.
2. Noam -6 cells express the tet-element + reporter gene, but the tet control over the expression is so loose that maximal expression is achieved even in tet's presence.
3. Noam-7 cells are leaky. In spite of tet presence there is considerable expression of GFP, and the signal is only slightly increased in tet absence.
4. Noam-10 is the ideal cell line: the control over the expression is very tight, and the levels of induced expression are very high.
5. Noam-13 cell line is not too leaky, but due to plasmid incorporation in a non suitable location in the viral genome the induced expression is not efficient.
6. The initial cells of the Lior-15 clone survived due to inefficient exposure to G-418, but they did not incorporate the plasmid.