Protocol Online logo
Top : Forum Archives: : Cell Biology

Selection of my cells-which methods? - (Mar/20/2005 )

It says that if I use antibiotica as the selection agent then it will take weeks or even months for selection, but if i cotransfect my cells with a plasmid that expresses a surface antigen then i can select my cells the day after transfection. Why does antibiotica selection take so long time? blink.gif

Thanks for ideas.

-seasons-

hi
for cells, you have two majors selactive antibiotics. Puromycin and neomycin.
Puromycin is a quick antibiotic, but could not be used with all cells.
Neomycin is acting on dividing cells. Therefore, selection could take a month!! But it's the more used.
You can see this topic for further info.

-fred_33-

QUOTE (fred_33 @ Mar 21 2005, 01:54 AM)
hi

Puromycin is a quick antibiotic, but could not be used with all cells.

What does it mean that it is quick?
How do i see if an antibiotica has a quick or slow effect?
I thought if i add an antibiotica on selective medium and after incubation if there are cells there then these cells are the selective ones. Is this the way it works for the mammalian cells?

QUOTE (fred_33 @ Mar 21 2005, 01:54 AM)
Neomycin is acting on dividing cells. Therefore, selection could take a month!! But it's the more used.

How come it becomes slow when it acts on dividing cells?

Thanks for any inputs.

-seasons-

hi
i mean by quick an antibiotic that allows rapid selection (three or 4 days are neccessary). Puromycin allows selection in two days, killing cells that are not transfected.

Neomycin is a poison that blocks the protein synthesis by binding to ribosome subnits. The result is abnormal proteins and finally the cell die. Therefore it acts on cells that ave good protein synthesis, and dividing cells are targeted more than non dividing cells. But it's not a directly "killing" process and such action requires long time to reach the death of non transfected cells.

QUOTE
I thought if i add an antibiotica on selective medium and after incubation if there are cells there then these cells are the selective ones. Is this the way it works for the mammalian cells?

That's actually the way to work with mammalian cells. But contrary to puromycin which ensure to have only transfected cells on the plate in less than a week, neomycin requires about one month to get the same results. sad.gif

-fred_33-