Expression of human metallothionein-III confers protection against serum-free exposure of stably transfected Chinese hamster ovary CHO-K1 cells.
The cloned human metallothionein (MT)-III coding region was permanently transfected in Chinese hamster ovary (CHO-K1) cells in order to investigate the growth regulatory effects of this brain-specific protein. Reverse transcription-polymerase chain reaction (RT-PCR) experiments demonstrated stable expression of MT-III mRNA in CHO-K1/MT-III cells. Whereas in the presence of serum no differences were observed between the cell growth of both CHO-K1/MT-III and CHO-K1/pcDNA3-plasmid transfected cells, cell survival was attenuated differently in serum-free medium. CHO-K1/MT-III cells were more resistant (40 +/- 8%) to serum deprivation than pcDNA3-plasmid transfected cells. Recovery of cell growth for both cell lines was obtained by supplementing serum (0.25%), although with a different growth rate; half-maximal 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyl tetrazolium bromide (MTT)-conversion was observed between 5.1-5.7 and 4.2-4.5 days for CHO-K1/pcDNA3 and CHO-K1/MT-III cells, respectively. These results suggest a protective role for cloned human MT-III, besides its reported inhibitory and stimulatory effects on cell survival.
Amoureux
M C
MC
Laboratory of Cellular and Molecular Neurobiology, Centre de Recherche Pierre Fabre, Castres, France.
Wurch
T
T
Pauwels
P J
PJ
D000818:Animals; D001483:Base Sequence; D016466:CHO Cells; D002470:Cell Survival / Q000187:drug effects; D006224:Cricetinae; D016895:Culture Media, Serum-Free; D006801:Humans; D008668:Metallothionein / Q000096:biosynthesis*; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000096:biosynthesis; D014162:Transfection
D016895:Culture Media, Serum-Free; D012333:RNA, Messenger; D008668:Metallothionein