Expression data from mouse insulinoma cells

We previously isolated a subclone, MIN6 clone 4, from the parental MIN6 cells, that shows well-regulated insulin secretion in response to glucose, glybenclamide, and KCl, even after prolonged culture. To investigate the molecular mechanisms responsible for preserving GSIS in this subclone, we compared four groups of MIN6 cells: Pr-LP (parental MIN6, low passage number), Pr-HP (parental MIN6, high passage number), C4-LP (MIN6 clone 4, low passage number), and C4-HP (MIN6 clone 4, high passage number). Based on their capacity for GSIS, we designated the Pr-LP, C4-LP, and C4-HP cells as “responder cells.” In a DNA microarray analysis, we identified a group of genes with high expression in responder cells (“responder genes”), but extremely low expression in the Pr-HP cells. MIN6 clone 4 cells are a subclone isolated from low-passage-number parental MIN6 cells by the limiting dilution method (JM, unpublished). This subclone was maintained in the same culture conditions as the parental cells, and retained good GSIS even after 6 months of continuous culture. For the low-passage-number parental MIN6 cells (Pr-LP), we used cells passaged 17-20 times; for the high-passage-number MIN6 cells (Pr-HP), we used cells passaged 35-40 times. Seventeen to 20 passages were also used for the low-passage-number MIN6 clone 4 cells (C4-LP), and the high-passage ones (C4-HP) were used after 40 to 50 passages.