FIGURE 2.

Expression of enzymes forming mucin-type O-glycans. Total RNA was isolated from proliferating and differentiated HT-29 and Caco-2 cells. Cells at 30–40% confluency were used as proliferating (Pro) cells, and 3 days after confluency cells were judged to be differentiated (Differ). In the case of HT-29 cells, culture media were changed to RPMI 1640 when it reached confluency. After reverse transcription, levels of cDNAs encoding enzymes were semi-quantitatively estimated by PCR (left panel). mRNA levels were normalized to that of glyceraldehyde phosphate dehydrogenase (GAPDH). Expression levels were assessed by the ImageJ program, and levels of each mRNA in differentiating cells were compared with that seen in proliferating cells (right panel).