Table 2.

Glucosylation of Man₉GlcNAc₂-P-P-dolichol in vitro depends upon Lec35 expression

Cell line	Doxycyclin (ng/ml)	UDPglucose	Glucosylation index		Glucosylation in presence of doxycyclin (%)
			Exp. 1	Exp. 2
CHO-K1	0	−	0.86	0.92
	10	−	0.85	0.91	99
6C	0	−	0.75	0.69
	10	−	0.51	0.33	58
CHO-K1	0	+	1.51	1.74
	10	+	1.66	1.88	109
6C	0	+	1.29	1.62
	10	+	0.71	0.48	41

As described under MATERIALS AND METHODS, CHO-K1 and 6C cells were treated with SLO, and incubated with GDP-[³H]mannose. Some experiments included a chase with 0.5 mM unlabeled UDP-glucose, as indicated. The LLO pool was recovered, and oligosaccharides released by mild acid hydrolysis were fractionated by HPLC. The HPLC data were used to calculate glucosylation indices. Results with two independent series of culture dishes are presented. The effect of doxycyclin treatment (final column) was calculated by dividing the average of the glucosylation indices obtained with doxycylin by the average of the indices obtained without doxycyclin, and is expressed as a percentage.