Table 1. Summary of the retroviral constructs used.

Abbreviation	Gene symbol	Enzyme name	Vector (fluorescent protein)
A4	A4GALT	α1,4-galactosyltransferase	pMigR1g (EGFP)
B1	B3GALNT1	β1,3-N-acetyl-galactosaminyltransferase 1	pMigR1b (mTagBFP)
B5	B3GALT5	GlcNAc/GalNAc-β1,3-galactosyltransferase 5	pMigR1r (TagRFP657)
FS	Gbgt1	Forssman synthase	pMigR1r (TagRFP657)

Each enzyme corresponding to a gene symbol was abbreviated in the text and its cDNA introduced into retroviral vectors containing a different fluorescent protein (between parentheses).