Abstract
Gamma-Glutamyl Hydorolase (GGH) cleaves the polyglutamate chain of folates. We have previously reported that GGH1 is expressed in procambial cells or meristematic tissues of mature plants, and that over-expression of any of three GGH genes or suppression of all GGH genes caused developmental defects. To assess whether GGH-mediated regulation of glutamate chain lengths of folates is involved in regulating meristematic activity, we analyzed expression pattern of GGH1 as well as effect of folate supplementation during callus induction and shoot regeneration from hypocotyl explants. The expression of GGH1 was suppressed in callus on callus inducing medium, while up-regulated in shoot inducing medium. Furthermore, pteroyl monoglutamate, but not pteroyl pentaglutamate, had shoot inducing activity. These results suggest significance of regulating glutamate chain lengths of folates in shoot development and involvement of GGHs in the process.
