Relationship between the control of glutamate chain lengths of folates and development.

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 elucidate the significance of glutamate chain lengths of folates, we examined expression patterns of GGH2 and GGH3, and discovered that GGH2 is co-expressed with GGH1 in most part of plants, whereas expression of GGH3 is limited in petiole of cotyledons. We also examined the effect of pteroyl mono- to octa- glutamate on Zinnia TE differentiation. Based on the data obtained, we will discuss the significance of poly-glutamated folates in maintaining stem cell status and role of GGH in differentiation.