PREFERENTIAL TRANSCRIPTIONAL ACTIVITY OF A GLYCINE-RICH PROTEIN GENE FROM ARABIDOPSIS-THALIANA IN PROTODERM-DERIVED CELLS

Glycine-rich proteins (GRPs) are characterized by having the glycine r esidues arranged in characteristic repetitive structural motifs, but w ith distinct primary sequence. Although identified in various plant sp ecies, little is known about their contribution to the morphology and development of the organism. In this study we have isolated the atgrp- 5 gene encoding a glycine-rich protein from Arabidopsis thaliana. The promoter region of atgrp-5 was fused to the gus gene and the tissue ex pression pattern was analyzed in tobacco and A. thaliana transgenic pl ants. The chimeric gene displayed similar expression patterns in both species, showing preferential expression in protoderm-derived cells. A ctivity was also detected in the cortical parenchyma of A. thaliana in florescence axis and in the stem phloem of tobacco.