Abstract
In rice (Oryza sativa L.), two genes for cytosolic glutamine synthetase (GS1;1, GS1;2) were previously isolated. Another gene (GS1;3) in rice genome database and designed.
RT-PCR showed that mRNA for both GS1;1 and GS1;2 were detected in roots, leaf sheaths, leaf blades, and spikelets. However, the GS1;3 mRNA was only detected in spikelets. GS1;1 knock-out mutants, in which retrotransposon Tos17 was inserted into the 8th exon of GS1;1 gene, contained less amount of GS1 protein in roots and leaf blades than the wild type. Immunolocalization revealed that GS1 protein was accumulated in the similar regions of vascular tissues of root and leaves in both the mutant and wild-tipe. In the spikelets, the localization of GS1 protein in the mutant was located in different cell-types from Nipponbare, suggesting that GS1;2 and/or GS1;3 proteins were detected in the mutants.
