Suppressive expression of the glutelin A1-collagen peptide fusion gene in hybrid rice lines with the mutant line, Low Glutelin Content-1 (LGC-1)
A low glutelin-content mutant, LGC-1, has a mutant gene (<i>lgc1</i>) comprising a tail-to-tail inverted repeat of two highly homologous glutelin B genes (<i>gluB4</i> and δ-<i>gluB5</i>), resulting in the production of double-stranded glutelin B RNA. Hybrid rice lines between LGC-1 and a transgenic line with the glutelin A1-collagen peptide fusion gene (<i>gluA1-coll</i>) were produced, and F<sub>2</sub> hybrid lines homozygous for each or both of the <i>gluA1-coll</i> and <i>lgc1</i> genes were selected. The expression of <i>gluA1-coll</i> in F<sub>2</sub> lines with <i>lgc1</i> was far lower than that of F<sub>2</sub> lines without <i>lgc1</i> at both the mRNA and protein levels as measured by semi-quantitative RT-PCR and immunoblotting using anti-collagen peptide antibody. The <i>gluA1</i> mRNA sequence alignment identical to the potential double-stranded RNA formed by <i>gluB4</i> sense and δ-<i>gluB5</i> antisense RNAs consisted of 14 nucleotides at most, and was not more than 23 even when one mismatch was allowed within the sequence. Thus, such shorter double-stranded glutelin B RNAs were suggested to suppress the expression of not only endogenous <i>gluA</i> genes as reported previously (Kusaba et al. 2003) but also the exogenous <i>gluA1-coll</i> in the hybrid lines.
- Plant biotechnology
Plant biotechnology 25(5), 465-471, 2008-12-01
Japanese Society for Plant Cell and Molecular Biology