Examination of gene expression in Mu insertion alleles of oil yellow1 during vegetative development in Zea mays

The <i>oil yellow1</i> ( <i>oy1</i> ) gene encodes the I subunit of magnesium chelatase, a key enzyme in chlorophyll biosynthesis in Z <i>ea mays</i> . Using Uniform <i>Mu</i> insertion lines, we examined how <i>Mu</i> insertions influence OY1 expression across vegetative development. Transcription remained unchanged during juvenile stages (V3-V5) but was consistently upregulated in adult stages (V7-V9). Related genes CHLD1 and CHLH1 showed similar patterns. Although transposon insertions often disrupt gene expression, our findings show they can also enhance transcription in a stage-specific manner.