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

The oil yellow1 ( oy1 ) gene encodes the I subunit of magnesium chelatase, a key enzyme in chlorophyll biosynthesis in Z ea mays . Using Uniform Mu insertion lines, we examined how Mu 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.