Introns increase gene expression in cultured maize cells.

Area of Science:

• Plant molecular biology
• Gene expression regulation
• Biotechnology

Background:

• Investigating gene expression in maize (Zea mays L.) is crucial for crop improvement.
• Understanding the role of non-coding DNA elements like introns in gene regulation is essential.

Purpose of the Study:

• To determine the impact of introns on the expression of the maize alcohol dehydrogenase-1 (Adh1) gene.
• To identify the optimal location and effectiveness of introns in enhancing gene expression in maize cells.

Main Methods:

• Electroporation-mediated gene transfer of Adh1-S gene constructs into maize cells.
• Analysis of gene expression levels in stable and transient transformants.
• Utilizing chimeric genes with Adh1 regulatory elements and different coding regions.

Main Results:

• Introns significantly increase Adh1 gene expression, with intron 1 alone restoring expression to intact gene levels.
• Intron 1 enhances expression of chimeric genes by up to 100-fold when placed near the 5' end.
• Both Adh1 and Bronze1 introns stimulate expression from various promoters and coding regions.

Conclusions:

• Introns play a critical role in enhancing both endogenous and introduced gene expression in maize.
• The 5' region of the transcribed mRNA is the optimal location for intron-mediated expression enhancement.