Methods and compositions for expressing an herbicide-tolerant polynucleotide

An expression cassette comprising a first polynucleotide that encodes a glyphosate-N-acetyltransferase polypeptide, wherein said polynucleotide is operably linked to:

• (a) a promoter that drives expression in a plant;
• and
• (b) at least one copy of the enhancer sequence set forth in SEQ ID NO:
• 72 or 85, or an enhancer sequence having at least 90% sequence identity to SEQ ID NO:
• 72 or 85, wherein said enhancer sequence modulates transcription and said enhancer sequence is heterologous to said promoter;
• wherein said expression cassette confers glyphosate tolerance on a monocot plant containing it, wherein said monocot plant is tolerant to glyphosate applied at a level effective to inhibit the growth of a control monocot plant which does not comprise said expression cassette.

A method for improving transformation efficiency, increasing a single copy integration event, or increasing transformation efficacy of a monocot plant comprising:

• a) introducing in the monocot plant a cassette comprising a polynucleotide encoding a glyphosate-N-acetyltransferase polypeptide, wherein said polynucleotide is operably linked to a promoter active in said monocot plant and is operably linked to at least one copy of the enhancer sequence set forth in SEQ ID NO:
• 72 or 85, or an enhancer sequence having at least 90% sequence identity to SEQ ID NO:
• 72 or 85, wherein said enhancer sequence modulates transcription and said enhancer sequence is heterologous to said promoter;
• b) contacting said monocot plant with an effective concentration of glyphosate;
• and,
• c) selecting the monocot plant expressing said polynucleotide.