Expression enhancing intron sequences

A recombinant DNA expression construct comprising:

• a) at least one promoter sequence functioning in plants or plant cells;
• b) at least one intron comprising a sequence selected from the group consisting of the sequences of SEQ ID NOs:
• 3, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, and 22, and functional equivalents thereof;
• and
• c) at least one nucleic acid sequence,
• wherein the at least one promoter sequence and at least one intron are functionally linked to the at least one nucleic acid sequence,
• wherein the at least one intron is heterologous to the at least one nucleic acid sequence and/or to the at least one promoter sequence, and
• wherein the functional equivalents thereof increase gene expression and comprise a sequence having at least 80% sequence identity to the full-length sequence of SEQ ID NO:
• 3, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, or 22 and comprise
• I) an intron length shorter than 1000 base pairs, and
• II) a 5′ splice site comprising the dinucleotide sequence 5′-GT-3′ (SEQ ID NO:
• 78), and
• III) a 3′ splice site comprising the trinucleotide sequence 5′-CAG-3′ (SEQ ID NO:
• 79), and
• IV) a branch point resembling the consensus sequence 5′-CURAY-3′ (SEQ ID NO:
• 75) upstream of the 3′ splice site.