Gene cassettes
The DNA insertion contain the following two gene cassettes:
1) Escherichia coli hygromycin B phosphotransferase (hph); and
2) Homo sapiens LL-37 peptide.

Gene expression
Transcription of hph is under control of the Cauliflower mosaic virus 35S promoter and the Agrobacterium tumefaciens nopaline synthase (nos) terminator. Due to the nature of the viral promoter, transcription is expected to occur at high levels.

Transcription of the human LL-37 peptide occurs from the Hordeum vulgare hordein B1 (bHOR) promoter and terminates at the nos terminator. The transcript contains the following (from 5' to 3'): a Zea mays cytokinin dehydrogenase 1 (ZmCKX1sp) signal peptide, a synthetic hexahistidine affinity tag, an E. coli maltose binding protein affinity tag, the LL-37 peptide and a synthetic KDEL ER retention signal. The bHOR promoter restricts expression to the barley endosperm. The synthetic eukaryotic KDEL sequence facilitates the transport of LL-37 peptide to the endoplasmic reticulum. Prior to export from the ER, the translated peptide is cleaved from the peptide. ZmCKX1sp facilitates the transit of LL-37 through the ER and excretion from the cell. The final protein will retain the hexahistidine and maltose binding protein tags for purification.

Note
- Agrobacterium tumefaciens strain AG1 was used in the transformation of barley immature zygotic embryos.
- The bHOR promoter sequence has the following accession number GenBank: X87232.1.
- The final LL-37 peptide is not expected to retain the signal peptides.