High-level production of lactostatin, a hypocholesterolemic peptide, in transgenic rice using soybean A1aB1b as carrier

Transgenic Res. 2013 Jun;22(3):621-9. doi: 10.1007/s11248-012-9672-5. Epub 2012 Nov 6.

Abstract

Hypercholesterolemia, a form of cardiovascular disease, is one of the leading causes of deaths worldwide. Lactostatin (Ile-Ile-Ala-Glu-Lys), derived from β-lactoglobulin in cow's milk, is a bioactive peptide with hypocholesterolemic activity higher than sitosterol, a known anti-hypercholesterolemic drug. Here, we successfully developed a transgenic rice accumulating a much higher level of lactostatin by inserting 29 IIAEK sequences into the structurally flexible (nonconserved) regions of soybean seed storage protein, A1aB1b, and introducing it into LGC-1 (low glutelin content mutant 1) as host variety. A1aB1b containing 29 lactostatins was expressed in the endosperm of rice seed cells by using seed specific promoters and sorted into novel compartments distinct from normal PB-I (ER-derived protein body) and PB-II (protein storage vacuoles). Transgenic rice seeds accumulated approximately 2 mg of lactostatins/g of dry seeds, which is relatively high compared with previous reports. Our findings suggest that the introduction of a high copy number of bioactive peptide into seed storage proteins as carrier is one of the effective means in producing higher amounts of bioactive peptides in rice.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Endosperm / genetics
  • Endosperm / metabolism
  • Genetic Vectors
  • Microscopy, Immunoelectron
  • Molecular Sequence Data
  • Oligopeptides / biosynthesis*
  • Oligopeptides / genetics
  • Oryza / genetics*
  • Oryza / metabolism
  • Plants, Genetically Modified / genetics*
  • Plants, Genetically Modified / metabolism
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Seed Storage Proteins / genetics
  • Seed Storage Proteins / metabolism
  • Solubility
  • Soybean Proteins / genetics*
  • Soybean Proteins / metabolism
  • Soybeans / genetics*

Substances

  • Oligopeptides
  • Recombinant Proteins
  • Seed Storage Proteins
  • Soybean Proteins
  • lactostatin