Genetic stability developed for β-carotene synthesis in BR29 rice line using dihaploid homozygosity

PLoS One. 2014 Jun 17;9(6):e100212. doi: 10.1371/journal.pone.0100212. eCollection 2014.

Abstract

Obtaining transgenic crop lines with stable levels of carotenoids is highly desirable. We addressed this issue by employing the anther culture technique to develop dihaploid lines containing genes involved in β-carotene metabolism. First, we used Agrobacterium- mediated transformation to develop primary transgenic plants containing the β-carotene biosynthetic genes, phytoene synthase (psy) and phytoene desaturase (crtI), which were engineered for expression and accumulation in the endosperm. Transgenic plants were recovered by selecting for the expression of the phosphomannose isomerase (pmi) gene. Dihaploid plants in addition to haploid and tetraploid plant were generated from anther cultures of these primary transgenic plants. In addition to anatomical features of stomata, pollen of different ploidy-plants, molecular analyses confirmed the stable integration of the genes in the anther culture-derived dihaploid plants, and the yellow color of the polished seeds indicated the accumulation of carotenoids in the endosperm. High performance liquid chromatography (HPLC) analysis of the carotenoid extract further confirmed the levels of β-carotene accumulation in the endosperms of the transgenic dihaploid rice seeds.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blotting, Southern
  • Chromatography, High Pressure Liquid
  • Genetic Engineering*
  • Homozygote
  • Mannose-6-Phosphate Isomerase / genetics
  • Mannose-6-Phosphate Isomerase / metabolism*
  • Oryza / genetics*
  • Oryza / growth & development
  • Oryza / metabolism
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Plants, Genetically Modified / genetics*
  • Plants, Genetically Modified / growth & development
  • Plants, Genetically Modified / metabolism
  • Ploidies*
  • RNA, Messenger / genetics
  • Real-Time Polymerase Chain Reaction
  • Reverse Transcriptase Polymerase Chain Reaction
  • Seeds / genetics
  • Seeds / growth & development
  • Seeds / metabolism
  • beta Carotene / biosynthesis*
  • beta Carotene / genetics

Substances

  • Plant Proteins
  • RNA, Messenger
  • beta Carotene
  • Mannose-6-Phosphate Isomerase

Grants and funding

Department of Biotechnology, Govt. of India has provided the financial support. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.