Biosynthesis of antinutritional alkaloids in solanaceous crops is mediated by clustered genes

M Itkin, U Heinig, O Tzfadia, A J Bhide, B Shinde, P D Cardenas, S E Bocobza, T Unger, S Malitsky, R Finkers, Y Tikunov, A Bovy, Y Chikate, P Singh, I Rogachev, J Beekwilder, A P Giri, A Aharoni

Research output: Contribution to journalArticle

Abstract

Steroidal glycoalkaloids (SGAs) such as α-solanine found in solanaceous food plants--as, for example, potato--are antinutritional factors for humans. Comparative coexpression analysis between tomato and potato coupled with chemical profiling revealed an array of 10 genes that partake in SGA biosynthesis. We discovered that six of them exist as a cluster on chromosome 7, whereas an additional two are adjacent in a duplicated genomic region on chromosome 12. Following systematic functional analysis, we suggest a revised SGA biosynthetic pathway starting from cholesterol up to the tetrasaccharide moiety linked to the tomato SGA aglycone. Silencing GLYCOALKALOID METABOLISM 4 prevented accumulation of SGAs in potato tubers and tomato fruit. This may provide a means for removal of unsafe, antinutritional substances present in these widely used food crops.

Original languageEnglish
JournalScience
Volume341
Issue number6142
Pages (from-to)175-9
Number of pages5
ISSN0036-8075
DOIs
Publication statusPublished - 12-Jul-2013

Keywords

  • Crops, Agricultural/genetics
  • Gene Expression Profiling
  • Gene Expression Regulation, Plant
  • Gene Silencing
  • Genes, Plant
  • Lycopersicon esculentum/genetics
  • Multigene Family
  • Nutritive Value/genetics
  • Solanaceous Alkaloids/biosynthesis
  • Solanum tuberosum/genetics

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