The primary in vivo steroidal alkaloid glucosyltransferase from potato

K.F. McCue, P.V. Allen, L.V.T. Shepherd, A. Blake, J.L. Whitworth, M.M. Maccree, D.R. Rockhold, D. Stewart, H.V. Davies, W.R. Belknap

    Research output: Contribution to journalArticlepeer-review

    69 Citations (Scopus)


    To provide tools for breeders to control the steroidal glycoalkaloid (SGA) pathway in potato, we have investigated the steroidal alkaloid glycosyltransferase (Sgt) gene family. The committed step in the SGA pathway is the glycosylation of solanidine by either UDP-glucose or UDP-galactose leading to a-chaconine or a-solanine, respectively. The Sgt2 gene was identified by deduced protein sequence homology to the previously identified Sgt1 gene. SGT1 has glucosyltransferase activity in vitro, but in vivo serves as the UDP-galactose:solanidine galactosyltransferase. Two alleles of the Sgt2 gene were isolated and its function was established with antisense transgenic lines and in vitro assays of recombinant protein. In tubers of transgenic potato (Solanum tuberosum) cvs. Lenape and Desirée expressing an antisense Sgt2 gene construct, accumulation of a-solanine was increased and a-chaconine was reduced. Studies with recombinant SGT2 protein purified from yeast show that SGT2 glycosylation activity is highly specific for UDP-glucose as a sugar donor. This data establishes the function of the gene product (SGT2), as the primary UDP-glucose:solanidine glucosyltransferase in vivo.

    © 2006 Elsevier
    Original languageEnglish
    Pages (from-to)1590-1597
    Number of pages8
    Issue number15
    Publication statusPublished - Aug 2006


    • solanum tuberosum
    • Solanaceae
    • potato
    • molecular genetics
    • steroidal glycoalkaloids
    • UDP-glucose
    • solanidine
    • glucosyltransferase
    • chaconine
    • solanine
    • Sgt1
    • Sgt2


    Dive into the research topics of 'The primary in vivo steroidal alkaloid glucosyltransferase from potato'. Together they form a unique fingerprint.

    Cite this