title: Interaction proteins of invertase and invertase inhibitor in cold-stored potato tubers suggested a protein complex underlying post-translational regulation of invertase.
abstract: The activity of vacuolar invertase (VI) is vital to potato cold-induced sweetening (CIS). A post-translational regulation of VI activity has been proposed which involves invertase inhibitor (VIH), but the mechanism for the interaction between VI and VIH has not been fully understood. To identify the potential partners of VI and VIH, two cDNA libraries were respectively constructed from CIS-resistant wild potato species Solanum berthaultii and CIS-sensitive potato cultivar AC035-01 for the yeast two-hybrid analysis. The StvacINV1 (one of the potato VIs) and StInvInh2B (one of the potato VIHs), previously identified to be associated with potato CIS, were used as baits to screen the two libraries. Through positive selection and sequencing, 27 potential target proteins of StvacINV1 and eight of StInvInh2B were clarified. The Kunitz-type protein inhibitors were captured by StvacINV1 in both libraries and the interaction between them was confirmed by bimolecular fluorescence complementation assay in tobacco cells, reinforcing a fundamental interaction between VI and VIH. Notably, a sucrose non-fermenting-1-related protein kinase 1 was captured by both the baits, suggesting that a protein complex could be necessary for fine turning of the invertase activity. The target proteins clarified in present research provide a route to elucidate the mechanism by which the VI activity can be subtly modulated.
authors.affiliation: National Center for Vegetable Improvement (Central China), Wuhan 430070, People's Republic of China; Key Laboratory of Horticultural Plant Biology (Huazhong Agricultural University), Ministry of Education, Wuhan 430070, People's Republic of China; Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Lin
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.forename: Xun
authors.initials: X
authors.lastname: Liu
authors.forename: Yongbin
authors.initials: Y
authors.lastname: Ou
authors.forename: Meng
authors.initials: M
authors.lastname: Li
authors.forename: Huiling
authors.initials: H
authors.lastname: Zhang
authors.forename: Botao
authors.initials: B
authors.lastname: Song
authors.forename: Conghua
authors.initials: C
authors.lastname: Xie
mesh_terms: D015925:Cryopreservation; D018076:DNA, Complementary; D004032:Diet; D004791:Enzyme Inhibitors / Q000378:metabolism*; D061353:Food Storage; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D035281:Plant Tubers / Q000201:enzymology / Q000378:metabolism*; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D011198:Solanum tuberosum / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D013045:Species Specificity; D013395:Sucrose / Q000378:metabolism*; D013649:Taste; D014026:Nicotiana / Q000378:metabolism; D014617:Vacuoles / Q000378:metabolism; D043324:beta-Fructofuranosidase / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism
chemical_list: D018076:DNA, Complementary; D004791:Enzyme Inhibitors; D010940:Plant Proteins; D013395:Sucrose; D011494:Protein Kinases; D043324:beta-Fructofuranosidase
keywords: Cold-induced sweetening; Invertase activity; Post-translational regulation; Potato