Journal Article

The GORKY glycoalkaloid transporter is indispensable for preventing tomato bitterness

Zemach, Itay, Zamir, Dani, Aharoni, Asaph, Crocoll, Christoph, Ben-Dor, Shifra, Lambertz, Sophie Konstanze, Nour-Eldin, Hussam Hassan, Shani, Eilon, Bocobza, Samuel, Kanstrup, Christa, Panda, Sayantan, Vainer, Andrii, Dong, Yonghui, Veres, Dorottya, Michaeli, Simon, Kazachkova, Yana, Hu, Yangjie, Rogachev, Ilana

2021

Overview

Fruit taste is determined by sugars, acids and in some species, bitter chemicals. Attraction of seed-dispersing organisms in nature and breeding for consumer preferences requires reduced fruit bitterness. A key metabolic shift during ripening prevents tomato fruit bitterness by eliminating α -tomatine, a renowned defence-associated Solanum alkaloid. Here, we combined fine mapping with information from 150 resequenced genomes and genotyping a 650-tomato core collection to identify nine bitter-tasting accessions including the ‘high tomatine’ Peruvian landraces reported in the literature. These ‘bitter’ accessions contain a deletion in GORKY, a nitrate/peptide family transporter mediating α -tomatine subcellular localization during fruit ripening. GORKY exports α -tomatine and its derivatives from the vacuole to the cytosol and this facilitates the conversion of the entire α -tomatine pool to non-bitter forms, rendering the fruit palatable. Hence, GORKY activity was a notable innovation in the process of tomato fruit domestication and breeding. Bitterness is one of the fruit traits that are most disliked by consumers. In this study, the authors identified and characterized a tonoplast membrane transporter in tomato fruit, which is responsible for the translocation of bitter α-tomatine and other derivatives from the vacuole to the cytoplasm for non-bitter conversion.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 38 / 38/22 / 38/77 / 631/449/1659 / 631/449/2667 / 82 / 82/58 / Biomedical and Life Sciences / Bitter taste / Bitterness / Breeding / Conversion / Cytoplasm / Cytosol / Domestication / Fruit - chemistry / Fruit - genetics / Fruits / Gene mapping / Genomes / Genotyping / Glycoalkaloids / Humans / Life Sciences / Localization / Plant Breeding / Plant Proteins - genetics / Plant Proteins - metabolism / Plant Sciences / Ripening / Solanum lycopersicum - chemistry / Solanum lycopersicum - genetics / Solanum lycopersicum - metabolism / Sugar / Taste / Tomatine / Tomatoes / Translocation