Loss of Cytosolic Phosphoglucose Isomerase Affects Carbohydrate Metabolism in Leaves and Is Essential for Fertility of Arabidopsis статья из журнала
Аннотация: Abstract Carbohydrate metabolism in plants is tightly linked to photosynthesis and is essential for energy and carbon skeleton supply of the entire organism. Thus, the hexose phosphate pools of the cytosol and the chloroplast represent important metabolic resources that are maintained through action of phosphoglucose isomerase (PGI) and phosphoglucose mutase interconverting glucose 6-phosphate, fructose 6-phosphate, and glucose 1-phosphate. Here, we investigated the impact of disrupted cytosolic PGI (cPGI) function on plant viability and metabolism. Overexpressing an artificial microRNA targeted against cPGI (amiR-cpgi) resulted in adult plants with vegetative tissue essentially free of cPGI activity. These plants displayed diminished growth compared with the wild type and accumulated excess starch in chloroplasts but maintained low sucrose content in leaves at the end of the night. Moreover, amiR-cpgi plants exhibited increased nonphotochemical chlorophyll a quenching during photosynthesis. In contrast to amiR-cpgi plants, viable transfer DNA insertion mutants disrupted in cPGI function could only be identified as heterozygous individuals. However, homozygous transfer DNA insertion mutants could be isolated among plants ectopically expressing cPGI. Intriguingly, these plants were only fertile when expression was driven by the ubiquitin10 promoter but sterile when the seed-specific unknown seed protein promoter or the Cauliflower mosaic virus 35S promoter were employed. These data show that metabolism is apparently able to compensate for missing cPGI activity in adult amiR-cpgi plants and indicate an essential function for cPGI in plant reproduction. Moreover, our data suggest a feedback regulation in amiR-cpgi plants that fine-tunes cytosolic sucrose metabolism with plastidic starch turnover.
Год издания: 2014
Авторы: Hans‐Henning Kunz, Shirin Zamani-Nour, Robert Hausler, Katja Ludewig, Julian I. Schroeder, Irina Malinova, Joerg Fettke, Ulf‐Ingo Flügge, Markus Gierth
Издательство: Oxford University Press
Источник: PLANT PHYSIOLOGY
Ключевые слова: Plant nutrient uptake and metabolism, Plant Molecular Biology Research, Photosynthetic Processes and Mechanisms
Другие ссылки: PLANT PHYSIOLOGY (PDF)
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PubMed Central (HTML)
PubMed (HTML)
PLANT PHYSIOLOGY (HTML)
PubMed Central (HTML)
PubMed (HTML)
Открытый доступ: hybrid
Том: 166
Выпуск: 2
Страницы: 753–765