Overexpression of IbSnRK1 enhances nitrogen uptake and carbon assimilation in transgenic sweetpotato

Abstract

Nitrogen is an important nutrient for plant development. Nitrogen and carbon metabolisms are tightly linked to physiological functions in plants. In this study, we found that the IbSnRK1 gene was induced by Ca(NO 3) 2. Its overexpression enhanced nitrogen uptake and carbon assimilation in transgenic sweetpotato. After Ca(15 NO 3) 2 treatment, the 15 N atom excess, 15 N and total N content and nitrogen uptake efficiency (NUE) were significantly increased in the roots, stems and leaves of transgenic plants compared with wild type (WT) and empty vector control (VC). After Ca(NO 3) 2 treatment, the increased nitrate N content, nitrate reductase (NR) activity, free amino acid content, and soluble protein content were found in the roots or leaves of transgenic plants. The photosynthesis and carbon assimilation were enhanced. These results suggest that the IbSnRK1 gene plays important roles in nitrogen uptake and carbon assimilation of sweetpotato. This gene has the potential to be used for improving the yield and quality of sweetpotato.

A sucrose non‐fermenting‐1‐related protein kinase‐1 gene, IbSnRK1, improves starch content, composition, granule size, degree of crystallinity and gelatinization in transgenic sweet potato

“…In our previous study, one IbSnRK1 gene was isolated from sweet potato cv. Lushu 3 (Jiang et al ., ), and its overexpression increased the nitrate N content in roots and soluble protein and starch contents in leaves of transgenic sweet potato (Ren et al ., ). In this study, we found that its overexpression not only increased starch content, but also decreased proportion of amylose, enlarged granule size and improved degree of crystallinity and gelatinization in the storage roots of transgenic sweet potato.…”

Engineering Properties of Sweet Potato Starch for Industrial Applications by Biotechnological Techniques including Genome Editing

“…High nitrogen application leads to reduced root yield in both nitrogen-tolerant and nitrogen-susceptible sweet potato varieties. Nitrogen-tolerant varieties show more carbon allocation in tuberous roots under no-nitrogen conditions compared with nitrogensusceptible varieties [68]. These results indicate that nitrogen regulates carbon flux through mechanisms that are yet to be determined, and a balance between nitrogen and carbon metabolism is required during sweet potato root development.…”

PpSnRK1α overexpression alters the response to light and affects photosynthesis and carbon metabolism in tomato

“…Overexpression of IbSnRK1 in sweet potato increased the assimilation of nitrogen and carbon and improved starch content and quality (Jiang et al, 2013;Ren et al, 2018;Ren et al, 2019). AGPase can convert glucose-1-phosphate (Glc-1-P) into ADP-glucose, which is crucial in the first step of starch synthesis.…”