Differential expression involved in starch synthesis pathway genes reveal various starch characteristics of seed and rhizome in lotus (Nelumbo Nucifera)

Abstract

Lotus (Nelumbo nucifera) is one of the main aquatic vegetables in China. Its seed and rhizome are main edible parts which are rich in starch. Preliminary experiments of starch contents revealed that seed and rhizome expressed great differences in amylose and amylopectin contents. The rhizomes have higher amylopectin content, while the seeds have higher amylose content. In this study, we have estimated 16 varieties of lotus seeds and found that the amylose content of lotus seeds ranged from 30% to 50%, with an average amylose content of 43%, which showed high‐amylose content characteristics. Morphological analysis of lotus seed shown that starch rapid accumulated in 20 DAF (day after fertilization) ∼ 26 DAF. Transcriptome of lotus seeds indicated that starch genes played an important role in seed development. Especially in 22 DAF, the genes which controlled amylose synthesis significantly increased, in contrast, the expression of amylopectin‐related genes was stable and might limit the synthesis of amylopectin. We further analyzed the expression patterns of 11 key related genes between lotus seeds and rhizomes, and found that the expression of amylose‐related genes to were higher in lotus seed, while the expression of genes related to amylopectin synthesis were higher in rhizome. This study provided a comprehensive research of molecular basis for starch in lotus seed and rhizome. Different expression among key genes during starch accumulation might be the principal cause of the differences in starch properties between seed and rhizome. Practical Application Differential expression involved in starch synthesis pathway genes is the main reason for various starch characteristics of seed and rhizome in lotus. High amylose content in lotus seed is a valuable trait for developing functional food.

Identifying high‐risk factors and mitigation strategies for acrylamide formation in air‐fried lotus root chips: Impact of cooking parameters, including temperature, time, presoaking, and seasoning

“…Lotus root is an underwater rhizome with a unique, compact texture, and it is rich in essential nutrients (Yi et al., 2022; Zhu et al., 2022). In our preliminary investigation, which aimed to find out which food ingredients are more likely to produce acrylamide during cooking, it was found that lotus root stands out with exceptionally high levels of acrylamide production.…”

Research overview on the genetic mechanism underlying the biosynthesis of polysaccharide in tuber plants

“…ADP-Glucose is then converted by ADP glucose pyrophosphorylase (AGPase) into hexose phosphate (G1P and G6P), leading to further ADP-glucose synthesis ( Fig. 2 ) ( Zhu et al, 2022 ). Finally, ADP-glucose produces amylopectin through the activities of starch isomerase, starch branching enzyme, and soluble starch synthase, while another portion is transformed into amylose by granule-bound starch synthase and stored in endosperm cells ( Lee et al, 2022 ).…”