Understanding the Molecular Processes of Tuberous Roots

Gene expression

Understanding the molecular processes of tuberous root formation will help in breeding, plant evolution, and medicinal care. This study identified a number of genes that play important roles in root tuberous development. In particular, genes related to cell development and membrane activities were particularly enriched in root cortex tissues. Moreover, genes that regulate plant metabolism and transport were found to be highly expressed in tuberous roots.

The differentially expressed genes were identified in the tuberous roots of ZZ P and XL Y plants. A heat map of differentially expressed structural genes and TFs in the anthocyanin biosynthesis pathway was produced.

Regulation of energy metabolism

This study reveals that two gene families play a key role in the regulation of energy metabolism by tuberous roots. Both genes are involved in the expansion of the roots and starch and sucrose metabolism. Both of these pathways are essential for continued development and tuberous root formation. To gain an understanding of the roles of these genes, a gene-trait relationship was conducted.

The two gene families differ in the proportion of TFs involved in energy metabolism. One group contains genes related to anthocyanin biosynthesis. In the next step, these genes will be investigated for their regulatory roles in sweet potato.

Regulation of signal transduction

The regulation of signal transduction is critical for the development and formation of tuberous roots. Various 'omics' data have shed new light on the mechanisms involved in this process. In particular, light regulation plays a key role in tuberous root formation. Several genes involved in sucrose and starch metabolism are involved in tuberous root formation.

Many of these genes are transcribed in leaves and transported to roots. For example, stBEL5 mRNA in potato was transported through phloem and promoted the formation of storage organs. Moreover, 14 BELs genes were consistently upregulated during the tuberous root expansion stage. In addition, the regulatory network for tuber development appears to be similar in sweet potatoes.