Recently, Huang Binquan’s team at the Germplasm Bank of Wild Species in Yunnan University published a research paper in New Phytologist, revealing a new regulatory mechanism controlling potato tuber formation. They discovered a transcription factor named StbHLH93 that promotes stolon-to-tuber transition by modulating TIC56 gene and thus mediating proplastid-to-amyloplast conversion.

 

Potato is the third most important food crop globally. Tuber is the key organ determining its yield. Through transcriptomic analysis, Huang’s team found StbHLH93 specifically expressed in the apex of potato stolons and tubers. Downregulating StbHLH93 inhibited stolon swelling and tuber development, while overexpressing it promoted stolon-to-tuber transition and increased yield.

 

This study reveals the important role of amyloplast development during tuber formation, expanding our understanding of the regulatory mechanism of potato tuber formation. It also provides new insights into potato genetic improvement.