Chinese Researchers Identify Key Gene for High Protein Content in Maize

Chinese scientists have successfully isolated a key gene from teosinte, the wild ancestor of modern corn, that dramatically increases the protein content in maize seeds. Published in the journal Nature, the research was led by the Chinese Academy of Sciences (CAS), along with Shanghai Normal University and Sichuan Agricultural University. The discovery provides a powerful genetic tool to reverse a historical trend: over 9,000 years of domestication, modern corn varieties lost crucial ancestral genes, resulting in lower protein levels that make livestock industries heavily reliant on imported soybean meal.

The researchers identified the specific gene as Teosinte high protein 3 (THP3-T), which controls an enzyme central to how the plant processes nitrogen into protein. Over centuries of selective breeding for higher grain yields, this beneficial gene was inadvertently weeded out, leaving it present in just 2.1% of modern maize lines. By studying its mechanics, the team discovered that natural variations in this ancestral gene optimize the plant's nutrient transport, allowing it to pack far more protein into its seeds.

To test the real-world impact, the scientists bred this rediscovered gene alongside another previously found high-protein gene into Zhengdan958, one of China's most widely grown commercial corn hybrids. The results were striking: the protein content of the corn seeds jumped from 8.5% to as high as 13%, and the overall protein of the entire plant increased without sacrificing any crop yield. This genetic pairing offers a highly promising strategy for breeding premium, high-protein crops to help meet rising global demand for food and livestock feed.

For more details, read the research news in the CAS Newsroom.