Researchers Use CRISPR to Identify Tobacco Gene Regulating Leaf Senescence

Experts from ​​Chongqing University of Posts and Telecommunications, Chinese Academy of Agricultural Sciences, and China Tobacco Guangxi Industry Co. Ltd. discovered that a gene called NtBAG5 plays a crucial role in promoting leaf senescence (leaf aging) in tobacco plants. Using CRISPR-Cas9 gene-editing technology, the team found that disabling this gene delayed leaf yellowing and improved antioxidant activity.

The study found that NtBAG5 works closely with calmodulin (CaM), and when calcium levels change, the interaction between NtBAG5 and CaM adjusts, which affects the plant's antioxidant system and triggers senescence. The researchers also revealed that hormones, such as ABA and ethylene, increased NtBAG5 activity, while methyl jasmonate suppressed it, showing that leaf aging is controlled by a complex mix of hormones and calcium signals.

The research team concluded that NtBAG5 is a central regulator of leaf senescence in tobacco. By integrating signals from calcium ions and plant hormones, the NtBAG5-CaM complex weakens the antioxidant defense system, which leads to ROS accumulation and leaf senescence. The study provided new insights into how plants age and offers potential strategies to delay senescence and improve crop quality.

For more information, read the study from GM Crops & Food.