Bitter Orange PtrA/NINV Gene Confers Tolerance to Multiple Abiotic Stresses

Alkaline/neutral invertase (A/N-INV) is an enzyme that hydrolyzes sucrose irreversibly into glucose and fructose and is essential for normal plant growth, development, and stress tolerance. However, the mechanism supporting its role in abiotic stress tolerance has not yet fully studied. The team from Huazhong Agricultural University in China, led by Bachar Dahro, isolated and characterized an A/N-INV gene (PtrA/NINV) from bitter orange (Poncirus trifoliate), a cold-hardy relative of citrus.

PtrA/NINV expression levels were found to be induced by cold, salt, dehydration, sucrose, and ABA, but decreased by glucose. It was also found to be localized in both chloroplasts and mitochondria. Overexpression of PtrA/NINV resulted in higher A/N-INV activity and greater reducing sugar content under normal and stress conditions. This also conferred enhanced tolerance to multiple stresses, including cold, high salinity, and drought.

PtrA/NINV is an important gene implicated in sucrose decomposition, and plays a positive role in abiotic stress tolerance. Thus, PtrA/NINV has a great potential to be used in transgenic breeding for improvement of stress tolerance.

For more information, read the full article on BMC Plant Biology.