Plant roots are highly flexible to high salinity. However, the molecular mechanism by which root developmental flexibility is regulated is unknown. Previous studies have reported that the miR172c and NNC1 gene relationship plays a key role in soybean-rhizobial symbiosis. Since the miR172c promoter contains several stress-related elements, miR172c may have a role in root response to abiotic stress. Zulfiqar Ali Sahito and Lixiang Wang of Huazhong Agricultural University in China studied miR172c to determine the mechanism of root developmental flexibility.
Researchers found that miR172c is greatly induced by salt stress in soybean (Glycine max). Overexpression of miR172c increased the soybean roots' sensitivity to salt stress. In contrast, knockdown of miR172c activity resulted in reduced root sensitivity to salt stress.
Furthermore, the target gene of miR172c, NNC1 (Nodule Number Control 1), was downregulated by salt stress. The transgenic roots with overexpressed or knocked-down NNC1 expression also exhibited the altered root sensitivity to salt stress.
This study reveals the crucial role of miR172c-NNC1 module in root stress tolerance to salt stress in soybean.
[bmcplantbiol.biomedcentral.com]