C-terminal frameshift mutations generate viable knockout mutants with developmental defects for three essential protein kinases

This study is led by Professor Kabin Xie (Institute of Huazhong Agricultural University College of Plant Science and Technology, Wuhan, China).

Loss-of-function mutants are basic resources for gene function researches. Over the past decade, CRISPR/Cas9 genome editing has become a routine genetic tool for targeted gene knockouts. However, it’s difficult for some important genes to generate viable and heritable knockout mutants. Protein kinases are fundamental components of intracellular signal transduction. The deletion of these genes can lead to severe growth, developmental defects and sterility in the plants. Therefore, it is very important to obtain heritable knockout mutants of these genes in analyzing the signaling networks of plant growth, development and stress immunity.

In their previous research, the authors found that knocking out rice mitogen-activated protein kinases 1 (OsMPK1) failed to generate viable and inherited mutants. Also, the authors reported that at least 20 knockout mutants of the RLK/RLCK genes displayed developments defects and failed to generate viable seeds.

In this study, the authors successfully obtained several weak mutants by targeting C-terminal sequence of embryo-lethal gene OsMPK1. These weak mutants showed severe developmental defects and enhanced disease resistance to Magnaporthe oryzae and generated tens of viable seeds that inherited the mutations. Also, the authors generated viable and heritable mutants for a wall-associated protein kinase (Os07g0493200) and a leucine-rich repeat receptor-like protein kinase (Os01g0239700), while the null mutations of these genes were lethal. In conclusion, this work demonstrates that the introduction of frameshift mutations near the C-terminal sequences can decrease the activity of these protein kinase, provide valuable resources for gene function studies and facilitate the regulation of protein kinase activity in signaling networks which control rice development, immunity, and abiotic stress tolerance.

See the article:

C-terminal frameshift mutations generate viable knockout mutants with developmental defects for three essential protein kinases

https://link.springer.com/article/10.1007/s42994-024-00165-5