A mucin-like protein of planthopper is required for feeding and induces immunity response in plants.

5 years ago

A mucin-like protein of planthopper is required for feeding and induces immunity response in plants.

Guangcun He, Dazhao Yu, Liang Hu, Xinxin Shangguan, Shengli Jing, Weiwei Rao, Zhizheng Wang, Yan Zhao, Lili Zhu, Rongzhi Chen, Yan Wu, Jianping Guo, Wei Guan, Jing Zhang, Yinhua Ma, Bingfang Liu, Bo Du, Huiying Wang

The brown planthopper, Nilaparvata lugens (Stål), is a pest that threatens rice production worldwide. While feeding on rice plants, planthoppers secrete saliva, which plays crucial roles in nutrient ingestion and modulating plant defense responses, although the specific functions of salivary proteins remain largely unknown. We identified a N. lugens-secreted mucin-like protein (NlMLP) by transcriptome and proteome analyses and characterized its function, both in brown planthopper and in plants. NlMLP is highly expressed in salivary glands and is secreted into rice during feeding. Inhibition of NlMLP expression in planthoppers disturbs the formation of salivary sheaths, thereby reducing their performance. In plants, NlMLP induces cell death, the expression of defense-related genes, and callose deposition. These defense responses are related to Ca2+ mobilization and the MEK2 MAP kinase and JA signaling pathways. The active region of NlMLP that elicits plant responses is located in its C-terminus. Our work provides a detailed characterization of a salivary protein from a piercing-sucking insect other than aphids. Our findings that the protein that functions in plant immune responses offer new insights into the mechanism underlying interactions between plants and herbivorous insects.

Publisher URL: http://doi.org/10.1104/pp.17.00755

DOI: 10.1104/pp.17.00755