Meloidogyne incognita promotes parasitism by lectin-like effector protein

Meloidogyne incognita promotes parasitism by lectin-like effector protein

Meloidogyne incognita relies on lectin-like effector protein to promote parasitism Meloidogyne incognita relies on lectin-like effector protein to promote parasitism

MiCTL1 is expressed in the subventral esophageal glands of Meloidogyne incognita and is secreted into plant tissues during parasitism
.

Photo courtesy of Vegetable Research Institute, Chinese Academy of Agricultural Sciences

MiCTL1 is expressed in the subventral esophageal glands of Meloidogyne incognita and is secreted into plant tissues during parasitism

MiCTL1a interacts with Arabidopsis catalase
.

Photo courtesy of Vegetable Research Institute, Chinese Academy of Agricultural Sciences

MiCTL1a interacts with Arabidopsis catalase

On August 27, the disease team of Xie Bingyan, a researcher from the Plant Protection Research Office of the Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, and the nematode team led by Pierre Abad, a professor at the Sophia Institute of Agricultural Biotechnology, French Academy of Agricultural Sciences, presented in the international journal " New Phytologist " ( New Phytologist).

) Co-published the latest research papers

New Phytologist Meloidogyne incognita

The molecular basis of nematode and plant interaction is the key

The molecular basis of nematode and plant interaction is the key

According to Xie Bingyan, the co-corresponding author of the paper, there are more than 90 species of root-knot nematodes, which can infect more than 5,500 plants and cause economic losses of more than 7 billion U.
S.
dollars each year
.

Among them, Meloidogyne incognita is the most serious type of root knot nematode in agricultural production

"The control of root-knot nematodes mainly includes physical control, biological control and chemical control, but there are disadvantages in field applications such as slow response, low economic benefits, poor control effects and environmental pollution
.

Therefore, the analysis of the molecular interaction between root-knot nematodes and the host The mechanism, to clarify the pathogenic mechanism of root-knot nematodes, can provide an important theoretical basis for finding new targets for the prevention and control of root-knot nematodes and formulating new strategies

At present, planting nematode-resistant crop varieties is the key to solving the problem, but the lack of resistance genes, the commercial application of disease resistance genes are intolerant of high temperature, the disease resistance mechanism is not thorough, and the emergence of toxic groups restrict the development and application of molecular breeding technology.

.

Recent studies have shown that the effector protein expressed by the root-knot nematode esophagus gland plays an important role in the interaction between the nematode and the host
.

Analyzing the function of effector proteins in the parasitic process of nematodes is to reveal the molecular basis of the interaction between nematodes and plants

The key protein lectin in the immune response of nematodes

The key protein lectin in the immune response of nematodes

According to Mao Zhenchuan, the co-corresponding author of the paper and a researcher at the Institute of Plant Protection, lectins are a class of non-immune-derived sugar-binding proteins that are widely found in animals and plants.
They interact with various types of cells and play important biological functions
.

According to protein sequence similarity, lectins can be divided into G, L and C type lectins
.

C-type lectins are widely present in the genus Nematodes, participate in immune regulation and protect the nematodes from infection by pathogens

Caenorhabditis elegans

Nematodes can live on animals and plants
.

In animal parasitic nematodes, C-type lectins are secreted into the host during the parasitic stage, and may regulate the host's immune response

Meloidogyne graminicola

Discover the target protein MiCTL1

Discover the target protein MiCTL1 Discover the target protein MiCTL1 MiCTL1

There are 59 lectin-like proteins in Meloidogyne incognita, but the function of C-type lectin-like effector proteins and their target proteins in plants are still unknown
.

The co-first author of the paper, Dr.
Zhao Jianlong from the Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, introduced that their research proved that the Meloidogyne incognita lectin-like effector protein MiCTL1 is expressed in the subventral esophageal glands and secreted into plant tissues during the parasitic process.
Nematode parasites The initial expression level increased significantly, and it is speculated that it may play an important role in the interaction between nematodes and the host, the establishment of feeding sites, the formation of giant cells, and the regulation of plant immunity
.

The researchers reduced the infectivity of Meloidogyne incognita in Ben's tobacco by inducing the silencing of the MiCTL1 gene
.
The ectopic expression of the MiCTL1 gene in Arabidopsis not only increased the plant's sensitivity to Meloidogyne incognita, but also promoted root growth
.

Yeast two-hybrid and immunoprecipitation experiments showed that MiCTL1a protein interacts with Arabidopsis catalase, which plays an important role in H2O2 homeostasis
.
Knockout or overexpression of catalase showed that the sensitivity of Arabidopsis to Meloidogyne incognita was increased or decreased, respectively
.

In addition, MiCTL1a protein inhibits catalase activity in vivo and in vitro, and also regulates the expression of stress-related genes in Arabidopsis
.

The results of the study indicate that, similar to the cyst nematode, Meloidogyne incognita may regulate host cell hydrogen peroxide homeostasis not only to evade the host immune response, but also to participate in the establishment of feeding sites and the formation and maintenance of giant cells
.

In summary, this study reported for the first time that the lectin effector MiCTL1a of Meloidogyne incognita interacts with the host catalase.
By fine-tuning the redox state of the cell site where the host interacts with Meloidogyne incognita, it helps the nematode and its Establish a parasitic relationship between host plants
.

This research was funded by the National Natural Science Foundation of China, the basic scientific research business expenses of the Chinese Academy of Agricultural Sciences and the innovation project of the Chinese Academy of Agricultural Sciences
.
(Source: China Science News Li Chen)

Related paper information: https://doi.
org/10.
1111/nph.
17690

https://doi.
org/10.
1111/nph.
17690