Month: March 2024

A group from Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery, Faculty of Medicine, University of Tsukuba, Japan, etc. has reported about changes in glycosylation in Pancreatic Ductal Adenocarcinoma mediated by KRAS gene mutations.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10963106/

It was shown that Fucosilation and mannosylation were upregurated in pancreatin ductal adenocarcinoma with KRAS gene mutations.
The lectins enriched in KRAS mutants included fucose-binding lectins (AAL, rAAL, AOL, rAOL, rRSIIL, and UEAI) and mannose-binding lectins (rRSL, rBC2LCA, rPAIIL, and NPA).

Glycans are said to be the face of cells, and the glycosylation on the cell surface changes depending on the tissue and desease state.
As a result, the glycosylation of exosomes released from cells drags the glycosylation of the cell surface, but for some reason, expression of sialic acid tends to be very strong.
For example, there is a paper written by Shimoda and Akiyoshi at. al., Kyoto University (see below).
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6687741/
Why is this?
There is a paper that says it may be aimed at masking the immune system (in Japanese), but is that true?
for example,
https://www.jstage.jst.go.jp/article/dds/38/4/38_270/_pdf
In contrast, the authors cited above suggest that it is involved in the uptake of exosomes via Siglecs on the cell surface.
https://www.sciencedirect.com/science/article/abs/pii/S0006291X17314845?via%3Dihub

（cited from the above listed paper）

A group from State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China, etc. has reported about how to induce “cry for help” response to assemble disease suppressing and growth promoting rhizomicrobiome.
https://www.nature.com/articles/s41467-024-46254-3

The well-studied model pathogen Pseudomonas syringae pv. tomato (Pst) DC3000 and its nonpathogenic derivatives (D36E, D36EFLC and D36EHPM) were used in this experiment using Arabidopsis as a model plant.

Treatment with either DC3000 or the derivatives increased the relative contents of long chain organic acids (LCOAs) and amino acids in root exudates. The bacterial phyla Proteobacteria (32.1%–38.3%) and Actinobacteria (15.4%–20.7%) were the most abundant groups in the rhizosphere, and the genus Devosia (belonging to phylum Proteobacteria) was enriched in the D36E and D36EFLC treatments. Interestingly, the abundance of genus Devosia was negatively correlated with L-malic acid and myristic acid in root exudates but positively correlated with 4-hydroxypyridine.

Finally, it was shown that the metabolites of D36E and D36EFLC alone are sufficient to induce a “cry for help” response. So, this study demonstrates the ability of nonpathogenic strains and their MAMPs to act as elicitors to induce the formation of a disease-suppressive soil legacy, which can potentially support agricultural applications.