Skip to main content
. 2021 Jan 21;11:2034. doi: 10.1038/s41598-021-81598-6

Figure 7.

Figure 7

Proposed model for nodulation signaling and modulation by Bradryhizobium elkanii type III effector Bel2-5. A soybean root-derived genistein induces the production of Nod factors (NFs) in B. elkanii. Recognition of NFs by NF receptors triggers a signaling cascade leading to nodulation. The genistein also induces B. elkanii to inject effector proteins into soybean cells. NopL suppress plant defense responses by modulating the MAPK cascade. The ErnA effector triggers nodule organogenesis by a yet unknown mechanism. Bel2-5 effector likely interferes with the nodulation signaling pathway at least at two levels: (1) by modulating cytokinin biosynthesis-related genes that promoting nodule organogenesis and (2) by repressing ethylene biosynthesis-related genes and host-dependent defence responses that are deleterious to the bacterial infection. It should be noted that these DEGs may contain secondary and tertiary indirect effects as well as Bel2-5 direct effects.