Transcriptomic changes in donor soybean, dodder bridge, and the connected recipient soybean induced by cadmium addition

Hangkai Pan Li Zhou Junmin Li ^*

• Taizhou University, Taizhou, China

Background: Cuscuta spp. (dodders) are parasitic plants that belong to the Convolvulaceae family. In nature, dodder often forms a bridge-like connection between two or more host plants like, which is known as a dodder bridge. Cadmium (Cd 2+ ) is an important heavy metal ion that affects plant growth. However, it remains unclear whether Cd 2+ treatment can directly or indirectly induce transcriptomic changes in plants through dodder bridge.Results: In this study, a pot experiment was conducted to investigate the effects of Cd 2+ treatment on donor plant and neighboring recipient plant connected by dodder bridge. Transcriptome analysis revealed that Cd 2+ treatment significantly affected the expression of genes involved in the 'Plantpathogen interaction', 'phenylpropanoid biosynthesis', and 'isoflavonoid biosynthesis' pathways in both donor and recipient plants at 2, 12, 24, and 48 h. Cd 2+ indirectly induced changes in the dodder bridge, which included processes related to oxidation-reduction ('oxidation-reduction process', 'oxidoreductase activity', and 'regulation of transcription') and Ca 2+ signaling pathways ('Plantpathogen interaction', 'MAPK signaling pathway', 'AMPK signaling pathway', 'mTOR signaling pathway'). Additionally, mRNA transfer was observed from soybean to dodder. mRNA, Ca 2+ and ROS might play crucial roles in the signal transduction process induced by Cd 2+ stress.Cd 2+ treatment could directly and indirectly induce transcriptomic changes in the donor plant and neighboring recipient plant connected by dodder bridge. These results contribute to a better understanding of how plants connected by dodder bridges respond to environmental stresses.