Biological Sciences Seminar
Dr. Dongjie Zhao
Postdoctoral Scholar, Biological Sciences
Michigan Tech University
Visualization of electrical signals and their propagations in different plants
Electrical activity plays an important role in response to environmental cues in plants. In particular, electrical responses can participate the reception of various actions such as biotic stress, respiration, water uptake, leaf movement, mechanical stimuli, and biological clock. Interestingly, the electrical activity can propagate from one place to another at single-, multi-cellular, and tissue/organ levels in both plants and animals. However, unlike animals, plants lack nerve system. My talk will try to address what routes and how plants convey their electrical signals in response to environmental cues.
To investigate how electrical signals in different plant responses to the mechanical stimulation or other type of stress, we compared the propagation patterns of electrical activities between Venus flytrap and sunflower using a combined approach of plant leaf surface potential recording, multi-electrode array recording, optical recording and single cell-derived protoplast patch clamp recording. We found distinct electric transmissions in plants that the Venus flytrap specialized leaf, termed lobe, has a much faster and identical propagation speed of action potential from the mechanic stimulation center to all directions. In contrast, such propagations in sunflower upon stress stimulation are slow and uneven in various transmission directions along the leaf surface. Traditionally, the plant vascular system, especially the phloem region, is considered to be the major route for plant long-distance electric signal transmission, which might be the case in sunflower. Similar observation was also made from Arabidopsis under stress. But flytrap has a specialized leaf for fast action in catching its prey insects, and may use different mechanism to transmit its electric signal in the leaf. My data showed that the action potential signal transmission within a single flytrap leaf may be through the cellular junctions, i.e. plasmodesmata.
Thursday, November 16 at 3:00 am to 4:00 am
Electrical Energy Resources Center (EERC), 229
1400 Townsend Drive, Houghton, MI 49931