3.9 C
Oxford
Thursday, April 9, 2020
Home Articles When the going gets tough….. the organelles get going

When the going gets tough….. the organelles get going

Chloroplasts, the tiny photosynthetic energy factories of plant cells, were observed to move in response to light and temperature as long as a century ago. Within a cell, these organelles can migrate towards the cell wall closest to a light source, thereby optimising photosynthesis. They do, however, move away from very strong light, presumably to escape photodamage. In low temperature conditions, chloroplasts move away from the cell wall closest to the outside world. This temperature response is less well understood than the response to light, and a recent Plant, Cell and Environment study revisited these experiments on the liverwort, Marchantia polymorpha (pictured), and also looked at the mobility of other organelles induced by low temperatures.

Marchantia polymorph
The liverwort Marchantia polymorph. Photograph by Cathy Shields.

In cold conditions, chloroplasts move, within the cell where they find themselves, towards the centre of the plant. This movement appears to be mediated by actin filaments, which are positioned at the “front” of the chloroplast (in terms of its direction of movement). Although not completely understood, the movement of chloroplasts in response to cold has been seen in evergreen but not in deciduous ferns. This suggests that it may play a role in the cold resistance mechanisms of plants. Intriguingly, plant cell nuclei have also been observed to migrate away from bright light. This could be explained as an avoidance mechanism against ultraviolet DNA damage. M. polymorpha nuclei also move towards the centre of the plant in cold temperatures. The authors speculate that this could represent a migration to a slightly warmer intracellular environment, where the activity of DNA-repairing enzymes would be less impaired.

New techniques provide us with opportunities to better understand both the mechanisms and reasons underlying organelle migration in response to environmental conditions, and the authors suggest several potential lines of further research.

Reference

Ogasawara Y., Ishizaki K., Kohchi T. & Kodama Y. (2013). Cold-induced organelle relocation in the liverwort Marchantia polymorpha L., Plant, cell & environment, DOI:

Image

The liverwort Marchantia polymorph. Photograph by Cathy Shields.

Cathy Shields
Cathy Shields is a Research Assistant at The University of Edinburgh, currently working on a project gauging the efficacy of an online learning tool used on undergraduate Biological Sciences courses. Her scientific research background is in the impacts of air pollution on plants.

Latest Articles

Most Popular

10 Plants Used to Spice up Sex

It's well-known that plants can affect how the brain works. Take the right plant in the right dose and you can have an altered...

Amazing moss and how to identify it

If I told you that during a 200m walk down a suburban London street I saw 13 different species from one group of organisms,...

Adapted to kill: How the pitcher plant traps its prey

When it comes to carnivorous plants it's Venus Flytraps that get the most attention, with their snapping jaws. Bladderworts have stunningly fast traps. Sundews...

The cell biology of secondary cell wall biosynthesis

What is it that makes a plant get up and stay up? A new review looks at the creation of secondary cell walls. These microscopic features are the key to understanding the architecture of the plants we see around us.

Recent Comments

>