Walking barefoot through the grass or hiking through the woods can invoke a feeling of calm, and a peaceful happiness. It can trigger nostalgic memories, and make us feel connected to nature, and the various life forms around us. Needless to say, being in close proximity to plant life makes us feel interlinked with the world around us. The question then arises of if these organisms are capable of reciprocating the feeling, do they know we are there and if so, how does the environment impact their gene expression?
This article will seek to explore 7 mind-bending facts about plant epigenetics, scientific phenomenon that suggest that plants are not as static as they appear to be.
1. The plant epigenome is surprisingly similar to the mammalian epigenome
Plant epigenomes are actually very similar to mammalian epigenomes in that they both regulate gene expression by modifying histones and by methylation of DNA. However, they differ from mammals in that plants are much more sensitive to their environments, and are much more prone to undergo epigenetic modifications because of their surroundings. They also differ in that in plants, methylation is mostly restricted to non-coding regions, while in mammals it also occurs in the coding regions of DNA .
2. Studying plant epigenetics could lead to higher yield, higher quality crops
One of the most significant ways that studying plant epigenetic can potentially be very beneficial is through crop improvement. Scientists have been able to study what environmental stressors cause epigenetic modifications that result in better crop yields, and higher quality fruits and vegetables. Theoretically, we could use this knowledge to improve our crop yield and quality everywhere .
3. Plants have an epigenetic memory that allows them to remember environmental stress
Another interesting facet that has arisen from plant epigenetics is that plants have the ability to remember stressors that they encounter in the environment, and are thus better equipped to survive the next time they come across that stressor. This process is known as “priming” and can be seen in events such as droughts, or periods of heavy heat. Plants that have experienced such phenomena as a drought are much better equipped to handle it again in the future because of the epigenetic memory they have acquired from surviving a previous drought .
4. Plants can defend themselves from other plants by releasing epigenetic chemicals into the soil
Even more fascinating is the fact that plants can defend themselves from other nearby plants via epigenetic mechanisms. The way they do this is by releasing chemicals into the soil that will later be converted in histone deacetylase inhibitors. These inhibitors are then uptaken by nearby “enemy” plants, where they will disrupt their epigenetic profiles, thus disrupting normal growth and function .
5. Plants are better than animals at transmitting epigenetic information to their children
The DNA methylation marks in plants are transmitted to their offspring in a manner that has been described as “much more direct than in animals.” This is because plants do not undergo the genome-wide wave of demethylation in germ cells that animals do. The results of this are that the offspring of plants will be epigenetically more similar to their parents than the offspring of animals .
6. Epigenetic memory can regulate and control flowering time
Appropriate regulation of flowering time is essential for the reproductive success of a plant and the viability of its offspring. Plants must rely on the ability to recognize a long period of cold temperature in order to properly flower and reproduce. Though the precise epigenetic mechanism of how plants remember this period of cold is debated, it is undoubtable that epigenetic enzymes control flowering time through modifications such as methylation and acetylation of DNA and Histones .
7. Plants, like animals, rely on hormones to regulate gene expression
Similar to animals, plants use a complex system of hormone signals and receptors in order to allow cells within the organism to talk to one another. Plants have developed an extremely complex system of listening to signals from neighboring cells, and integrating them into their environment. The ability of the plant to understand and integrate these neighboring signals can be very dependent on the epigenetic state or memory of the cell. Research in this field is constantly expanding and we are always learning new things about this very complex process .