Scientists from the University of California – Riverside (UCR) have successfully decoded the signals plants send themselves to initiate photosynthesis, the process through which plants convert sunlight into sugars for sustenance. The resulting study, “Anterograde signaling controls plastic transcription via sigma factors separately from nuclear photosynthesis genes,” was published in Nature Communications.
Botanists have known for decades that the nucleus of each plant cell sends the command, in the form of proteins, to initiate photosynthesis. But these are far from the only proteins that nuclei manipulate. “Our challenge was that the nucleus encodes hundreds of proteins containing building blocks for the smaller organelles,” said UCR botany professor Meng Chen “Determining which ones are the signal to them to trigger photosynthesis was like finding needles in a haystack.”
This new study is built off previous research done by Chen’s team in which they demonstrated that certain proteins are activated by exposure to light, starting photosynthesis. The four newly documented proteins are all involved with that reaction; they signal small organs to convert into chloroplasts that generate the sugars.
The National Institutes of Health funded this study as it may prove useful in the development of a cure for cancer. According to the news release, this hope is “based on similarities between chloroplasts in plant cells and mitochondria in human cells. Both organelles generate fuel for growth, and both harbor genetic material.” Thanks to past research, we know about communications sent from organelles back to the nucleus, but we know very little about signals originating with the nucleus. “The nucleus may control the expression of mitochondrial and chloroplast genes in a similar fashion. So, the principles we learn from the nucleus-to-chloroplast communication pathway might further our understanding of how the nucleus regulates mitochondrial genes and their dysfunction in cancer,” Chen said.
This research may also prove useful in creating extraterrestrial indoor farms, a key step in allowing humanity to live on other planets.