This fascinating parasitic plant, found lurking in clusters at the base of trees, has optimized its survival strategy so well that it was able to prune nearly a third of its genome.
genus known as glans foreskin, you might mistake it for a strange, fleshy pink fungus that protrudes almost phallicly from fallen leaves.with a stimulating scent Something like carnal corruptionparasites are far from plants.
However, what looks like a mushroom cap is actually a flower head whose roots are tightly intertwined with the roots of the tree lurking beneath, creating a successful parasitic relationship. Balanophora swallow nutrients from other organisms.
A team of scientists led by geneticist Xiaoli Chen from China’s BGI Research found that “rather than prolonging growth, haustorial chamber Like other plant parasites, they invade their hosts and steal nutrients. Balanophora mix that flesh with the host’s vascular system underground With tuber-like organs. This organ is a chimeric structure, containing a mix of host and parasite genetic material.
In addition, Balanophora‘s genome reduction is extreme even for a parasite; Sapria: another, but very different, genus of parasitic plants. This is an interesting example of convergent evolution, where very different organisms independently develop very similar traits over time.
“Similar but independent extents of gene loss Balanophora and Sapria It’s impressive.” Chen says. “It shows that there is very strong convergence in the genetic evolution of holoparasitic lineages, despite their apparently different life histories and appearances, and despite having evolved from different groups of photosynthetic plants. ing.”
Parasites are really amazing. Their survival strategy is to find other species that are doing well and benefit them in various ways. This can also be beneficial to the host. And it’s a great engine of evolution.
But when you take life from another living being, you don’t necessarily need all the biological functions you started with before turning to a life of crime. Many plant parasites have evolved to become highly dependent on their hosts, and their genomes have shrunk accordingly.
something like a parasite Balanophora and Sapria mandatory or holoparasite, and is completely dependent on the host. Both have even lost the ability to photosynthesize, which is how green plants obtain nutrients.
Chen wanted to know how these plants got to their current form, so he decided to take a closer look at their genomes.
This was instantly cool…and weird. Sapria This is a fairly extreme example of a holoparasite. Over time, we lose 38 percent of our genome.but Balanophora It’s not far. It has lost a pretty amazing 28 percent of its genome.
Even more surprising, both parasites have lost a similar set of genes. Obtaining nutrients from the host means that genes involved in photosynthesis are no longer needed. The two parasites also carry genes related to metabolism. Some means of dealing with stolen nutrients is still needed.
Interestingly, the researchers found that both plants have lost the gene for synthesizing abscisic acid, a hormone that plants use for signal transduction and stress responses.But on the other hand Baronophora Although abscisic acid cannot be produced, it can be used for signal transduction. This suggests that they may have lost genes that overlap with host functions so as not to harm the host.
![](https://www.sciencealert.com/images/2023/09/sapria-flower.jpg)
“Most of the lost genes are Balanophora It is probably related to a function that is essential for green plants but is functionally dispensable for parasites. ” botanist Sean Graham says from the University of British Columbia.
“That said, there are probably instances where the loss of a gene was actually beneficial, rather than simply reflecting a loss of function. Loss of the entire abscisic acid biosynthesis pathway may be a good example. It may help them maintain physiological synchronization with the organism.” This needs to be tested in the future. ”
This means that some gene loss in the parasite is an adaptation to the parasite’s lifestyle, rather than simply a loss of unnecessary function. This is an interesting discovery that could help us better understand how parasitic and symbiotic relationships between organisms evolve.
The research team believes that other holoparasitic plants may exhibit similar characteristics, which could be useful for studying not only parasite-host relationships, but also how plants communicate with each other. It suggests that there is.
“Study of parasitic plants advances our understanding of the dramatic changes in genomes and the complex interactions between parasitic plants and their hosts.” says geneticist Juan Liu. BGI Research.
“Genomic data provide valuable insight into the evolutionary and genetic mechanisms behind the dependence of parasitic plants on their hosts, and how parasitic plants manipulate host plants to survive.”
This study natural plants.