Horizontal gene transfer: used by parasitic plants (Introduction)

by David Turell , Sunday, October 30, 2016, 13:48 (2946 days ago) @ David Turell

This is not the usual event, since the plants are highly complex as compared to HGT in bacteria:

https://www.sciencedaily.com/releases/2016/10/161024170709.htm

:In a study, researchers detected 52 incidents of the nonsexual transfer of DNA -- known as horizontal gene transfer, or HGT -- from a host plant that later became functional into members of a parasitic plant family known as the broomrapes, said Claude dePamphilis, professor of biology, Penn State. The transferred genes then became functional in the parasitic species. Although considered rare in more plants and other complex species, like plants, HGT may thus occur in some parasitic plants.

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"While horizontal gene transfers in less complex species, such as bacteria, is are common, most evolution in more complex organisms is driven by the sexual exchange of DNA, along with mutation and natural selection. However, the researchers suggest that the close feeding connections of parasitic plants with their hosts may increase the chances of intact genes traveling from the host to the parasite's genome where it can quickly become functional.

"'Parasitic plants seem to have a far greater rate of horizontal gene transfer than non-parasitic plants and we think this is because of their very intimate connection they have with their host," said dePamphilis.

"The roots of the parasite contact and enter the host, and then begin extracting water, sugars, mineral nutrients and even nucleic acids, including DNA and RNA, he added.

"'So, they are stealing genes from their host plants, incorporating them into the genome and then turning those genes back around, very often, as a weapon against the host," said dePamphilis.

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"The researchers focused on transcriptomes -- expressed gene sequences -- of three parasitic plants:,

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" Because the researchers considered mRNA, which can move between hosts and their parasites, as a possible source of the transfers, they tested and re-tested the data to rule out the experimental host as the source of the genetic material. Instead, they found that the foreign sequences had been derived from entire genes of past host plants and incorporated into the parasitic plants genomes."

Comment: It is becoming apparent that HGT is present all through various branches of life. Remember even human genomes show elements of various viruses. This is one of the inventive mechanisms used in advancing evolution. Knowing it happens does not tell us how it is allowed to happen. The mechanisms need to be discovered. Did God do it? By this I mean is it such a highly complex mechanism that chance evolutionary development is unlikely and therefore agency or saltation is required.