👀 Whitefly:- Path to the first know horizontal gene transfer between plants and insects!

[Ichha]

I observed a fly on my phyllantus plant that may have caused the infection. What pest was it??Is it aphids??..It was later found out in chaatshalala that the fly is a white fly!

https://agritech.tnau.ac.in/crop_protection/crop_prot_crop_insect_medi_Keela.html

Whitefly

@Himanshu shared a reference that hinted towards a very recent study (2020-2021) of the very first horizontal gene transfer between plants and insects!

An insect pest acquires multiple plant genes

This is the original paper shared by @Theertha
https://www.researchgate.net/publication/350394774_Whitefly_hijacks_a_plant_detoxification_gene_that_neutralizes_plant_toxins#:~:text=Whitefly%20hijacks%20a%20plant%20detoxification%20gene%20that%20neutralizes%20plant%20toxins,-April%202021

Chaatshalala discussion 19/10/22

We started with discussion horizontal gene from phyllantus plant to white fly ( Bemisia tabaci ) that was mentioned in the reference sent by @Himanshu

#There are two methods of gene transfer as told by @Chitralekha

• horizontal gene transfer - between offspring ( transduction, translation and conjugation)
• vertical gene transfer - between parent to offspring eg meiosis

@shreya said Horizontal gene transfer of bacteria occur in bacteria contain f plasmid and bacteria containing no plasmid. Two cells connect by a bridge from which the plasmid are transferred

So how does horizontal gene transfer occur in plants ? Do plants have plasmid ?

According to the references sent my understanding was that plant produces toxic chemicals (sec metabolite) coded by gene “x”
and has another gene"y" that codes for something that protects plant from its toxic chemicals

Acc to ref sent by @Theertha

Ideally The toxins should have affected and killed whiteflies

However it was found that the white fly acquired gene ( BtPMaT1) from the plant, that protects plant from its own toxin, thereby making whitefly resistant to the toxins produced by plant

What is BtPMaT1?

•Gene BtPMaT1 in plants produces an enzyme , phenolic glucosidemalonyltransferase , that transfers a Malonyl group on compounds ,including phenolic glycosides (secondary metabolite),required for its normal metabolic activities.

•The whitefly acquired the gene through horizontal gene transfer and is use it to transfer malonyl group to phenolic glycosides which they are toxic to.

•Malonylated phenolic glycosides are not toxic to the fly. Hence the insect (whitefly)is now resistant to the secondary metabolite

How does the gene transfer ? Does that happen directly or via bacteria/viruses? Does evolution play any role?

[Himanshu]

Nice summary @Ichha @Theertha @khushi_goel
Now there are two questions upfront let’s find answers for the following…
1 How we are sure that the gene responsible for detoxification was transfered from a plant to whitefly?
Can’t this be an Atavism (the reappearance in an individual of characteristics of some remote ancestor that have been absent in intervening generations)

2. How can this information be utilized to develop pest control strategies against B. tabahi ?

Please find answers for these two points and demonstrate the scientific evidences answering these queries

@Ichha @Theertha and others

[kvk (Vinod Kumar K)]

1. Multicellular organisms need not own all in their body from their genetics. The ‘gene responsible for detoxification’ need not be of the whitefly but of a microbiota in the whitefly.

2. The Human Microbiome Project of the US NIH ‘tested how changes in the human microbiome are associated with human health or disease’. Other attempts to weaken pathogenic microbiota or strengthen symbiotic or commensal microbiota are active. Plant ecological space consisting of the microbiota too is a new research area. “In 2015 the American Phytopathological Society (APS) launched a research framework, the Phytobiomes Initiative, to facilitate the organization of research into phytobiome. As part of this effort, in 2016 it launched Phytobiomes Journal , an open-access journal.”

Discussion on 19/10/2022 questions “How does the gene transfer ? Does that happen directly or via bacteria/viruses?” . Answer based on microbiota is via bacteria/viruses.

A wonderful picture of the whitefly shows the gene in the gut cells. The gut is the favourite ecospace of microbiota. Yesterday my friend Vijayaraman told me about a 17 Nov 2022 Nature paper “Intermittent Fasting protects against Alzheimer’s disease … through remodeling of the gut microbiota.”