Dionne

About Us       Protocols &c.       Lab Members       Publications       Contact       Links

Welcome to the Dionne lab!

That is to say, Marc Dionne's lab, at Imperial College London; not to be confused with any other Dionne lab.

We are interested in the ways in which host genotype affects the biology of bacterial infection. Drosophila melanogaster is our animal model of choice.

Work in the lab has been funded by the Biotechnology and Biological Sciences Research Council, the Wellcome Trust, and the Medical Research Council.

A BBSRC-funded postdoctoral position is available in the lab! If you're interested, get in touch, or apply here!

Metabolic-immune interaction and host genetics in infection

It has been known for centuries that chronic infections cause systemic metabolic disruption, but it is fundamentally unclear why and how these events are linked. Does metabolic disruption somehow facilitate the host response to infection? If so, how? We address these fundamental biological questions by analyzing pathogenic infections and their consequences in the fruit-fly Drosophila melanogaster. We use classical Drosophila genetics, computational analysis and modeling of gene expression, biochemistry, and intravital microscopy to probe the metabolic-immune interface.

One pathogen of particular interest to us is Mycobacterium marinum. We have previously shown that flies infected with M. marinum exhibit progressive loss of metabolic stores accompanied by mild hyperglycemia. We have shown that these effects are caused, in part, by systemic disruption of signaling via the anabolic effector kinases Akt and p70 S6 kinase. The transcription factor MEF2 responds to nutrient signals to regulate expression of both immune effectors and anabolic enzymes. Remarkably, though MEF2 promotes the expression of both groups of genes, its choice of targets is regulated by a conserved phosphorylation that alters its affinity for the TATA binding protein. It appears that the disruption of anabolic kinase activity may be required to permit MEF2 to drive the antibacterial response. This work has recently been published in Cell.

Ongoing work continues to explore other metabolic inputs into MEF2, other targets of MEF2 in its two discrete physiological states, and the pathways by which infection disrupts anabolic kinase activity.

Cytokines and cytokine signalling

In the course of screening for mutants with defective responses to M. marinum, we find a lot of molecules and pathways that end up being involved in cytokine signalling and its consequences. Cytokines regulate the realized immune response of the fly, much as they do in mammals; they also can be significant direct drivers of pathology due to effects on immune and nonimmune target tissues. However, very little is known about the biology of cytokines in Drosophila melanogaster, especially in the context of bacterial infections.

Some time back, we showed that two different TGF-betas regulate fly immunity, each inhibiting a specific arm of the immune response, and each being produced by only a subset of phagocytes. Check it out!

We've also done some exciting work in collaboration with Frederic Geissmann's lab on the role of JAK-STAT signalling in flies on a high-fat diet; you can read about it here. We continue to work on the roles of this pathway in Mycobacterium marinum infection and in muscle physiology—we hope to be able to say more about these soon.

<wikionly>

Recent updates to the lab wiki

List of abbreviations:

N

This edit created a new page (also see list of new pages)

m

This is a minor edit

b

This edit was performed by a bot

(±123)

The page size changed by this number of bytes

28 January 2022

			N    09:45		Dropbase: VASA generator‎‎ 7 changes history +646‎ [Florian Hollfelder‎ (7×)]
					09:45 (cur | prev) −83‎ Florian Hollfelder talk contribs
					09:44 (cur | prev) +5‎ Florian Hollfelder talk contribs
					09:44 (cur | prev) +6‎ Florian Hollfelder talk contribs
					09:43 (cur | prev) +165‎ Florian Hollfelder talk contribs
					09:41 (cur | prev) 0‎ Florian Hollfelder talk contribs
					09:41 (cur | prev) 0‎ Florian Hollfelder talk contribs
			N		09:32 (cur | prev) +553‎ Florian Hollfelder talk contribs Created page with "{{DropBase}} Category:Protocol Category:Microfluidics <div ...> =Overview= 100px|left '''Description''' • 3 aqueous inlets flow-focusing junction <br> • The example shown has a 80 μm wide junction<br><br> '''Reference''' F. Salmen et al. 'Droplet-based single-cell total RNA-seq reveals differential non-coding expression and splicing patterns during mouse development', biorxiv. 2021,(https://www.biorxiv.org/content..."

			03:17		Lee:JC‎‎ 2 changes history +46‎ [Wooin Lee‎ (2×)]
					03:17 (cur | prev) +46‎ Wooin Lee talk contribs →‎2022
					03:16 (cur | prev) 0‎ Wooin Lee talk contribs →‎Schedule

			N    02:59		Dropbase: 3-pL-droplets-01‎‎ 2 changes history +1,223‎ [Florian Hollfelder‎ (2×)]
					02:59 (cur | prev) −6‎ Florian Hollfelder talk contribs
			N		02:57 (cur | prev) +1,229‎ Florian Hollfelder talk contribs Created page with "{{DropBase}} Category:Protocol Category:Microfluidics <div ...> =Overview= 180px|left '''Description''' • Dual aqueous inlet flow-focusing junction for the generation of ≈ 3 pL droplets. BLue: depth ≈ 12 µm <br> '''Reference''' D. Schnettler Fernández, O. J. Klein, T. S. Kaminski, P.-Y. Colin, F. Hollfelder. Ultrahigh-throughput directed evolution of a metal-free α/β-hydrolase with a Cys-His-Asp triad into an efficient..."

			N    02:58		DropBase:droplet electrosorting 4‎‎ 5 changes history +4,204‎ [Florian Hollfelder‎ (5×)]
					02:58 (cur | prev) 0‎ Florian Hollfelder talk contribs
					02:35 (cur | prev) −42‎ Florian Hollfelder talk contribs
					02:26 (cur | prev) +1,621‎ Florian Hollfelder talk contribs
					02:03 (cur | prev) 0‎ Florian Hollfelder talk contribs
			N		01:40 (cur | prev) +2,625‎ Florian Hollfelder talk contribs Created page with "{{DropBase}} Category:Protocol Category:Microfluidics <div ...> =Overview= 180px|left '''Description''' Microfluidic chip device fluorescence-activated droplet sorting (FADS) of ≈ 3 pL-sized droplets (offline-incubation). Blue: silanised area for emulsion handling, depth: 21.5–23 μm. Red: signal electrode (-). Black: ground electrode (+). <br> '''Reference''' D. Schnettler Fernández, O. J. Klein, T. S. Kami..."

			N    02:57		DropBase:droplet electrosorting 5‎‎ 2 changes history +4,354‎ [Florian Hollfelder‎ (2×)]
					02:57 (cur | prev) 0‎ Florian Hollfelder talk contribs
			N		02:42 (cur | prev) +4,354‎ Florian Hollfelder talk contribs Created page with "{{DropBase}} Category:Protocol Category:Microfluidics <div ...> =Overview= 250px|left '''Description''' Integrated microfluidic chip device for droplet generation, incubation and fluorescence-activated droplet sorting (FADS) of ≈ 11 pL-sized droplets (in-line incubation). Incubation time in the delay line is ≈ 20–30 min. This long design is suitable to measure the reaction progress in droplets to estimate the..."

02:46

DropBase:droplet generation 3 inlets‎ diffhist +275‎ Florian Hollfelder talk contribs

01:11

DropBase:Contact‎ diffhist +168‎ Florian Hollfelder talk contribs

27 January 2022

18:54

User creation log User account Lboudreau talk contribs was created by Yar talk contribs and password was sent by email ‎

09:36

Chenlab:Publications‎ diffhist −4‎ Kaifu Chen talk contribs

05:28

X-Lab‎ diffhist +23‎ ChanEngr talk contribs

26 January 2022

			12:09		CAMRI:SeminarSeries‎‎ 3 changes history +216‎ [Lacey Berry‎ (3×)]
					12:09 (cur | prev) +1‎ Lacey Berry talk contribs
					12:09 (cur | prev) +13‎ Lacey Berry talk contribs
					12:08 (cur | prev) +202‎ Lacey Berry talk contribs

</wikionly>

<nonwikionly> This page was created using Open Wetware.</nonwikionly>