Laasya and Parth win poster award

Congratulations to Laasya and Parth for winning a poster award at the 2018 NCBS Annual talks! The poster described how mistranslation seems to influence the bacterial stress response, focusing on initiator tRNA mutants.

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New paper: Experimental evolution of insect immune memory

Our new paper describing Imroze and Arun’s massive experiment with thousands of infected beetles was recently published online. Within about 10 generations of exposure to Bacillus thuringiensis, flour beetles evolved divergent immune responses: either improved but generalized immune resistance, or specific immune priming (memory). We think that the divergent response is driven by the frequency of exposure to the pathogen. However, for replicate populations within a given exposure treatment, we found a very high degree of parallelism. This is the first report of evolved immune memory in insects, and we are very excited to now figure out the underlying mechanisms. Read the NCBS news article about this work here, or read the paper.

Update, 24 June 2018: The Hindu covered our work in an article; check it out!

Winter conference season

This winter is packed with exciting meetings! Here’s the menu:

Pratibha and I just returned from a fantastic SMBE satellite meeting in Kaziranga, Assam. Congratulations to Pratibha for getting a travel grant to present her work! The meeting brought together a bunch of people working on microbial evolution in natural and experimental populations. There was lively discussion on a wide range of topics in microbial evolution, good food, and of course, Rhinos. Big thanks to the key organizers, Siddartha Sankar Satapathy and Edward Feil!

Vrinda and I are now off to IISER Pune for a Conference on Evolutionary and Integrative Biology. The speaker lineup includes many seasoned and new evolutionary biologists across India, so we are looking forward to an exciting meeting.

Soon after this, the whole lab (and our campus) will participate in the 2018 NCBS Annual Talks. Mrudula, Rittik, Laasya, and Gaurav Agavekar will each present posters about their work; and Gaurav Diwan will present a short talk.

Finally, to conclude this conference season I will speak at an Indo-French workshop on Evolutionary Developmental and Cell biology (EVODECE) at the Observatoire Oceanologique de Banyuls sur Mer in France. The meeting is funded by CEFIPRA and DST, and features a very diverse collection of evolutionary and cell biologists from India and France.

Do come talk to us if you spot us at any of these events!

Gaurav describes new ant species

While collecting ants for his MSc thesis project on ant communities in the Andaman Islands, Gaurav Agavekar found two species of ants from the genus Tetramorium that turned out to be new to science. Along with Evan Economo’s lab at OIST Japan, he recently described these species in a paper in PeerJ. The new species – T. krishnani and T. jarawa – are named in honor of the late Prof KS Krishnan (NCBS), and the indigenous Jarawa people of the Andaman Islands. Read more about the work here.

Update, Feb 2018: Gaurav’s work is covered in an article on Mongabay India.

Aparna wins award at SPEEC-Up 2017

SPEEC-Up 2017 was the first iteration of what we hope will be an annual 3-minute talk competition for students of ecology, evolution and conservation in Bangalore. The event was a lot of fun, and a great way to get introduced to a wide range of work from our neighbours. I am truly happy to have had a chance to listen to so many cool talks.

We had three competitors from the lab- Kruttika, Aparna and Rittik all gave great talks about their respective work with insect gut microbes. We’re very happy that Aparna won a runner-up prize for her talk on beetle gut microbes! Here she is, accepting her award (with joint winner Vignesh).

Aparna_SpeecUp

Open postdoctoral position

I am recruiting a postdoctoral fellow to analyze bacterial communities associated with flour beetles. The postdoctoral fellow will work with a team of researchers towards the following goals:

  • Quantify the repeatability of ecological and evolutionary changes in the gut microbiome of an insect adapting to a new diet
  • Determine the metabolic and genetic basis of the microbiome changes
  • Test the importance of inter-species associations in driving microbiome changes

The position is fully funded through a grant from the Wellcome Trust-DBT India Alliance, and will begin from January 2018 for a maximum of 5 years.

  • A background in evolutionary biology, ecology, or microbiology is essential
  • Experience with handling anaerobic microbes would be beneficial
  • Experience with coding or mathematical modeling would be beneficial
  • The ability and motivation to think and work independently is important

To apply, please write to me with the following details:

  • Your CV
  • A short paragraph (~300 words) summarizing your research interests and career goals
  • Contact information for 2 people who can write a letter of recommendation for you
  • A 1-page summary of any paper from our lab. Include your criticisms and any questions that arise from the work

Summer travel

The conference season is suddenly upon us! The lab will be out in full force this year since many of the first people to join the lab have cool results to report. Everyone has received various competitive grants to help support their travel, which is superb news! We are all looking forward to good feedback and hearing about the latest in evolutionary biology from across the world. Do come and chat if you spot us.

Kruttika and Aparna are off to the Evolution meeting in Portland, Oregon. Aparna is supported by a DST travel grant.

Mrudula, Saurabh, Gaurav and I will be at the SMBE meeting in Austin, Texas. Mrudula has a DBT travel grant, Gaurav has a DST travel grant, and Saurabh has a CSIR travel fellowship.

After SMBE, Mrudula and I will hop over to the GRC on Microbial Population Biology in New Hampshire.

Meanwhile, Saurabh will spend some time visiting labs in Boston and then attend the MBL Workshop on Molecular Evolution at Woods Hole. Saurabh has received funding support from MBL as well as CSIR.

In August, Mrudula, Gaurav and Saurabh will join me in Barcelona, Spain, to teach in the School of Molecular and Theoretical Biology.

Finally, to wrap up the summer: Aparna, Kruttika and I will participate in the ESEB meeting in Groningen, Netherlands. Aparna has received an ESEB travel award to attend this meeting.

New paper on the evolutionary implications of stress-induced mutations

Recently I wrote a Primer (a short tutorial/introduction for a subject of broad interest) to accompany a new paper in PLoS Biology demonstrating stress-specific mutation spectra in E. coli (Maharjan and Ferenci 2017). Stress-induced mutagenesis (SIM) is a fascinating phenomenon, whereby some organisms show a transient increase in mutation rates when exposed to stresses such as starvation. However, the evolutionary implications of this phenomenon have been controversial, and I give a brief introduction to this debate (and potential ways forward) in my Primer. In their paper, Maharjan and Ferenci show that not all stresses induce mutagensis, but each stress produces a unique distribution of mutational types. These results suggest that stress-specific mutation spectra may influence evolutionary trajectories in a stress-specific manner. This remains to be explicitly tested, but we are now a little bit closer to understanding the evolutionary consequences of SIM.

The Primer and the related paper are available online, if you would like to know more.

On insect-bacterial associations

Aparna, Kruttika and I recently wrote a short review article on insect bacterial associations, that was featured in the March 2017 newsletter of the Indian Society of Cell Biology. We’d like to share it here since it might be of general interest. Enjoy!

A PARTNERSHIP STORY: INSECT-BACTERIAL ASSOCIATIONS

Aparna Agarwal, Kruttika Phalnikar and Deepa Agashe

National Centre for Biological Sciences (NCBS), Bangalore

The world around us is full of microbes that influence both biotic and abiotic components of ecosystems. For instance, nitrogen-fixing bacteria enrich the soil1, and algae in marine ecosystems provide sustenance to a variety of organisms2,3. On the other hand, pathogenic bacteria cause diseases across trophic levels, changing the environment around them dramatically. Such interactions have been extensively studied for a long period of time. However, non-pathogenic host-bacterial associations also influence host physiology and even host behaviour4,5. For example, in mice, differences in gut bacterial communities determine utilization of specific dietary components and the propensity for diseases like obesity and diabetes6,7. Gut bacteria are also linked to several neurological disorders such as depression and anxiety8. Such dependence of animal hosts on their gut microbes is not limited to humans, but extends across the tree of life.

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