Bio 2

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What plants have immune systems too? How cool. Listen to this short podcast about my work on plant immunity in the Academic Minute.

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Back in the day I was born and raised in the Bavarian (or better Franconia) countryside. I went to school in two world heritage cities, Bamberg and Regensburg. ///Sometimes I really miss these skewed old stone buildings and clean rivers. /// In these early days are rooted my still highly influential punk-rock and left wing politics views. I was heavily involved in anti-facist and fun loving politics. One of the great adventures was the yearly organization of a DIY youth music festival called Jahninselfest, which is still going strong. With a fellowship for Gifted People by the State of Bavaria in the bag I moved to Leipzig to study Biochemistry at the local University. During my second year I started to get interested in plants. Even now it still amazes me how plants are able to convert light energy into matter via photosynthesis. We humans rely on this process so heavily every second we breath. For my third year I went to the University of Glasgow to do an Erasmus year at a University abroad. Because of a serendipitous email I figured that Glasgow offered an excellent Plant Science course, talked with the amazing course co-ordiantor Peter Dominy, changed courses and stayed in Glasgow. The following two years I enjoyed outstanding plant science education with a tiny course size of six students. Studying as it should be supported by a Gatsby Plant Science Undergraduate Stipendship.  For my final year Honors project I worked with Lucio Conti on the involvement of small ubiquitin-related modifiers (SUMO) in regulating salt stress response in the model plant Arabidopsis [1]. To this day I am absolutely thankful to have been mentored by such a meticulous, no frills, no bollocks scientist.

For my PhD I decided to move on. After several rejections from Universities across the Atlantic I ended up doing a rotation PhD at the John Innes Center (JIC) and The Sainsbury Laboratory (TSL). In hindsight this was the best possible outcome for me as the JIC and TSL are offering state of the art facilities and a world-famous intellectual environment. Within my rotation year I first worked with Jonathan Jones/ Cyril Zipfel on the perception system of the model plant Arabidopsis for bacterial pathogen associated molecular patterns (PAMPs) [2,3].  For the second rotation, I moved on to work on a mutant in Medicago truncatula impaired in establishing symbioses with mycrorrhizae fungi [4] in the lab of Giles Oldroyd. In my final rotation, I joined Sophien Kamoun’s Lab and worked with the vanguard Joe Win on annotating proteases in the newly sequenced genome of the oomycete plant pathogen Phytophtera infestans [5]. At the end of my rotation year I decided to join the brand new group of Cyril Zipfel at the TSL. I think what won me over was the highly dynamic environment of the TSL, the new and exciting topic of PAMP triggered immunity in plants and the prospect of working in Tokyo, Japan, in Ken Shirasu’s lab for a couple of month.  During my three year PhD project at the TSL I studied the regulation of plant immune receptor kinases that recognize conserved molecules of pathogens (PAMPs) at the plasma membrane. Many of these immune receptor kinases (e.g. FLS2 and EFR) require co-regulatory receptor-like kinase (RLKs) (e.g. SERK3/BAK1) to initiate full signaling [6-9].  Some of these RLKs are shared with other hormone signaling pathways. In this respect I demonstrated that the mechanistic regulation of immune receptor kinases by BAK1 can be uncoupled from BAK1’s requirement to function in hormone signaling pathway. Henceforth immune receptor kinases are regulated by differential phosphorylation involving BAK1 [7]. My PhD project started off with an elegant forward genetic screen of which the most-interesting mutant, bak1-5, was carrying a mutation in the known very well studied gene BAK1. /// I still remember when a senior post-doc in David Bauclombe‘s lab congratulated me on the map-based cloning of my first gene and I just thought: ‘ Are you kidding. It’s bloody BAK1, which function has been shown previously and everybody is working on. ‘ /// Two+ years later and multiple hours spend in the cold room and hot lab doing biochemistry it turned out all fine [7].  All the hard work also paid off and let to some ‘fame’ as my ‘classmate’ Lucy Foulston and me were awarded with the John Innes Foundation Prize for Excellence in Scientific Research.

For my first post-doc I decided to finally make the big step across the pond (see also the blog entry about this adventure here). I decided it would be awesome to work on an actual crop plant and live in a warm pleasant climate.  Under this premises I decided to join Pam Ronald lab in sunny California at UC Davis working on immune receptor kinase signaling in rice. My post-doc project revolves around the immune receptor kinase XA21 that mediates a strong resistance response against the bacterial pathogen Xanthomonas oryzae pv. oryzae.  In particular, I am interested in the molecular mechanism regulating the kinase and biological activity of immune receptor kinases such as XA21 that belong to the non-arginine-aspartate (non-RD) kinase subclass [10,11]. /// Is there a molecular mechanism that makes non-RD kinases more ‘suitable’ for initiating innate immune signalling across kingdoms? /// For this project I am very lucky and utterly grateful to have secured my own funding initially supported by an EMBO long-term fellowship and currently by a Human Frontier Science Program long-term fellowship. These fellowships enabled me to pursue, develop and raise my own research direction and intellectual opinion. Without them I for sure would not be where I am now.  As a side project I am also interested in the bacterial molecule that triggers XA21 mediated immunity, which is most likely a small peptide sulfated by the tyrosine sulfo-transferase RaxST [12].

Well the major project of my post-doc didn’t really pan out as planned. A good high risk project. Nonetheless in the three+ years I spend working in and with the Ronald’s lab I learned an tremendous amount about science, reproducibility and how to recover from huge setbacks. By now you can read about much of my work in well-respected scientific journals [14, 16, 19-22]. For example, I showed that the XA21 immune receptor in rice requires the coreceptor kinase OsSERK2 (but not OsSERK1) for initiation of disease resistance [16]. We were also able to improve rice immunity to economically  important bacterial pathogen by genetically transferring an immune receptor (EFR) from Arabidopsis [21]. However the immune boost was unfortunately not as strong as hoped for. In an interesting site project we tested and confirmed our capabilities to analyze subproteomes of non-model plant species such as the potential bioenergy crop switchgrass [20].

I wasn’t only doing science at UC Davis. For many years I was an active representative of our local post-doc union UAW5810. Our union represents over 6000 post-doc employees at the University of California. Being a post-doc is mostly a rewarding profession yet for sure  working and living conditions can be markedly improved. In order to spread the word we published an article in e-Life describing the positive impact UAW5810 has in CA and far beyond <– must read [18].

By now (05/2015) I moved on to new frontiers (highlighted by NatureJobs #ScientistOnTheMove). I am currently working at the Research School of Biology, Australian National University, Canberra, Australia. For my work on stripe rust on wheat I hold an independent DECRA fellowship from the Australian Research Council. The Discovery Early Career Award gives me the financial support and freedom to develop my own research project under guidance of senior faculty, Prof. John Rathjen. The coming years I will study how the economically important fungal pathogen stripe rust evolves on an big island such as Australia. So stay tuned! I hope you will once again be able to read about recent scientific advances on well respected pre-print servers and in peer-reviewed journals.

 

Outside the lab you can often find me in the pool, at a local open water swim event, hiking in my backyard watching kangaroos with family or simply enjoying nature in beautiful South-east Australia.

Benjamin

Email: benjamin.schwessinger@anu.edu.au

twitter @schwessinger

 

Publication list:

 
22. Schwessinger B*, Bart R, Krasileva KV, Coaker G*. Focus issue on plant immunity: from model systems to crop species. Front Plant Sci. 2015;6:195.
* Corresponding Authors

21. Schwessinger B*, Bahar O*, Thomas N, Holton N, Nekrasov V, Ruan D, et al. Transgenic Expression of the Dicotyledonous Pattern Recognition Receptor EFR in Rice Leads to Ligand-Dependent Activation of Defense Responses. PLoS Pathog. 2015 Mar 30;11(3):e1004809.
* These authors contributed equally to the work

20. Lao J, Sharma MK, Sharma R, Fernández-Niño SMG, Schmutz J,… Schwessinger B*. Proteome profile of the endomembrane of developing coleoptiles from switchgrass (Panicum virgatum). Proteomics. 2015 Mar 1; in press
* Corresponding Author

19. Zuo S, Zhou X, Chen M, Zhang S, Schwessinger B, Ruan D, et al. OsSERK1 regulates rice development but not immunity to Xanthomonas oryzae pv. oryzae or Magnaporthe oryzae. J Integr Plant Biol. Dec 1;56(12):1179–92.

18. Cain B, Budke JM, Wood KJ, Sweeney NT, Schwessinger B*. How postdocs benefit from building a union. eLife Sciences. 2014 Nov 21;3:e05614.
* Corresponding Author

17. Macho AP*, Schwessinger B*, Ntoukakis V*, Brutus A, Segonzac C, Roy S, et al. A Bacterial Tyrosine Phosphatase Inhibits Plant Pattern Recognition Receptor Activation. Science. 2014 Mar 28;343(6178):1509–12.
* These authors contributed equally to the work

16. Chen X*, Zuo S*, Schwessinger B*, Chern M, Canlas PE, Ruan D, et al. An XA21-Associated Kinase (OsSERK2) Regulates Immunity Mediated by the XA21 and XA3 Immune Receptors. Mol Plant. 2014 May;7(5):874-92.
* These authors contributed equally to the work

15. Malinovsky FG, Batoux M, Schwessinger B, Youn JH, Stransfeld L, Win J, et al. Antagonistic Regulation of Growth and Immunity by the Arabidopsis Basic Helix-Loop-Helix Transcription Factor HOMOLOG OF BRASSINOSTEROID ENHANCED EXPRESSION2 INTERACTING WITH INCREASED LEAF INCLINATION1 BINDING bHLH1. Plant Physiol. 2014 Mar 1;164(3):1443–55.

14. Bahar O, Pruitt R, Luu DD, Schwessinger B, Daudi A, Liu F, et al. The Xanthomonas Ax21 protein is processed by the general secretory system and is secreted in association with outer membrane vesicles. PeerJ. 2014 Jan 7;2:e242.

13. Wang E, Schornack S, Marsh JF, Gobbato E, Schwessinger B, Eastmond P, et al. A Common Signaling Process that Promotes Mycorrhizal and Oomycete Colonization of Plants. Current Biology. 2012 Dec 4;22(23):2242–6.
12. Han SW, Lee SW, Bahar O, Schwessinger B, Robinson MR, Shaw JB, et al. Tyrosine sulfation in a Gram-negative bacterium. Nature Communications. 2012 Oct 23;3:1153.

11. Dardick C, Schwessinger B, Ronald P. Non-arginine-aspartate (non-RD) kinases are associated with innate immune receptors that recognize conserved microbial signatures. Curr Opin Plant Biol. 2012 Aug;15:358–66.
10. Schwessinger B, Ronald PC. Plant innate immunity: perception of conserved microbial signatures. Annual Review of Plant Biology. 2012 Jun 2;63:451–82.

9. Albrecht C, Boutrot F, Segonzac C, Schwessinger B, Gimenez-Ibanez S, Chinchilla D, et al. Brassinosteroids inhibit pathogen-associated molecular pattern–triggered immune signaling independent of the receptor kinase BAK1. PNAS. 2012 Jan 3;109(1):303–8.

8. Ntoukakis V*, Schwessinger B*, Segonzac C, Zipfel C. Cautionary notes on the use of C-terminal BAK1 fusion proteins for functional studies. Plant Cell. 2011 Nov;23:3871–8.
* These authors contributed equally to the work

7. Roux M*, Schwessinger B*, Albrecht C, Chinchilla D, Jones A, Holton N, et al. The Arabidopsis Leucine-Rich Repeat Receptor-Like Kinases BAK1/SERK3 and BKK1/SERK4 Are Required for Innate Immunity to Hemibiotrophic and Biotrophic Pathogens. Plant Cell. 2011 Jun 21;23:2440–55.
* These authors contributed equally to the work

6. Schwessinger B, Roux M, Kadota Y, Ntoukakis V, Sklenar J, Jones A, et al. Phosphorylation-Dependent Differential Regulation of Plant Growth, Cell Death, and Innate Immunity by the Regulatory Receptor-Like Kinase BAK1. PLoS Genet. 2011 Apr;7:e1002046.

5. Nekrasov V, Li J, Batoux M, Roux M, Chu ZH, Lacombe S, et al. Control of the pattern-recognition receptor EFR by an ER protein complex in plant immunity. Embo J. 2009 Nov 4;28:3428–38.

4. Haas BJ, Kamoun S, Zody MC, Jiang RH, Handsaker RE, Cano LM, et al. Genome sequence and analysis of the Irish potato famine pathogen Phytophthora infestans. Nature. 2009 Sep 17;461:393–8.

3. Conti L, Price G, O’Donnell E, Schwessinger B, Dominy P, Sadanandom A. Small ubiquitin-like modifier proteases OVERLY TOLERANT TO SALT1 and -2 regulate salt stress responses in Arabidopsis. Plant Cell. 2008 Oct;20:2894–908.

2. Schwessinger B, Zipfel C. News from the frontline: recent insights into PAMP-triggered immunity in plants. Curr Opin Plant Biol. 2008 Aug;11:389–95.

1. Zipfel, C., Schwessinger, B, Roux, M., and Jones, J.D.G. Genetic analysis of PAMP‐triggered immunity in Arabidopsis. International Society for Molecular Plant‐Microbe Interactions, St. Paul, Minnesota. Biology of Plant-Microbe Interactions. 2008.
 

2 thoughts on “Bio 2

  1. Pingback: Don’t judge too fast! | lushgreengrassatafridayafternoon

  2. Pingback: Be positive! From witch hunts to the new reward culture | lushgreengrassatafridayafternoon

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