Current Research

2007-present: BBSRC Crop Science Initiative: Exploiting the Phytophthora infestans genome to determine targets for sustainable potato protection.

An important research goal in the fight against potato late blight, caused by the Oomycete Phytophthora infestans, is to identify pathogen effector proteins likely to be secreted during infection and translocated into host cells to manipulate host metabolism and defence responses. Many of these effectors are targeted by host surveillance systems to trigger resistance that is effective and potentially durable. AVR3a, the first effector characterized from P. infestans, was found to contain N-terminal RxLR and dEER motifs required for transport across the host plasma membrane. Developing genomic resources have allowed large-scale computational screening for this conserved motif to reveal approximately 500 rapidly diverging P. infestans effectors.

We are cloning candidate P. infestans RxLR-EER effectors that are induced during plant infection, some containing predicted PFAM domains. These effectors are being expressed transiently in collections of cultivated and wild Solanum species to identify sources of resistance (R) genes that recognise specific effectors. In this way, we have identified Avr2, recognised by the R2 resistance gene which maps to the durable resistance locus present in cv. Stirling. By silencing effectors in P. infestans we have identified effectors that are functionally essential and effectors that are redundant for virulence. Furthermore, studying allelic variation of avirulent effectors in isolates from around the world reveals the selection pressures imposed on these genes in pathogen populations.

I am also silencing host targets of P. infestans effectors that interact in Yeast-2-hybrid experiments using Tobacco Rattle Virus in N. benthamiana. Functional analyses of both the P. infestans effector and its virulence target will aid dissection of the key regulatory pathways of potato targeted by P. infestans during infection in order to distinguish those that could be targeted to control disease development.

Research History

2004-2007: Systems Biology, Dr Paul Birch and Ian Toth, Plant Pathogology, SCRI, Invergowrie, Great Britain

• The systems biology project was focused on the soft-rot pathogen, Pectobacterium. atrosepticum (Pba) and its interaction with potato.
• I was involved in plant gene selection for the design of a potato microarray (Agilent).
• Investigating the role of Pba effectors in the suppression of plant basal resistance responses.
• Exploring the role of a WRKY transcription factor in potato that conveys resistance against Pba.

October 2001-March 2005, BBRSC case PhD studentship: Utilising model systems and crop species to discover and characterise novel genes in plant disease resistance.

• Work in Gary Loake’s group at Edinburgh University employed knock-out, over-expression and activation-tagged Arabidopsis mutants to investigate defence responses induced by biotrophic, necrotrophic and non-host pathogens.
• My aim in Paul Birch’s group at SCRI was to functionally analyse genes involved in the resistance responses of particular potato cultivars induced by interactions with Phytophthora infestans.
• Under the guidance of Christophe Lacomme, A potato virus X (PVX)-based Virus Induced Gene Silencing (VIGS) system was developed for tetraploid and wild diploid potato cultivars.
• In addition, a VIGS functional screen in the model Solanaceae, Nicotiana benthamiana was established to investigate the role of plant defence genes further using Tobacco Rattle Virus (TRV).
• The 2nd major finding of the PhD was the role of one defense gene, the protease cathepsin B during the hypersensitive response (HR).

I gained field pathology experience as a Temporary Growing Potato Seed Crop Inspector with the Scottish Executive Environment and Rural Affairs Department during July 1999, 2000 and 2001.

Bachelor of Science with Honours Genetics - 1997 - 2001: Institute of Cell and Molecular Biology, the University of Edinburgh, UK.

Education

I was involved in designing, writing and teaching a Virus-Induced Gene Silencing Workshop with Ingo Hein, Leighton Pritchard, Paul Birch from SCRI with Dave Berger, Eddie Ventre and Irene van Nugteren held at the Forestry and Agricultural Biotechnology Institute (FABI), Pretoria, South Africa on the 11-16 February 2008 funded by the Royal Society.

External Examiner for a University of Edinburgh Masters thesis.

Outreach

I recently made a science exhibit for a Women in STEM (science, technology, engineering and maths) event at Dundee Sensation science centre. After visiting my good friend Lindsay Hogg who works at Glasgow Science Centre where I saw the “You choose the news” game on stem cells and decided to adapt this to focus on GM technology.

The game involves a mixture of personal interviews, a newsreader, a roving reporter and media clips reflecting positive, negative and neutral attitudes towards GM technology. The purpose of the game is to let children choose which clips to combine to achieve a balanced news report.

After securing funding from the British Society of Plant Pathology I recreated the game focusing on the forthcoming EU pesticide ban and the potential of using GM technology as a result. The project was possible thanks to my friend Jenny Ross, a TV camera operator for STV North, filming the project for her own personal development and all volunteers who acted in the game or helped behind the scenes (Miles Armstrong, Paul Birch, Vivian Blok, Susan Breen, Emma Douglas, Andy Flavell, Alastair Gilroy, Ingo Hein, Hazel McLellan, Amarnath Thirugnana Sambandam).

“You choose the news” can be played on the SCRI website.

Recent Publications

• Birch, P.R.J., Armstrong, M., Bos, J., Boevink, P., Gilroy, E.M., Taylor, R.M., Wawra, S., Pritchard, L., Conti, L., Ewan, R., Whisson, S.C., van West, P., Sadanandom, A. and Kamoun S. Towards understanding the virulence functions of RXLR effectors of the oomycete plant pathogen Phytophthora infestans. Journal of Experimental Botany. 2009 Feb 9. [Epub ahead of print]
• Birch, P.R.J, Boevink, P.C., Gilroy, E.M., Hein, I., Pritchard, L. and Whisson S.C. 2008. Oomycete RXLR effectors: delivery, functional redundancy and durable disease resistance. Current Opinion in Plant Biology 11, 373-9.
• Gilroy, E.M., Hein, I., van der Hoorn, R., Boevink, P.C., Venter, E., McLellan, H., Canalez, E., Kaffarnik, F., Hrubikova, K., Shaw, J., Holeva, M., Borras-Hidalgo, O., Pritchard, L., Loake, G.J., Lacomme, C., Birch, P.R.J. 2007. Involvement of Cathepsin B in the Plant Disease Resistance Hypersensitive Response. Plant Journal 52, 1-13.
• Whisson, S.C., Boevink, P.C., Moleleki, L. , Avrova,  A.O., Morales, J.G., Gilroy, E.M., Armstrong,  M.R.,  Grouffaud, S., van West, P., Chapman, S., Hein, I., Toth, I.K., Pritchard, L. and Birch, P.R.J. 2007. A translocation signal for delivery of oomycete effector proteins into host plant cells. Nature 450, 115-118. (doi:10.1038/nature06203)
• Faivre-Rampant., O., Gilroy, E.M.,  Hrubikova, K., Hein, I., Millam, S., Loake, G.J., Birch, P., Taylor, M. and  Lacomme, C. 2004. Potato Virus X-Induced Gene Silencing in Leaves and Tubers of Potato. Plant Physiology 134, 1308-1316.
• Tani, H., Chen, X., Nurmberg, P., Grant., J.J., SantaMaria, M., Chini, A., Gilroy, E.M., Birch, P.R.J. and Loake, G.J. 2004. Activation Tagging in Plants: A Tool for Gene Discovery. Integrative and Functional Genomics 4, 258-266.
• Avrova, A.O., Taleb, N., Rokka, V.M., Heilbronn, J., Campbell, E., Hein, I., Gilroy, E.M., Cardle, L., Bradshaw, J.E., Stewart, H.E., Fakim, Y.J., Loake, G. and Birch, P.R.J. 2004. Potato oxysterol binding protein and cathepsin B are rapidly up-regulated in independent defence pathways that distinguish R gene-mediated and field resistance to Phytophthora infestans. Molecular Plant Pathology 5,  45-56.
• Birch, P.R.J., Avrova, A.O., Armstrong, M., Venter, E., Taleb, N., Gilroy, E.M., Phillips, M.S. and Whisson, S.C. 2003. The potato-Phytophthora infestans interaction transcriptome. Canadian Journal of Plant Pathology 25, 226-231.

Posters

(View all posters)

Attachment	Size
A step closer to blackleg control: Genomics opens our eyes to the true nature of Erwinia and its interaction with plants	212.62 KB
The Role of Protease Cathepsin B during non-host HR	203.17 KB
The Role of Protease Cathepsin B during non-host HR	147.75 KB
VIGS for functionally analysing novel defence genes in potato	170.77 KB
Viral-induced gene silencing (VIGS) vector development for functional studies in crop plants	154.46 KB
Viral-induced gene silencing (VIGS) vector development for functional studies in Solanaceae	192.55 KB
Role of Erwinia carotovora subsp. atroseptica harpins in the manipulation of host defences	115.22 KB
Role of Pectobacterium atrosepticum (Pba) effectors in the manipulation of host defences	414.71 KB
Evolutionarily distinct RXLR effectors from distantly related oomycetes target the plant exocyst	1000.56 KB
Is KIPI30 the main virulence target of the Phytophthora infestans effector protein Avr3a?	175.3 KB
You choose the news	1.13 MB
Exploiting the Phytophthora infestans genome to determine targets for sustainable potato protection	597.58 KB