5 September 2022

This project fits within Pou 2: Poutokomanawa, exploring the molecular basis of effector localization within the host cell and if they are recognized by the host plant. The projects subject is strongly linked to the aim to determine the basis of Phytophthora specificity, comparing infection of narrow- and broad-host range pathogenic Phytophthora.

This project is the second step to gain new insight into conserved effectors within Phytophthora species based on our novel genomics data.

Project Summary 

The oomycete class of Phytophthora species is responsible for some of the most devastating plant diseases, which cause significant economic losses worldwide every year. Many Phytophthora species are extremely invasive pathogens found in forestry, horticulture and native plants on every continent. This project aims to help protect hosts species of Phytophthora pathogens by identifying conserved gene products responsible for pathogenicity that contribute to the resulting plant disease. We have recently identified conserved genes of interest from a variety of Phytophthora species by sequencing and genomic analysis that are potentially translocated into the host cell. This project aims to gain first insight into protein localization within the host and study protein characteristics.

This project integrates into the bigger framework of plant pathology within Bioprotection Aotearoa, which aims to understand Phytophthora pathogens. The student will have the opportunity to work within an active national and international research network. Findings of this project are expected to be useful in the prevention of wider damage caused by Phytophthora species and the wider range of oomycota.

Objective

Ecological and economic damage caused by the extremely invasive Phytophthora species has been increasing over a wide range of host plants in recent years. As such, there is currently an urgent need to understand how these microbes invade their hosts. This project aims to study previously identified conserved effector proteins to understand their contribution to pathogenicity. The objective of this project is to combine computer based protein modelling, sequence and network analysis with wet lab experiments to understand the effectors characteristics, cellular localization in plants and potential recognition, inducing hypersensitive response. The results of this project will be pertinent to the identification of new susceptibility and resistance genes, which are key to novel development of countermeasures against these harmful pathogens.

Background

Phytophthora species are the causal agent of many root rots, diebacks and needle cast diseases in a multitude of hosts. Their irremediable destructive effects and often resistance to treatment makes them a large threat to ecosystems, horticulture and forestry. The hidden infection of the roots by soil born Phytophthoras is often discovered at a late stage of infection, resulting in irreparable damage or death of the host. In Aotearoa, Kauri dieback induced by P. agathidicida is a clear danger to this native tree and the associated ecosystem. Furthermore, yields of woody crops like Radiata pine and Douglas fir have been reduced by Phytophthora species like P. pluvialis and P. cinnamomi in recent outbreaks.

Though awareness of significant impact by Phytophthora has resulted in the generation of sequence data and effector studies, existing knowledge on Phytophthora conserved effectors remains insufficient for the development of countermeasures.

Proposed methodology

We propose to use computational protein modelling (AlphaFold2) to study the 3D structure of conserved but unknown effector proteins originally identified from P. pluvialis and conserved in a broad variety of other Phytophthora species. In addition, a detailed sequence analysis will be performed and used to prepare a sequence similarity network, combining the EFI – Enzyme Similarity Tool and Cytoscape. To complement the computer–based approach the student will transiently express effectors (tagged with an N-terminal fluorescent protein) by Agrobacterium infiltration in Nicotiana benthamiana for 48 h. This will be followed by documentation of tissue health (or cell death) within the infiltration sites and protein localization by confocal microscopy.

These experiments will allow the student to gain significant experiences in sample preparation and computer-based protein analysis often used in modern phytopathology.

Scholarship Amount

A total of $6000 tax free is available for each scholarship. Fortnightly payments will be made for the duration of the scholarship, with the final payment of $1000 on receipt of the approved student project report.

Application Process

Please download and complete the BA Summer scholar student application form 2022 (Word doc).  Send your completed application form, along with a CV and a Cover Letter detailing why you feel you wouldbe suitable for this position.

Email applications to Elena Johnson [email protected] before the closing date 23 September, 2022. 

 


Location:  Christchurch
Institution: University of Canterbury
Supervisor(s): Dr. Claudia Meisrimler
Other staff Sophie Eccersall, Renwick Dobson
Pou:  Pou 2: Poutokomanawa
Project: Project 2.4: Exploring the molecular basis of host specificity
Application Form:  Download and complete the BA Summer scholar student application form 2022 (Word doc)
Apply to:  Email applications including a CV and Cover Letter to Elena Johnson [email protected]
Applications close:  Friday 23rd September 2022