Professor Peter Langridge
Australian Centre for Plant Functional Genomics:
The University of Adelaide, Waite Campus, Adelaide
SA 5005
Click here for an information sheet:
Email: peter.langridge@acpfg.com.au
The Big Picture
Cereal Biotechnology
The Cereal Biotechnology research group is lead by Professor Peter Langridge with most of the research now being conducted for the Australian Centre for Plant Functional Genomics. The laboratory still has strong ties with the University of Adelaide through postgraduate teaching.
The research group also contributes to the following research organisations:
- MPB CRC
- GRDC National Wheat and Barley Molecular Marker
- Programs
The Short-Term Goals
- Molecular markers for the barley and wheat genomes.
- Transition of marker development to implementation into cereal breeding programs.
- Examining meiosis and the genes that control chromosome pairing in wheat.
- Genome structure manipulation, fungal disease resistance in cereals,
- Plant thioredoxins.
- Identification of genes that have a major role in wheat and barley grain development
Cereal Disease Resistance
Identify genes that are involved in and responsible for the resistance of barley to the pathogenic fungus R. secalis. Initially eliminating the vast number of genes
that are not specifically expressed in the barley/scald interaction, two interactions, which result in either a resistant or a susceptible phenotype, were subtracted to remove the non-specific background expression.
Differentially expressed genes between both types of interactions are enriched and investigated further.
These genes represent candidates for encoding proteins specifically involved in disease resistance.
Besides an understanding of the basic mechanisms involved in resistance to pathogens, this approach can provide tools for genetically engineering improved resistance in barley cultivars.
Matrix Attachment Regions (MARs)
Transformation / Genome Structure
Aims to improve the efficiency and stability of transgenesis in wheat and canola.
Outcomes will include improved transformation frequencies and enhancement and/or
stability of integrated transgenes. This project addresses a key area of community concern related to genetically modified (GM) crops, that is, the stability of transgenes and the prediction of transgene behaviour and whether or not MAR elements have a functional role in plant genome organisation.
Meiosis Studies
The ability of allohexaploid bread wheat (Triticum aestivum L.) to act as a diploid, given that it contains three closely related genomes - A, B and D, makes it a perfect model to investigate genetic control, chromosome pairing and recombination during meiosis.
In order to understand the molecular basis of chromosome pairing and recombination, a number of candidate genes have been isolated from the wheat genome that may be
involved in early meiosis as well as several key developmental processes. Characterisation and efficacy (through construct development) is currently being conducted on selected candidate genes.
Molecular Marker Studies
Research in this laboratory is divided into three main areas:
- Marker Implementation/Validation
- Provides molecular marker screening services for the wheat and barley breeding programs and further develops markers from their initial discovery in the mapping programs to robust markers suitable for routine screening. Currently, emphasis is given to developing PCR-based assays such as microsatellites and high throughput
- DNA extraction techniques.
Conventional Mapping
Utilizes segregating populations, usually Doubled haploids of wheat or barley, to identify marker trait associations. These populations are selected to segregate for a large range of disease, abiotic and quality traits. A large number of marker/trait associations for both single genes and Quantitative Trait Loci have now been identified and are in routine use in the implementation program.
Association Mapping
Examine the potential of directly exploiting the trait data from breeders' populations over successive generations while using selective genotyping to identify marker/trait associations in contemporary germplasm derived from current breeding programs. Though the general principles of marker/trait association analysis in this type of population are reasonably well established, additional simulation and analytical studies are required to establish the optimal designs in terms of both the number of lines and the complexity of the pedigrees. This project represents a major departure from the conventional approach of map-based analysis of traditional marker trait associations.
Thioredoxin Studies
The h class of thioredoxins represent the largest number and most widely distributed group of thioredoxins. h-type thioredoxins are expressed in a range of tissues and at differentdevelopmental stages. Plant thioredoxin h mRNAs have the highest expression levels in rapidly growing cells and from EST data appear to be present in all plant tissues. Different members of the thioredoxin h-class have been purified from the endoplasmic reticulum and plasma membrane, and located in the nucleus by in situ hybridisation. In addition, thioredoxin h proteins have been located in the sieve tubes of several plants despite nothaving a signal peptide.
As the quantity of data regarding thioredoxin number, expression pattern and intracellular distribution has increased, it has become apparent that the existing thioredoxin classification system, particularly with regard to h-type thioredoxins, is oversimplified. The current project being investigated has identified a new subclass of plant thioredoxin h.
Further characterization of this new subgroup is to be conducted, with the expectation thatinformation obtained will be useful for the phylogenetic relationships of all plant thioredoxins.
| Laboratory Members and Areas of Research
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The Langridge lab is composed of an interdisciplinary team that conducts world-class research in the broad field of cereal genomics.
Cereal Disease Resistance
Dr Amanda Able, Professor Peter Langridge, Dr Klaus Oldach
Funding: ARC Discovery Project and ACPFG.
Matrix Attachment Regions (MARs)
Transformation / Genome Structure
Dr Jason A Able.
Funding: GRDC, MPB CRC.
Meiosis Studies
Project aims:
- Identify genes that are differentially expressed between wild type and meiotic mutants of wheat
- Identify genes with interesting temporal expression during meiotic development in the wheat anther
Dr Jason A Able
Funding: MPB CRC, Adelaide University .
Molecular Marker Studies
Dr Ken Chalmers
Current
Applications Submitted or Planned
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A statement on most significant contributions to this research field |
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| Other evidence of impact and contributions to the field
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Member, Genetic Manipulation Advisory Committee (GMAC) since 1994,
Member, Gene Technology Technical Advisory Committee (GTTAC).
Involved in the international coordination of public research programs in wheat and barley genetics aimed at enhancing access of gene technologies to breeding programs in the developed and developing worlds.
| Publications - Last 5 Years
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Dong C, Whitford R, Langridge P (2002) A mismatch repair gene liked to the Ph2 locus of wheat. Genome 45: 116-124.
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Chalmers K, Campbell AW, Kretschmer J, Karakousis A, Henschke PH, Pierens S, Harker N, Pallotta M, Cornish GB, Shriflou M, Rampling L, McLauchlan A, Daggard G, Sharp P, HoltonT, Sutherland M, Appels R, Langridge P (2001) Construction of three linkage maps in bread wheat (Triticum aestivum). Australian Journal of Agricultural Research 52: 1089-1119.
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Baumann U, Juttner J, Bian XY, Langridge P (2000) Self-incompatibility in the grasses. Annals of Botany 85 (Supplement A): 203-209.
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Huang C, Barker SJ, Langridge P , Smith FW, Graham RG (2000) Zinc deficiency up-regulates expression of high-affinity phosphate transporter genes in both phosphate-sufficient and -deficient barley roots. Plant Physiology 124: 415-422.
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Jefferies SP, Pallotta MA, Paull JG, Karakousis A, Kretschmer JM, Manning S, Islam AKMR, Langridge P , Chalmers KJ (2000) Mapping and validation of chromosome regions conferring boron toxicity tolerance in wheat (Triticum aestivum). Theoretical and Applied Genetics 101: 767-777.
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Jefferies SP, Barr AR, Islam AKMR, Karakousis A, Kretschmer JM, Manning S, Chalmers KJ, Langridge P (1999) Mapping genes conferring boron tolerance in barley. Theoretical and Applied Genetics 98: 1293-1303.
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Jefferies SP, Barr AR, Karakousis A, Kretschmer JM, Manning S, Chalmers KJ, Nelson JC, Islam AKMR, Langridge P (1999) Mapping of chromosome regions conferring boron toxicity tolerance in barley (Hordeum vulgare L.) Theoretical and Applied Genetics 98: 1293-1303.
| Ten Career-Best Publications
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