About the Project
Despite the vital role of gametes in plant fertility, seed production and food security, we have limited knowledge of the mechanisms involved in their development. This research aims to uncover the mechanisms that underlie key decisions in plant gamete development and the important role of germline gene networks in plant and crop fertility.
Through screens in the genetic model Arabidopsis thaliana, we have identified several key regulators of male gamete development including the transcription factor DUO1, which is widely conserved and present in important food crop plants such as tomato and rice (Kim et al. 2008; Brownfield et al. 2009). Our work has established a new regulatory framework in plant germline development (Berger and Twell, 2011), and in recent BBSRC-funded work we have discovered a pair of novel zinc finger transcription factors (DAZ1 & DAZ2) that act downstream of DUO1. The DAZ1/DAZ2 proteins are predicted to act by repression of their targets by a mechanism involving the TOPLESS/TOPLESS-RELATED (TPL/TPR) family of co-repressors (Borg et al., 2014).
Project Aims & Description:
This project will explore the evolutionary conservation and mechanisms by which the DUO1-DAZ1/DAZ2 regulatory module coordinates male germ cell division and sperm differentiation in Arabidopsis and in the important crop species, tomato. Genetic and molecular analysis will be combined with comparative transcriptome analysis to uncover gene regulatory networks and their impact on sperm cell differentiation and plant fertility.The project seeks to establish the conservation of DAZ1/DAZ2 function in flowering plants, to identify DAZ1/DAZ2 target genes and to model how the DAZ1/DAZ2 regulon is integrated with the wider gene network under DUO1 control.
The research is expected to deliver novel information and tools of potential value in plant biotechnology and breeding applications such as hybrid seed production and the control of gene flow in transgenic crops.
The project presents an ideal opportunity for challenging research and novel discoveries in a well-supported environment. The successful candidate will receive an excellent grounding in plant molecular genetics, and cell biology techniques as well as in bioinformatics skills and the potential applications of fundamental research in plant biotechnology. Enthusiastic students with interests in plant & crop development and gene regulation and who work well in a team environment are encouraged to apply.
Techniques that will be undertaken during the project:
Comparative transcriptomics (microarray & RNA-seq data)
HMM-based protein and motif search bioinformatics
Integration of ‘omics’ data and network modelling
Fluorescence and confocal laser scanning microscopy
Protein-interaction (yeast 2-hybrid and bimolecular fluorescence complementation)
Plant transformation and transient gene expression assays
Gene expression manipulation by overexpression analysis, use of T-DNA and CRISPR/Cas9 knockouts.
We are an equal opportunities employer and particularly welcome applications for Ph.D. places from women, minority ethnic and other under-represented groups.
References
Borg, M., Brownfield, L., Khatab, H., Sidorova, A., Lingaya, M. and Twell, D. (2011) The R2R3 MYB transcription factor DUO1 activates a male germline-specific regulon essential for sperm cell differentiation in Arabidopsis. Plant Cell 23:1-16
Borg, M., Rutley, N., Kagale, S. Hamamura, Y., Gherghinoiu, M., Kumar, S., Sari, U., Esparza-Franco, MA., Sakamoto, W., Rozwadowski, K., Higashiyama, T. and Twell, D. (2014). An EAR-dependent regulatory module promotes male germ cell division and sperm fertility in Arabidopsis. Plant Cell 26:1-17
Brownfield, L., Hafidh, S., Borg, M., Sidorova, A., Mori, T. and Twell, D. (2009) A plant germ cell-specific integrator of cell cycle progression and sperm specification PLoS Genet. 5: e1000430
Kim, H.J., Oh, S-A., Brownfield, L., Ryu, H., Hwang, I., Twell, D*. and Nam, H-G*. (2008) Control of plant male germline proliferation by SCFFBL17 degradation of cell cycle inhibitors. Nature 455, 1134-1137
Berger, F. and Twell, D. (2011) Germline specification and function in plants. Annu Rev Plant Biol 62:461-484.