Lead Chief Investigator: Barbara Holland, University of Tasmania

Collaborating Chief Investigator: Daniel Ortiz-Barrientos


Our aim is to discover the different mechanisms or core network features that associate with traits of interest. 

For example, what are the common features of photoperiod response networks across all legumes?  What are the features that only associate with short-day plants or long-day plants?

Our approach

Given a pair of DNA sequences, there are well established approaches for determining homology and constructing sequence alignments. However, given a pair of gene networks this may not be straightforward. For closely related pairs of species, we will construct maps from the vertex set of one gene network into the vertex set of another.  

Next, given a set of networks from different species and a known phylogenetic tree that links the species, we will construct homology maps between the networks (i.e., alignments).  

From here, we hope to assign particular events (duplication, loss of genes, loss/gain of regulatory relationships) to particular edges of the phylogenetic tree. In effect, this would allow us to reconstruct ancestral gene networks at the internal nodes of a phylogenetic tree. This may only be possible over relative short evolution timescales because, across deep evolutionary time, the gene networks that act to produce similar functions may have evolved independently, i.e., networks may do similar things but not be homologous.  

Now, given an alignment of gene networks on a phylogenetic tree (or a set of small phylogenetic trees), we can associate the evolution of network features with information about traits in the species of interest. 

We aim to model the evolutionary processes that act on gene networks, including duplication events, mutations in regulatory regions, and lost/deleted genes.