Eisen Lab
Phylogenomics and the Origin of Novelty (Eisen Lab at U. C. Davis)
The Eisen lab focuses on the issues relating to the origin of novelty in biological systems. In particular, we use a phylogenomic approach in which we combine evolutionary reconstructions with genome analyses to try and understand the genomic basis for the origin of novelty.
Currently, the lab focuses on how novelty can be generated from symbioses and communities of organisms, especially microbes. Some of our current research topics in this area are:
Phylogenomics and the bacterial tree of life
In order to gain a full appreciation of microbial diversity and genomics, we need to understand more about poorly studied branches in the tree of life. To help with this, we have been funded by the NSF Tree of Life program to sequence and characterize genomes from phyla of bacteria for which there are no complete genomes available. For more information see http://www.tigr.org/tol
The evolution of intracellular symbioses
One of the simplest ways for organisms to acquire new functions is to engage in symbioses with other species. Perhaps the most pervasive symbioses leading to new functions are those involving the plastid and mitochondria organelles of eukaryotes. In addition, there are 1000s of other symbioses between eukaryotes and intracellular bacteria at various stages of evolution. We are interested in characterizing a diversity of such symbioses to better understand what the rules are for these symbioses to evolve.
The functioning of communities of microbes in nature
Intracellular symboises are pervasive and important but it is becoming clear that communities of microorganisms can also allow new functions to evolve or be acquired by various species. Examples include the gut microbes of cellulolytic organisms, the mats found in hotsprings, and the planktonic microbes found in the open ocean. We are working on methods to characterize such microbial communities and are applying these methods to characterize some model microbial communities.
