Research in the Haber Lab

We are engaged in studying how breaks in the DNA double helix are repaired and in certain cellular processes that they initiate. Such DNA double strand breaks, or DSBs, can lead to chromosome instability and can be lethal if not repaired. DSBs may result from irradiation or mutagenic chemicals. They may also arise during DNA replication as a product of stalled replication forks and they can also arise in specialized processes such as mating type switching in yeast or during the process of creating immunoglobulins. Interest in DSBs also stems from the fact that DSBs sometimes result in aberrations such as chromosomal rearrangements which in some organisms can lead to the formation of cancers.

Our lab uses the budding yeast, S. cerevisiae, as an experimental organism to study DSBs, because it possesses many characteristics of more complex organisms, yet offers many advantages of studying a simpler, unicellular organism. These include its small genome size and its utility in laboratory and genetic procedures. Interest in yeast as a laboratory organism grew in the 1980's due to the ability to introduce DNA into yeast cells by transformation and thereby alter its genetic content. Prior to this, though, there was a substantial interest in yeast from both the genetic and biochemical viewpoints, which provided a large body of information about yeast.

To study DSBs, we induce expression of an endonuclease within the yeast cell that creates a single DSB within the entire genome and then we employ a variety of techniques to follow what happens. We are interested in the mechanisms of DNA repair, either by homologous DNA recombination or by DNA end-joining. We are also interested in processes that DSBs initiate, such as cell cycle arrest and the process of mating type switching. At this website we have provided a brief introduction to the study of break-induced DNA recombination as well as more detailed descriptions of our research interests. For scientists, we have also included a selection of detailed lab protocols and a list of some of our recent publications.