Fungal plant pathogens require tight control over the expression of their effector genes which encode secreted proteins that facilitate host invasion. Failure to express such genes at the appropriate time or location during host invasion may lead to interception by the plant host, and thus failure of the infection. In many fungal plant pathogens, effector genes are not randomly distributed over the genome, but localized in distinct genomic regions that are enriched in transposable elements (TEs). TEs can transpose over the genome and thereby affect gene expression or functionality, which may negatively affect the organism. To control TE activity, TE-containing genomic regions are usually structured as heterochromatin, a highly condensed genomic structure that is not accessible to the transcription machinery. Consequently, TEs are generally silenced. Due to the close proximity of many effectors to TEs, they may be held in a co-silenced state. Consequently, upon encountering a host-plant, pathogens will require de-condensation of heterochromatin to appropriately express effector genes. To investigate whether the genomic regions containing effector genes are actively de-condensed during host colonization, we are using chromatin immunoprecipitation (ChIP) to selectively isolate heterochromatic DNA of the broad host-range fungus Verticillium dahliae grown in vitro and in planta. Additionally, we map the genome-wide positioning of nucleosomes to investigate differences between effector genes in TE-rich regions and genes that reside within core regions of the genome. This research will lead to a better understanding of the regulation of effector genes and reveal the importance of chromatin dynamics in this process.
|Title of host publication||Abstract Book 29th Fungal Genetics Conference Asilomar 17, Pacific Grove, CA, USA 14-19 March 2017|
|Publisher||Genetics Society of America|
|Publication status||Published - 2017|
|Event||29th Fungal Genetics Conference - Asilomar Conference Center, Pacific Grove, CA, United States|
Duration: 14 Mar 2017 → 19 Mar 2017
|Conference||29th Fungal Genetics Conference|
|City||Pacific Grove, CA|
|Period||14/03/17 → 19/03/17|
Kramer, H. M., Cook III, D. E., Seidl, M. F., & Thomma, B. P. H. J. (2017). Regulation of fungal effector gene expression through chromatin de-condensation. In Abstract Book 29th Fungal Genetics Conference Asilomar 17, Pacific Grove, CA, USA 14-19 March 2017 (pp. 56-56). Genetics Society of America.