Human adenoviruses are a useful tool to understand basic cellular biology in addition to viral infections. Historically, cellular splicing was first discovered in adenovirus, but other cellular processes, such as double-strand break repair and aggresome formation, have been further elucidated through adenoviral infection. The adenovirus protein E4 11k has been shown to disrupt cytoplasmic processing bodies (p bodies), which are not well-understood but are involved in mRNA metabolism. Several p body proteins were found to be reorganized in the cytoplasm with adenovirus serotype 5 (Ad5) able to cause the colocalization of these p body proteins with aggresomes. The p body protein Lsm1 has been found to colocalize with E4 11k in aggresomes, but Edc3 and Pat1b are two p body proteins that have not been as well-studied in adenovirus-infected cells. Cells were treated with cadmium chloride or infected with wild-type and mutant viruses before staining them to visualize the p body proteins and a marker for viral infection by confocal microscopy. We were able to determine that the presence of E4 11k was not necessary for relocalization of either Lsm1 or Edc3 to aggresomes, while Pat1b did not localize to aggresomes under any conditions tested. We wanted to characterize Pat1b relocalization further so we counted the number of Pat1b foci in mock-infected cells and then the virally-infected cells, and were able to determine that Ad5 E4 11k is necessary and sufficient to induce an increase in cytoplasmic Pat1b foci. We also determined that this increase in Pat1b foci appears to be serotype-specific when compared to Ad9 and Ad12 E4 11k protein. The lack of apparent change with Pat1b localization with Ad9 E4 11k expression was a novel finding that suggests there may be something unique about Pat1b and p body localization.
We would like to thank Dr. Gary Ketner at Johns Hopkins University for viruses and cell lines, Dr. Patrick Hearing at Stony Brook University for cell lines, the Georgia College Center for Teaching and Learning for the Faculty Research Grant and GC Journeys mini-grant that funded much of this work, and the Georgia College Department of Biological and Environmental Sciences for their continued support of our research.
Karen, Kasey A.; Randolph, La`Quita; Neubrecht, Kevin; and Vincent, Heather
"The Role of Adenovirus Serotype 5 E4 11k in the Relocalization of the Cellular P Body Proteins,"
Georgia Journal of Science, Vol. 81, No. 2, Article 9.
Available at: https://digitalcommons.gaacademy.org/gjs/vol81/iss2/9