Project description:Origin Recognition Complex Associated (ORCA) associates with repressive chromatin environments. We carried out H3K9me3 ChIP-seq to determine the affect of ORCA's loss on this repressive mark. Towards this end, we cultured U2OS osteosarcoma cells, performed control and ORCA knockdowns using siRNAs and then carried out H3K9me3 ChIP-seq to determine the regions in the genome which get affected upon ORCA knockdown. Examination of the levels of H3K9me3 in control and ORCA knockdown cells
Project description:Twenty-four patients were randomized to receive Orca-T alone (n=12) or Orca-T plus single-agent GVHD prophylaxis (n=12) to determine if Orca-T alone was non-inferior in preventing acute GVHD.
Project description:Origin Recognition Complex Associated (ORCA) associates with repressive chromatin environments. We carried out H3K9me3 ChIP-seq to determine the affect of ORCA's loss on this repressive mark. Towards this end, we cultured U2OS osteosarcoma cells, performed control and ORCA knockdowns using siRNAs and then carried out H3K9me3 ChIP-seq to determine the regions in the genome which get affected upon ORCA knockdown.
Project description:ORCA is an ORC associated protein that plays important roles in replication initiation as well as heterochromatin organization. We carried out ORCA ChIP-seq in U2OS cells synchronized at different stage of G1 phase to determine its genome wide localization. To understand the genomic features of ORCA binding regions, we also carried out Methylated DNA IP (MeDIP) followed by deep sequencing in U2OS cells to determine the genome wide localizatoin of methyl-CpG sites in U2OS cells and how ORCA bidning regions co-localize with this important repressive mark.
Project description:Acoustic sequences have been described in a range of species and in varying complexity. Cetaceans are known to produce complex song displays but these are generally limited to mysticetes; little is known about call combinations in odontocetes. Here we investigate call combinations produced by killer whales (Orcinus orca), a highly social and vocal species. Using acoustic recordings from 22 multisensor tags, we use a first order Markov model to show that transitions between call types or subtypes were significantly different from random, with repetitions and specific call combinations occurring more often than expected by chance. The mixed call combinations were composed of two or three calls and were part of three call combination clusters. Call combinations were recorded over several years, from different individuals, and several social clusters. The most common call combination cluster consisted of six call (sub-)types. Although different combinations were generated, there were clear rules regarding which were the first and last call types produced, and combinations were highly stereotyped. Two of the three call combination clusters were produced outside of feeding contexts, but their function remains unclear and further research is required to determine possible functions and whether these combinations could be behaviour- or group-specific.
Project description:There are currently no published data documenting the presence of retroviruses in cetaceans, though the occurrences of cancers and immunodeficiency states suggest the potential. We examined tissues from adult killer whales and detected a novel gammaretrovirus by degenerate PCR. Reverse transcription-PCR also demonstrated tissue and serum expression of retroviral mRNA. The full-length sequence of the provirus was obtained by PCR, and a TaqMan-based copy number assay did not demonstrate evidence of productive infection. PCR on blood samples from 11 healthy captive killer whales and tissues from 3 free-ranging animals detected the proviral DNA in all tissues examined from all animals. A survey of multiple cetacean species by PCR for gag, pol, and env sequences showed homologs of this virus in the DNA of eight species of delphinids, pygmy and dwarf sperm whales, and harbor porpoises, but not in beluga or fin whales. Analysis of the bottlenose dolphin genome revealed two full-length proviral sequences with 97.4% and 96.9% nucleotide identity to the killer whale gammaretrovirus. The results of single-cell PCR on killer whale sperm and Southern blotting are also consistent with the conclusion that the provirus is endogenous. We suggest that this gammaretrovirus entered the delphinoid ancestor's genome before the divergence of modern dolphins or that an exogenous variant existed following divergence that was ultimately endogenized. However, the transcriptional activity demonstrated in tissues and the nearly intact viral genome suggest a more recent integration into the killer whale genome, favoring the latter hypothesis. The proposed name for this retrovirus is killer whale endogenous retrovirus.