Project description:Paenibacillus polymyxa is an agriculturally important plant growth promoting rhizobacterium (PGPR). Many Paenibacillus species are known to be engaged in complex bacteria-bacteria and bacteria-host interactions, which in other bacteria were shown to necessitate quorum sensing communication, but to date no quorum sensing systems have been described in Paenibacillus. Here we show that the type strain P. polymyxa ATCC 842 encodes at least 16 peptide-based communication systems. Each of these systems comprises a pro-peptide that is secreted to the growth medium and further processed to generate a mature short peptide. Each peptide has a cognate intracellular receptor of the RRNPP family, and we show that external addition of P. polymyxa communication peptides to the medium leads to reprogramming of the transcriptional response. We found that these quorum sensing systems are conserved across hundreds of species belonging to the Paenibacillaceae family, with some species encoding more than 25 different peptide-receptor pairs, representing a record number of quorum sensing systems encoded in a single genome.
Project description:Severe congenital neutropenia (CN) is a pre-leukemia syndrome that, in the majority of patients, is caused by heterogeneous ELANE mutations encoding neutrophil elastase (NE). To study leukemogenesis associated with CN we generated CN and CN/AML patient-specific induced pluripotent stem cells (iPSCs). Additional mutations in leukemia-relevant genes, CSF3R and RUNX1, were introduced using CRISPR/Cas9 gene-editing. Consequently, we performed in vitro embryoid body (EB)-based hematopoietic and myeloid differentiation of generated iPSC lines. On day 14-17 of EB-based differentiation, iPSC-derived CD45+CD34+ cells were harvested and mRNA was isolated using RNeasy Mini- or Micro Kit (Qiagen). Sequencing libraries were prepared using the TruSeq RNA Sample Prep Kit (Illumina). Poly (A) selected single-read and pair-read sequencing libraries were sequenced on the Illumina platform in order to compare the transcriptomes of CN and CN/AML iPSCs-derived HSPCs from 2 CN/AML patients. Next, we identified that BAALC knockout resulted in a dramatic induction of granulocytic differentiation and a significant reduction in proliferation of CN/AML iPSC-derived HSPCs. To identify BAALC-dependent leukemia-associated gene expression, we compared the transcriptomes of CN/AML iPSCs before and after BAALC KO using a similar approach described above for CN and CN/AML iPSCs-derived HSPCs.
Project description:Transcriptional profiling of the bacteria Paenibacillus vortex comparing control untreated cells with kanamycin treated cells after 18 hours of exposure. Goal was to determine the effect of the antibiotic kanamycin in concentration which affect the colony morphology on global bacteria gene expression.
