Search bioRxiv⌕ Search

Biology subjects

Buccitelli, C.

Publications and source records attributed to Buccitelli, C..

3 recordsLinked to original sources

Systems approaches identify the consequences ofmonosomy in somatic human cells

Chromosome loss that results in monosomy is detrimental to viability, yet, it is frequently observed in cancers. How cancers survive with monosomy is unknown. Using p53 deficient monosomic cell lines, we found that chromosome loss impairs proliferation and genomic stability. Transcriptome and proteome analysis revealed a partial compensation of the gene dosage changes that mitigates the effects of chromosome loss. Monosomy triggers global gene expression changes that differ from the effects of trisomy. We show that ribosome biogenesis and translation were commonly downregulated in monosomic cells, likely due to haploinsufficiency of ribosomal genes. The ensuing ribosome biogenesis stress triggers the p53 pathway and G1 arrest when TP53 is reintroduced into monosomic cells. Accordingly, impaired ribosome biogenesis and p53 inactivation are associated with monosomy in cancer. Our first systematic study of monosomy in human cells explains why monosomy is so detrimental and how loss of p53 enables its incidence in cancer.

systems biology↗

Bulk and single-cell gene expression profiling of SARS-CoV-2 infected human cell lines identifies molecular targets for therapeutic intervention

The coronavirus disease 2019 (COVID-19) pandemic, caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an ongoing global health threat with more than two million infected people since its emergence in late 2019. Detailed knowledge of the molecular biology of the infection is indispensable for understanding of the viral replication, host responses, and disease progression. We provide gene expression profiles of SARS-CoV and SARS-CoV-2 infections in three human cell lines (H1299, Caco-2 and Calu-3 cells), using bulk and single-cell transcriptomics. Small RNA profiling showed strong expression of the immunity and inflammation-associated microRNA miRNA-155 upon infection with both viruses. SARS-CoV-2 elicited approximately two-fold higher stimulation of the interferon response compared to SARS-CoV in the permissive human epithelial cell line Calu-3, and induction of cytokines such as CXCL10 or IL6. Single cell RNA sequencing data showed that canonical interferon stimulated genes such as IFIT2 or OAS2 were broadly induced, whereas interferon beta (IFNB1) and lambda (IFNL1-4) were expressed only in a subset of infected cells. In addition, temporal resolution of transcriptional responses suggested interferon regulatory factors (IRFs) activities precede that of nuclear factor-{kappa}B (NF-{kappa}B). Lastly, we identified heat shock protein 90 (HSP90) as a protein relevant for the infection. Inhibition of the HSP90 charperone activity by Tanespimycin/17-N-allylamino-17-demethoxygeldanamycin (17-AAG) resulted in a reduction of viral replication, and of TNF and IL1B mRNA levels. In summary, our study established in vitro cell culture models to study SARS-CoV-2 infection and identified HSP90 protein as potential drug target for therapeutic intervention of SARS-CoV-2 infection.

systems biology↗

Efficient strategies to detect genome editing and integrity in CRISPR-Cas9 engineered ESCs

CRISPR-mediated genome engineering provides a powerful tool to study the function of genes and proteins. In the past decades, the advances in genome and transcriptome sequencing techniques have shed light on the genetic causes underlying many human diseases, such as neurodevelopmental disabilities or cancer. Sometimes, a single point-mutation in a protein coding gene has been identified as the primary cause of the disease. CRISPR-Cas offers the possibility to introduce or remove such a mutation of interest to understand disease mechanisms and even bears therapeutic potential. We describe the adaptation of an experimental strategy that allows the mutation of protein residues in mouse embryonic stem cells (ESCs) and propose a new screening method, Mismatch-qPCR, to reliably detect editing events in clonal cell lines as an alternative to restriction digest or Sanger sequencing. Finally, we show that RNA-Sequencing (RNA-Seq) data or low-coverage genomic sequencing data can be used to detect large chromosomal deletions and rearrangements that frequently occur at the CRISPR-targeting site.

genetics↗