Emily Lee | Search bioRxiv

bioRxiv2016

Molecular signatures associated with ZIKV exposure in human cortical neural progenitors

Zika virus (ZIKV) infection causes microcephaly and has been linked to other brain abnormalities. How ZIKV impairs brain development and function is unclear. Here we systematically profiled transcriptomes of human neural progenitor cells exposed to Asian ZIKVC, African ZIKVM, and dengue virus (DENV). In contrast to the robust global transcriptome changes induced by DENV, ZIKV has a more selective and larger impact on expression of genes involved in DNA replication and repair. While overall expression profiles are similar, ZIKVC, but not ZIKVM, induces upregulation of viral response genes and TP53. P53 inhibitors can block the apoptosis induced by both ZIKVC and ZIKVM in hNPCs, with higher potency against ZIKVC-induced apoptosis. Our analyses reveal virus- and strain-specific molecular signatures associated with ZIKV infection. These datasets will help to investigate ZIKV-host interactions and identify neurovirulence determinants of ZIKV.

Genomics↗

bioRxiv2016

The mutational landscape of EGFR-, MYC-, and Kras- driven genetically-engineered mouse models of lung adenocarcinoma

Genetically-engineered mouse models (GEMMs) of cancer are increasingly being utilized to assess putative driver mutations identified by large scale sequencing of human cancer genomes. In order to accurately interpret experiments that introduce additional mutations, an understanding of the somatic genetic profile and evolution of GEMM tumors is necessary. Here, we performed whole exome sequencing of tumors from three GEMMs of lung adenocarcinoma driven by mutant EGFR, mutant Kras or by overexpression of MYC. Tumors from EGFR- and Kras- driven models exhibited respectively 0.02 and 0.07 non-synonymous mutations/megabase, a dramatically lower average mutational frequency than observed in human lung adenocarcinomas. Tumors from models driven by strong cancer drivers (mutant EGFR and Kras) harbored few mutations in known cancer genes, whereas tumors driven by MYC, a weaker initiating oncogene in the murine lung, acquired recurrent clonal oncogenic Kras mutations. In addition, although EGFR- and Kras- driven models both exhibited recurrent whole chromosome DNA copy number alterations, the specific chromosomes altered by gain or loss were different in each model. These data demonstrate that GEMM tumors exhibit relatively simple somatic genotypes compared to human cancers of a similar type, making these autochthonous model systems useful for additive engineering approaches to assess the potential of novel mutations on tumorigenesis, cancer progression, and drug sensitivity.

Cancer Biology↗