Project description:We report that retention of intron 2 which affects expression of CD19 in CART-19 relapsed leukemia occurs in the context of full length CD19 transcript using Oxford Nanopore sequencing technology. By performing Direct RNA sequencing on Reh leukemia cell lines, we showed that intron 2 retention is functionally equivalent to nonsense mutations.
Project description:Analysis of high-throughput transcriptome sequencing (RNA-seq) data often observed numerous 'non-co-linear' (NCL) transcripts, which may originate from genetic rearrangements (gene fusion) indicated the importance of fusion events and circRNAs in carcinogenesis; however, the role of ts-RNAs remains largely uninvestigated. Here we developed a hybrid sequencing pipeline ("NCLscan-hybrid"), which integrated different types of short (Illumina-based) and extra-long (PacBio-based) RNA-seq data to eliminate potential false positives from experimental artifacts, fusion events, and circRNAs. We applied NCLscan-hybrid to investigate of ts-RNAs in human breast cancer, the most malignant tumors diagnosed in women worldwide. Through multiple experimental validation steps, we confirmed that the intragenic ts-RNA, ts-ARFGEF1, was highly expressed in breast cancer cells but absent in normal breast cells. Furthermore, we experimentally validated that ts-ARGEF1 can contribute to cell proliferation and apoptosis. Analysis of xenograft in nude mice showed that disruption of ts-ARFGEF1 expression can significantly attenuate tumor growth. Microarray analysis revealed that ts-ARFGEF1 knockdown could trigger PERK/ATF4/CHOP signaling pathway, implying the function of ts-ARFGEF1 in ER homeostasis. Taken together, our findings provide an in-depth view of the true complexity of intragenic NCL events and, for the first time, show further insight into the potential roles of intragenic ts-RNAs in tumor cell development.
Project description:Results indicate that CRISPR/Cas9 gene editing of a suboptimal E19/I19 5′ splice site in the TOP2α gene results in circumvention of acquired drug resistance to etoposide and other TOP2-targeted drugs in a clonal K562 cell line by enhancing removal of intron 19 thereby decreasing formation of a truncated TOP2α/90 isoform and increasing expression of full-length TOP2α/170 in these resistant cells.
Project description:we applied RNA-seq to detect novel expressed transcripts in 12 tissues of giant pandas, using a transcriptome reconstruction strategy combining reference-based and de novo methods. Then we used mass spectrometry method to identify proteomes of five selected tissues, aiming at validating these novel full-length genes we identified.