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Biology subjects

Liu, S.-R.

Publications and source records attributed to Liu, S.-R..

2 recordsLinked to original sources

CREB1 contributes colorectal cancer cell plasticity by regulating lncRNA CCAT1 and NF-κB pathways

The CREB1 gene encodes a pleiotropic transcription factor that frequently dysregulated in cancers. CREB1 can regulates tumour cell status of proliferation or migration, however, the molecular basis for this switch involvement in cell plasticity has not been fully understood. Here, we show that knocking out CREB1 triggered a remarkable effect of epithelial-mesenchymal transition (EMT) and led to the occurrence of inhibited proliferation and enhanced motility in cancer cells. Mechanistically, CREB1-knockout cells showed arrest in the G0/G1 phase as a result of impaired CREB1-dependent transcription of CCAT1 and E2F1. Interestingly, the competition between the coactivator CBP/p300 for CREB1 and p65 leads to the activation of the NF-{kappa}B pathway in cells with CREB1 disrupted, which induces an EMT phenotype and enhances motility. These studies identified previously unknown mechanisms of CREB1 in cell plasticity via its lncRNA and protein effector pathways, revealing an important feature that should be considered in CREB1-targeted tumour therapies.

cell biology↗

Discovering the Interactions between Circular RNAs and RNA-binding Proteins from CLIP-seq Data using circScan

Although tens of thousands of circular RNAs (circRNAs) have been identified in mammalian genomes, only few of them have been characterized with biological functions. Here, we report a new approach, circScan, to identify regulatory interactions between circRNAs and RNA-binding proteins (RBPs) by discovering back-splicing reads from Cross-Linking and Immunoprecipitation followed by high-throughput sequencing (CLIP-seq) data. By using our method, we have systematically scanned ~1500 CLIP-seq datasets, and identified ~12540 and ~1090 novel circRNA-RBP interactions in human and mouse genomes, respectively, which include all known interactions between circRNAs and Argonaute (AGO) proteins. More than twenty novel interactions were further experimentally confirmed by RNA Immunoprecipitation quantitative PCR (RIP-qPCR). Importantly, we uncovered that some natural circRNAs interacted with cap-independent translation factors eukaryotic initiation factor 3 (eIF3) and N6-Methyladenosine (m6A), indicating they can be translated into proteins. These findings demonstrate that circRNAs are regulated by various RBPs, suggesting they may play important roles in diverse biological processes.

molecular biology↗