Project description:We have identified Alyref and Gabpb1 as developmentally important genes by siRNA screening. Gene knockout (KO) of Alyref and Gabpb1 by the CRISPR/Cas9 system resulted in early developmental arrest in mice. To gain mechanistic insight into the developmental role of Alyref and Gabpb1, we performed RNA sequencing (RNA-seq) analysis of the KO embryos.
Project description:The TREX complex (TREX) plays key roles in nuclear export of mRNAs. However, little is known about its transcriptome-wide binding targets. We used individual cross-linking and immunoprecipitation (iCLIP) to identify the binding sites of ALYREF, an mRNA export adaptor in TREX, in human cells. As expected, iCLIP reads are mainly mapped to exons of mRNAs. Globally, ALYREF binding shows two apparent enrichments on the mRNA, one is near the 5’ end and the other is very close to the 3’ end. In addition, numerous middle exons harbor ALYREF binding sites. CBP80 and PABPN1 mainly affect ALYREF binding at the 5’ and the 3’ region, respectively. Interestingly, we found that the 3’ processing factor CstF64 directly interacts with ALYREF and is required for the overall binding of ALYREF on the mRNA. Sequence analysis led to the identification of multiple
Project description:The RNA methyltransferase Aly/REF export factor (ALYREF) is considered one type of “reader” protein located in the nucleus that recognizes and binds directly with m5C sites in RNA and facilitates the export of RNA from the nucleus to the cytoplasm. Notably, ALYREF is considered a promising target for diagnosis and prognosis prediction. However, until now, the low number of related studies has limited the understanding of the mechanism of the HCC-promoting effects of ALYREF. To further elucidate the oncogenic roles of ALYREF in hepatocellular carcinoma (HCC), we assessed the expression levels of ALYREF in clinical samples and HCC cell lines and explored the effects of ALYREF deficiency by both in vitro experiments and m5C-methylated RNA immunoprecipitation sequencing (m5C-MeRIP-Seq)
Project description:we try to investigate the binding of ALYREF and NXF1 on histone mRNA when the cell treated with indicated siRNAs. ALYREF plays key roles in nuclear export of polyadenylated mRNAs and also modulates their 3' processing, but whether it is involved in regulating RNAs beyond polyadenylated mRNAs is unknown. The replication-dependent (RD) histone mRNAs are not polyadenylated, but end in a stem-loop (SL) structure. Here we demonstrate that ALYREF prevalently binds a region next to the SL on RD histone mRNAs. SL-binding protein (SLBP) directly interacts with ALYREF and ensures this binding. To examine how SLBP KD impact ALYREF distribution on the histone mRNA, we carried out ALYREF iCLIP in control and SLBP KD cells. To investigate the functional consequence for ALYREF binding on histone mRNAs, we isolated polyA+ and polyA- RNAs from control and ALYREF KD cells, and carried out RNA-seq separately.
Project description:DDX6 is an RNA helicase and involved in various post-transcriptional regulatory processes. Although DDX6 is an evolutionarily well conserved central player in post-transcriptional gene regulation, its function in embryonic development remains obscure. To study this, we examined Ddx6 knockout mouse embryos and pluripotent cell lines. E8.5 Ddx6 mutants exhibited gastrulation defects. To transcriptomically identify the existing cell population in E8.5 mutant embryos and further find the possible causes of this defect, we performed RNA-seq analysis with E8.5 embryo cDNA libraries.