Natural antisense transcripts (NAT) and alternative polyadenylation (APA) of messenger RNA (mRNA) are important contributors of transcriptome complexity, each playing a critical role in multiple biological processes. However, whether they have crosstalk and function collaboratively is unclear. We discovered that APA enriched in human sense-antisense (S-AS) gene pairs, and finally focused on RNASEH2C-KAT5 S-AS pair for further study. In cis but not in trans over-expression of the antisense KAT5 gene promoted the usage of distal polyA (pA) site in sense gene RNASEH2C, which generated longer 3' untranslated region (3'UTR) and produced less protein, accompanying with slowed cell growth. Mechanistically, elevated Pol II occupancy coupled with SRSF3 could explain the higher usage of distal pA site. Finally, NAT-mediated downregulation of sense gene's protein level in RNASEH2C-KAT5 pair was specific for human rather than mouse, which lacks the distal pA site of RNASEH2C. We provided the first evidence to support that certain gene affected phenotype may not by the protein of its own, but by affecting the expression of its overlapped gene through APA, implying an unexpected view for understanding the link between genotype and phenotype.
Cell Proliferation ; genetics ; Evolution, Molecular ; Gene Expression Regulation ; genetics ; HEK293 Cells ; Humans ; Polyadenylation ; genetics ; RNA, Antisense ; genetics ; RNA, Messenger ; genetics ; Ribonuclease H ; genetics ; Serine-Arginine Splicing Factors ; metabolism ; Transcription, Genetic ; Up-Regulation ; genetics

Varying length of messenger RNA (mRNA) 3′-untranslated region is generated by alternating the usage of polyadenylation sites during pre-mRNA processing. It is prevalent through all eukaryotes and has emerged as a key mechanism for controlling gene expression. Alternative polyadenylation (APA) plays an important role for cell growth, proliferation, and differentiation. In this review, we discuss the functions of APA related with various physiological conditions including cellular metabolism, mRNA processing, and protein diversity in a variety of disease models. We also discuss the molecular mechanisms underlying APA regulation, such as variations in the concentration of mRNA processing factors and RNA-binding proteins, as well as global transcriptome changes under cellular signaling pathway.
Eukaryota ; Gene Expression ; Humans* ; Metabolism ; Polyadenylation* ; RNA Precursors ; RNA, Messenger ; RNA-Binding Proteins ; TOR Serine-Threonine Kinases ; Transcriptome

BACKGROUNDSurvivin is an oncoprotein silenced in normal mature tissues but reactivated in serous ovarian cancer (SOC). Although transcriptional activation is assumed for its overexpression, the long 3'-untranslated region (3'-UTR) in survivin gene, which contains many alternate polyadenylation (APA) sites, implies a propensity for posttranscriptional control and therefore was the aim of our study.

METHODSThe abundance of the coding region, the proximal and the distal region of survivin mRNA 3'-UTR, was evaluated by real-time polymerase chain reaction (PCR) in SOC samples, cell lines, and normal fallopian tube (NFT) tissues. The APA sites were confirmed by rapid amplification of cDNA 3' ends and DNA sequencing. Real-time PCR were used to screen survivin-targeting microRNAs (miRNAs) that were inversely correlated with survivin. The expression of an inversely correlated miRNA was restored by pre-miRNA transfection or induction with a genotoxic agent to test its inhibitory effect on survivin overexpression.

RESULTSVarying degrees of APA were observed in SOC by comparing the abundance of the proximal and the distal region of survivin 3'-UTR, and changes of 3'-UTR correlated significantly with survivin expression (r = 0.708, P< 0.01). The main APA sites are proved at 1197 and 1673 of survivin 3'-UTR by DNA sequencing. Higher level of 3'-UTR proximal region than coding region was observed in NFT, as well as in SOC and cell lines. Among the survivin-targeting miRNAs, only a few highly expressed miRNAs were inversely correlated with survivin levels, and they mainly targeted the distal part of the 3'-UTR. However, in ovarian cancer cells, restoration of an inversely correlated miRNA (miR-34c) showed little effect on survivin expression.

CONCLUSIONSIn NFT tissues, survivin is not transcriptionally silenced but regulate posttranscriptionally. In SOC, aberrant APA leads to the shortening of survivin 3'-UTR which enables it to escape the negative regulation of miRNAs and is responsible for survivin up-regulation.

3' Untranslated Regions ; genetics ; Female ; Humans ; Inhibitor of Apoptosis Proteins ; genetics ; metabolism ; MicroRNAs ; genetics ; Ovarian Neoplasms ; genetics ; metabolism ; Polyadenylation ; Real-Time Polymerase Chain Reaction

OBJECTIVETo perform a genome-wide alternative polyadenylation (APA) profiling in both mouse female germline stem cells (FGSCs) and embryonic stem cells (ESCs) and explore the role of germline-specific APA in the biological behaviors of FGSCs.

METHODSWe used a high-throughput sequencing-based method 3T-Seq to profile the genome-wide 3' termini of the transcripts and delineate all the APA sites in mouse FGSCs and ESCs. The genes with altered APA sites in FGSCs compared with ESCs were analyzed with DAVID Gene Ontology tool for their biological roles.

RESULTSWe identified a total of 50243 APA sites in 16973 genes. In FGSCs, 1148 genes were shown to have alterations in 3'UTR length, among which 795 ( 66%) genes had shortened and 353 (34%) had lengthened 3'UTR. Some of the genes with shortened 3'UTR were involved in germ cell development.

CONCLUSIONSOur genome-wide APA profiling analysis reveals a cell type-specific APA alternation in FGSCs, and APA-mediated 3'UTR alteration contributes to germline-related biological process. This study provides a framework for understanding the post-transcriptional regulation mechanisms in FGSCs.

3' Untranslated Regions ; Animals ; Cell Differentiation ; Embryonic Germ Cells ; metabolism ; Embryonic Stem Cells ; metabolism ; Female ; Gene Expression Regulation ; Genome ; Mice ; Polyadenylation

OBJECTIVETo analyze the alteration in alternative polyadenylation (APA) sites of tumor-related genes in gastric cancer cells.

METHODSWe used 3'RACE to capture the APA sites of two tumor-related genes (HSP90α and SEC11A) in gastric cancer cell lines MKN45, MKN28 and AGS, and compared the results with annotated poly(A) sites in UCSC database.

RESULTSWe found new APA sites in the two tumor-related genes in gastric cancer cells to produce new mRNA isoforms with different 3'UTRs.

CONCLUSIONSThere are new mRNA isoforms of HSP90α and SEC11A derived from ATA in gastric cancer cells, which provides new insights into the mechanisms of gastric tumorigenesis.

Cell Line, Tumor ; Cell Transformation, Neoplastic ; Genes, Neoplasm ; Humans ; Polyadenylation ; Stomach Neoplasms ; genetics

Adult ; Benzamides ; pharmacology ; Humans ; Hypereosinophilic Syndrome ; drug therapy ; genetics ; Imatinib Mesylate ; Male ; Mutation ; Oncogene Proteins, Fusion ; Piperazines ; pharmacology ; Pyrimidines ; pharmacology ; Receptor, Platelet-Derived Growth Factor alpha ; genetics ; mRNA Cleavage and Polyadenylation Factors

The aim of study is to explore the characteristics of cytogenetics and molecular biology in patients with eosinophilia. Bone marrow samples from 79 cases of eosinophilia (AEoC ≥ 1.5×10(9)/L) were detected for PDGFRA/B and FGFR1 gene rearrangement by fluorescence in situ hybridization and reverse transcription polymerase chain reaction (RT-PCR). Forty-four samples were detected for T cell receptor (TCR) clonal rearrangement by PCR. The results showed that among 76 cases the FIP1L1/PDGFRA (F/P) fusion gene was detected in 19 cases, the CHIC2 deletion was detected in 19 cases, the PDGFRA rearrangement was detected in 4 cases, and no FIP1L1 rearrangement was detected. According to the 2008 WHO classification, diagnosis were revised as myeloid neoplasms with PDGFRA/B rearrangement in 20 (42%) of 48 patients and 5 (83%) of 6 patients with hypereosinophilia syndrome (HES) or chronic eosinophilic leukemia (CEL), respectively. The diagnosis in (17%) of 6 patients with CEL was revised as chronic eosinophilic leukemia, not otherwise as specified (CEL-NOS). Clonal cytogenetic abnormalities were detected in 1 case of CEL-NOS and 3 cases with PDGFRB rearrangement. Karyotypic abnormalities involved in chromosome 4q12 were not detected in all of the 21 cases with PDGFRA rearrangement. The clonal TCR gene rearrangement were detected in 33% (5/15), 40% (6/15), and 36% (5/14) cases with PDGFRA/B rearrangement, HES, or secondary eosinophilia, respectively. There was no statistical difference in incidence rate among 3 subgroups. It is concluded that PDGFRA/B rearrangement can be detected in many cases of HES or CEL. Interphase FISH and PCR testing can enhance the diagnostic rate of myeloid neoplasms with PDGFRA/B rearrangement.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Female ; Gene Rearrangement ; Humans ; Hypereosinophilic Syndrome ; genetics ; In Situ Hybridization, Fluorescence ; Karyotyping ; Male ; Middle Aged ; Oncogene Proteins, Fusion ; genetics ; Receptor, Fibroblast Growth Factor, Type 1 ; genetics ; Receptor, Platelet-Derived Growth Factor alpha ; genetics ; Receptor, Platelet-Derived Growth Factor beta ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Young Adult ; mRNA Cleavage and Polyadenylation Factors ; genetics

The cytoplasmic polyadenylation element (CPE)-binding protein (CPEB) binds to CPE containing mRNAs on their 3' untranslated regions (3'UTRs). This RNA binding protein comes out many important tasks, especially in learning and memory, by modifying the translational efficiency of target mRNAs via poly (A) tailing. Overexpressed CPEB has been reported to induce the formation of stress granules (SGs), a sort of RNA granule in mammalian cell lines. RNA granule is considered to be a potentially important factor in learning and memory. However, there is no study about RNA granule in Aplysia. To examine whether an Aplysia CPEB, ApCPEB1, forms RNA granules, we overexpressed ApCPEB1-EGFP in Aplysia sensory neurons. Consistent with the localization of mammalian CPEB, overexpressed ApCPEB1 formed granular structures, and was colocalized with RNAs and another RNA binding protein, ApCPEB, showing that ApCPEB1 positive granules are RNA-protein complexes. In addition, ApCPEB1 has a high turnover rate in RNA granules which were mobile structures. Thus, our results indicate that overexpressed ApCPEB1 is incorporated into RNA granule which is a dynamic structure in Aplysia sensory neuron. We propose that ApCPEB1 granule might modulate translation, as other RNA granules do, and furthermore, influence memory.
Animals ; Aplysia/genetics/*metabolism ; Fluorescence Recovery After Photobleaching ; RNA/genetics/metabolism ; Sensory Receptor Cells/*metabolism ; mRNA Cleavage and Polyadenylation Factors/genetics/metabolism/*physiology

Influenza A/H1N1 virus-encoded nonstructural, or NS1, protein inhibits the 3'-end processing of cellular pre-mRNAs by binding the cellular protein: the 30-kDa subunit of CPSF (cleavage and polyadenylation specificity factor, CPSF30). CPSF30 binding site of the NS1 protein is a potential target for the development of drugs against influenza A/H1N1 virus. A yeast two-hybrid screening system was constructed and used for screening Chinese medicines that inhibit the interaction of the A/H1N1 flu NS1 protein and human CPSF30 protein. The NS1 gene of A/H1N1 virus was amplified by consecutive polymerase chain reaction (PCR), and the human CPSF30 gene of HeLa cell cloned by reverse transcriptase-polymerase chain reaction (RT-PCR). Then the two gene fragments confirmed by sequencing were subcloned into the yeast expression vectors pGBKT7 and pGADT7, respectively. The two constructs, bait vector pGBKNS1 and prey vector pGADCPSF, were co-transformed into yeast AH109. The eight individual yeast colonies were picked and subjected to verification by PCR/gel electrophoresis. The inhibition of the NS1-CPSF30 interaction was allowed the identification of selective inhibitors. The four of more than thirty identified Chinese medicines, including 'Shuanghuanglian oral liquid', showed the strong inhibition of the NS1-CPSF30 interaction.
Base Sequence ; Binding Sites ; Cleavage And Polyadenylation Specificity Factor ; genetics ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Gene Amplification ; HeLa Cells ; Humans ; Influenza A Virus, H1N1 Subtype ; genetics ; Peptide Fragments ; genetics ; Plasmids ; Protein Binding ; drug effects ; Transformation, Genetic ; Two-Hybrid System Techniques ; Viral Nonstructural Proteins ; genetics ; metabolism

BACKGROUND: Eosinophilia may be associated with various primary and reactive conditions. The incidence and the causes of eosinophilia might have been changed according to the changes in the incidence of diseases such as cancer, chronic degenerative diseases, etc. We have conducted a retrospective study to investigate the incidence and causes of eosinophilia. METHODS: Eosinophilia and hypereosinophilia were defined when absolute eosinophil count was greater than 500/microL and 1,500/microL, respectively. Patient's clinical records were reviewed to find out the underlying clinical conditions responsible for causes of hypereosinophilia. Conventional chromosomal analysis, reverse transcriptase PCR and FISH for gene rearrangement were performed to check the presence of clonal eosinophilia. RESULTS: Out of 41,137 patients who had a hematology profile performed, 5,019 (12.2%) and 373 patients (0.9%) were found to have eosinophilia and hypereosinophilia, respectively. Among patients with hypereosinophilia, 227 patients (60.9%) had identifiable and/or possible causes. The major causes of hypereosinophilia were malignancy (35.2%), allergy and skin diseases (18.1%), infectious diseases (15.4%), hepatobiliary diseases (7.5%), bone marrow clonal diseases (6.6%) and parasite infections (6.6%). We also found a rare case of FIP1L1-PDGFRalpha positive chronic eosinophilic leukemia combined with light chain multiple myeloma. CONCLUSIONS: We found a difference in the distribution of causes of hypereosinophilia in comparison with previous Korean studies, and the most common cause of hypereosinophilia in the current study was malignancy. A rare case of clonal eosinophilia (chronic eosinophilic leukemia) associated with multiple myeloma was confirmed using molecular studies.
Adolescent ; Adult ; Age Factors ; Aged ; Aged, 80 and over ; Bone Marrow/pathology ; Child ; Child, Preschool ; Eosinophilia/epidemiology/*etiology/genetics ; Female ; Hospitals, University ; Humans ; Hypereosinophilic Syndrome/epidemiology/*etiology/genetics ; Infant ; Infant, Newborn ; Male ; Middle Aged ; Receptor, Platelet-Derived Growth Factor alpha/genetics/metabolism ; Retrospective Studies ; Sex Factors ; Young Adult ; mRNA Cleavage and Polyadenylation Factors/genetics/metabolism