BACKGROUND & AIMS:We aimed to identify long noncoding RNAs (lncRNAs) that are up-regulated in gastric cancer tissues from patients and study their function in gastric tumor metastasis. METHODS: We collected gastric tumor and nontumor tissues from patients in China and analyzed levels of lncRNAs by microarray analysis, proteins by immunohistochemistry, and RNAs by quantitative reverse-transcription polymerase chain reaction; we compared these with survival times of patients and tumor progression. RNA levels were knocked down or knocked out in BGC-823, SGC-7901, and MKN45 cell lines using small interfering or short hairpin RNAs or clustered regularly interspaced short palindromic repeats (ie, CRISPR)/CRISPR associated protein 9 (ie, Cas9) vectors. Genes were overexpressed from transfected plasmids in HGC-27 cells. Cells were analyzed by Northern blot and immunoblot, polysome profiling assay, and cell invasion assay. Cells were injected into the tail veins or spleens of nude mice or SCID mice; lung and liver tissues were collected, and metastases were counted. lncRNAs were cloned by using rapid amplification of complementary DNA ends. Their interactions with other genes were determined by RNA pulldown and mapping assays. RESULTS: In microarray analyses, we identified 151 lncRNAs expressed at significantly higher levels in gastric tumor vs nontumor tissues. Levels of an lncRNA that we called gastric cancer metastasis associated long noncoding RNA (GMAN) were increased in gastric tumor tissues, compared with nontumor tissues; its up-regulation was associated with tumor metastasis and shorter survival times of patients. The GMAN gene overlaps with the ephrin A1 gene (EFNA1) and was highly expressed in BGC-823 and MKN45 cells. Knockdown of GMAN in these cells did not affect proliferation, colony formation, or adhesion but did reduce their invasive activity in Transwell assays. Ectopic expression of GMAN increased the invasive activity of HGC-27 cells. BGC-823 and MKN45 cells with knockdown of GMAN formed fewer metastases after injection into tail veins of nude mice. Knockdown or knockout of GMAN also reduced levels of ephrin A1 protein in cells. We found that GMAN promoted translation of ephrin A1 messenger RNA into protein by binding to the antisense GMAN RNA (GMAN-AS)-this antisense sequence is also complementary to that of ephrin A1 mRNA. Levels of ephrin A1 protein were also increased in gastric tumors from patients with metastases than in those without metastases. Knockout of ephrin A1 in BGC-823 cells reduced their invasive activity in Transwell assays and ability to form metastases after injection into SCID mice. Ectopic expression of ephrin A1 in BGC-823 cells with knockdown or knockout of GMAN restored their invasive activities and ability form metastases in nude or SCID mice. A CRISPR/Cas9-based strategy to disrupt the GMAN gene significantly reduced the numbers of metastases formed from SGC-7901 cells in mice. CONCLUSIONS: We identified an lncRNA, which we call GMAN, that is increased in gastric tumors from p...

Background: Sogatella furcifera is an important phloem sap-sucking and plant virus-transmitting migratory insect of rice. Because of its high reproductive potential, dispersal capability and transmission of plant viral diseases, S. furcifera causes considerable damage to rice grain production and has great economical and agricultural impacts. Comprehensive studies into ecological aspects and virus–host interactions of S. furcifera have been limited because of the lack of a well-assembled genome sequence. Findings: A total of 241.3 Gb of raw reads from the whole genome of S. furcifera were generated by Illumina sequencing using different combinations of mate-pair and paired-end libraries from 17 insert libraries ranging between 180 bp and 40 kbp. The final genome assembly (0.72 Gb), with average N50 contig size of 70.7 kb and scaffold N50 of 1.18 Mb, covers 98.6 % of the estimated genome size of S. furcifera. Genome annotation, assisted by eight different developmental stages (embryos, 1st-5th instar nymphs, 5-day-old adults and 10-day-old adults), generated 21 254 protein-coding genes, which captured 99.59 % (247/248) of core CEGMA genes and 91.7 % (2453/2675) of BUSCO genes. Conclusions: We report the first assembled and annotated whole genome sequence and transcriptome of S. furcifera. The assembled draft genome of S. furcifera will be a valuable resource for ecological and virus–host interaction studies of this pest.

Although epigenetic modulation is critical for a variety of cellular activities, its role in erythropoiesis remains poorly understood. Teneleven translocation (TET) molecules participate in methylcytosine (5mC) hydroxylation, which results in DNA demethylation in several biological processes. In this research, the role of TETs in erythropoiesis was investigated by using the zebrafish model, where three TET homologs were identified. These homologs share conserved structural domains with their mammalian counterparts. Zebrafish TETs mediate the conversion of 5mC to hydroxymethylcytosine (5hmC) in zebrafish embryos, and the deletion of TET2 inhibits erythropoiesis by suppressing the expression of the scl, gata-1, and cmyb genes. TET2-upregulated lineage-specific genes and erythropoiesis are closely associated with the occurrence of 5hmC and demethylation in the intermediate CpG promoters (ICPs) of scl, gata-1, cmyb, which frequently occur at specific regions or CpG sites of these ICPs. Moreover, TET2 regulates the formation and differentiation of erythroid progenitors, and deletion of TET2 leads to erythrocyte dysplasia and anemia. Here, we preliminarily proved that TET2 plays an essential role in erythrocyte development by regulating lineage-specific genes via DNA oxidative demethylation. This report is anticipated to broaden current information on hematopoiesis and pathogenesis of hematopoiesis-related diseases.

Gastric cancer (GC) is among the most lethal human malignancies, and the leading cause of GC mortality is metastasis. However, the precise mechanism of GC metastasis remains unclear. To screen key transcriptional factors (TFs) involved in GC metastasis, we performed bioinformatics analysis of The Cancer Genome Atlas database and found that Krüppel‐like factor 9 (KLF9) is a GC metastasis‐associated TF. KLF9 is significantly decreased in patients with GC with distant metastasis compared with those patients without distant metastasis. Ectopic expression of KLF9 evidently inhibited the migration and invasion capabilities of GC cells. Conversely, knockdown of KLF9 endowed GC cells with stronger invasive capacity. Moreover, tail intravenous injection confirmed that KLF9 strongly inhibits the lung metastasis process of GC in vivo. Mechanistically, chromatin immunoprecipitation coupled with high‐throughput sequencing data from Encyclopedia of DNA Elements revealed that KLF9 specifically binds to the promoter region of matrix metalloproteinase (MMP)28. Further quantitative real‐time PCR and dual‐luciferase assay indicated that KLF9 directly inhibited MMP28 transcription. Importantly, decreased invasion and metastasis capability of GC cells caused by ectopic KLF9 expression could be rescued via reinforcing MMP28 expression in vivo. Collectively, our study indicates that KLF9 significantly suppresses GC cell invasion and metastasis through inhibiting MMP28 transcription.—Li, Y., Sun, Q., Jiang, M., Li, S., Zhang, J., Xu, Z., Guo, D., Gu, T., Wang, B., Xiao, L., Zhou, T., Zhuo, W. KLF9 suppresses gastric cancer cell invasion and metastasis through transcriptional inhibition of MMP28. FASEB J. 33, 7915–7928 (2019). http://www.fasebj.org

Highlights d Drosophila antiviral lncRNA VINR accumulates because of DCV's viral suppressor of RNAi d VINR is necessary for induction of antimicrobial peptide genes but not antiviral RNAi d VINR prevents degradation of Cactin, which activates a noncanonical antimicrobial pathway d VINR-deficient flies exhibit enhanced susceptibility to both bacterial and DCV infection