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Background. Gastric cancer (GC) is a malignant tumour that originates in the gastric mucosal epithelium and is associated with high mortality rates worldwide. Long noncoding RNAs (lncRNAs) have been identified to play an important role in the development of various tumours, including GC. Yet, lncRNA biomarkers in a competing endogenous RNA network (ceRNA network) that are used to predict survival prognosis remain lacking. The aim of this study was to construct a ceRNA network and identify the lncRNA signature as prognostic factors for survival prediction. Methods. The lncRNAs with overall survival significance were used to construct the ceRNA network. Function enrichment, protein-protein interaction, and cluster analysis were performed for dysregulated mRNAs. Multivariate Cox proportional hazards regression was performed to screen the potential prognostic lncRNAs. RT-qPCR was used to measure the relative expression levels of lncRNAs in cell lines. CCK8 assay was used to assess the proliferation of GC cells transfected with sh-lncRNAs. Results. Differentially expressed genes were identified including 585 lncRNAs, 144 miRNAs, and 2794 mRNAs. The ceRNA network was constructed using 35 DElncRNAs associated with overall survival of GC patients. Functional analysis revealed that these dysregulated mRNAs were enriched in cancer-related pathways, including TGF-beta, Rap 1, calcium, and the cGMP-PKG signalling pathway. A multivariate Cox regression analysis and cumulative risk score suggested that two of those lncRNAs (LINC01644 and LINC01697) had significant prognostic value. Furthermore, the results indicate that LINC01644 and LINC01697 were upregulated in GC cells. Knockdown of LINC01644 or LINC01697 suppressed the proliferation of GC cells. Conclusions. The authors identified 2-lncRNA signature in ceRNA regulatory network as prognostic biomarkers for the prediction of GC patient survival and revealed that silencing LINC01644 or LINC01697 inhibited the proliferation of GC cells.

A homologue of FLORICAULA/LFY, designated StLEAFY (accession number EF062357), was isolated from potato by reverse transcriptase-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends. The complementary DNA (cDNA) sequence of StLFY was 1,417 bp long and contained an open reading frame of 1,257 bp. Its corresponding genomic sequence (EU371047) showed that the StLFY gene contained three exons and two introns. The predicted amino acid sequence of the gene consisted of 418 amino acids and had a conserved region in the C-terminal when being aligned with sequences of other LFY homologues. The StLFY protein had a high identity with LFY homologous members from other species. Analysis of StLFY expression at the mRNA level by RT-PCR showed that it was slightly expressed in the apical buds, floral buds, and initial stolons.

A full-length cDNA of a StCONSTANS-like (StCOL) gene was cloned from potato (Solanum tuberosum L.) by RT-PCR and RACE. The predicted amino acid sequence of this cDNA has a high degree of identity with other homologous members of the CO or COL family. Analysis of mRNA levels for StCOL shows that it is highly expressed in leaves and becomes weaker during tuberization; moreover, is independent of gibberellin A(3) and sucrose.