lncRNA TUSC7 sponges miR-10a-5p and inhibits BDNF/ERK pathway to suppress glioma cell proliferation and migration.

OBJECTIVE: Gliomas as primary cerebral malignancies frequently occurring in adults have relatively high morbidity and mortality. The underlying role of long non-coding ribonucleic acids (lncRNAs) in malignancies has attracted much attention, among which tumor suppressor candidate 7 (TUSC7) is a novel tumor suppressor gene whose regulatory mechanism in human cerebral gliomas remains inconclusive. METHODS AND RESULTS: In this study, bioinformatics analysis indicated that TUSC7 could specifically bind to microRNA (miR)-10a-5p, and according to quantitative polymerase chain reaction (q-PCR), miR-10a-5p was up-regulated in human glioma cells and negatively correlated with TUSC7 expression. Dual-luciferase reporter gene assay showed the ability of TUSC7 to bind to miR-10a-5p, and overexpression of TUSC7 notably inhibited miR-10a-5p expression, restrained human glioma cell proliferation and migration, and regulated cell cycle and cyclin expression via the brain-derived neurotrophic factor/extracellular signal-regulated kinase (BDNF/ERK) pathway. The inhibitory effect of TUSC7 on miR-10a-5p was also verified by designing miR-10a-5p overexpression and knockdown panels for wound healing, Transwell and Western blotting assays. CONCLUSIONS: TUSC7 suppresses human glioma cell proliferation and migration by negatively modulating miR-10a-5p and inhibiting the BDNF/ERK pathway, thus acting as a tumor suppressor gene in human gliomas.

Inbreeding in Chinese Fir: Insight into the Rare Self-Fertilizing Event from a Genetic View.

Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) is a fast-growing conifer with great forestation value and prefers outcrossing with high inbreeding depression effect. Previously, we captured a special Chinese fir parent clone named as 'cx569' that lacks early inbreeding depression. In view of the fact that very little has been published about the rare self-fertilizing event in Chinese fir from a genetic view, herein, we conduct an SSR-based study on the variation of open- and self-pollinated offspring of this parent to gain a view of the rare self-fertilizing event. The results indicated that genetic diversity of self-pollinated offspring was significantly reduced by half (Ho: 0.302, vs. 0.595, p = 0.001; He: 0.274 vs. 0.512, p = 0.002) when compared to an open-pollinated set. Self-pollinated offspring also had significantly positive FIS values (FIS = 0.057, p = 0.034) with a much higher proportion of common allele (20.59% vs. 0), reflecting their heterozygote deficiency. Clustering analysis further indicated a separation of the self- and opened- pollinated groups, implying a natural preference of outcrossing for cx569. However, the cx569 still had 6% acceptance for selfing. When accepted 100% for its own pollen, the cx569 led to a genetically unique selfing group. Additionally, this selfing group seemed to be consistently homozygous at seven particular loci. These findings gave us more genetic clues to gain insight into the rare self-fertilizing event in conifer (Chinese fir).

Further Mining and Characterization of miRNA Resource in Chinese Fir (Cunninghamia lanceolata).

In this study, we aimed to expand the current miRNA data bank of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) regarding its potential value for further genetic and genomic use in this species. High-throughput small RNA sequencing successfully captured 140 miRNAs from a Chinese fir selfing family harboring vigor and depressed progeny. Strikingly, 75.7% (n = 106) of these miRNAs have not been documented previously, and most (n = 105) of them belong to the novel set with 6858 putative target genes. The new datasets were then integrated with the previous information to gain insight into miRNA genetic architecture in Chinese fir. Collectively, a relatively high proportion (62%, n = 110) of novel miRNAs were found. Furthermore, we identified one MIR536 family that has not been previously documented in this species and four overlapped miRNA families (MIR159, MIR164, MIR171_1, and MIR396) from new datasets. Regarding the stability, we calculated the secondary structure free energy and found a relatively low R2 value (R2 < 0.22) between low minimal folding free energy (MFE) of pre-miRNAs and MFE of its corresponding mature miRNAs in most datasets. When in view of the conservation aspect, the phylogenetic trees showed that MIR536 and MIR159 sequences were highly conserved in gymnosperms.