Mitogenomic Phylogeny of Tonnoidea Suter, 1913 (1825) (Gastropoda: Caenogastropoda).

The Tonnoidea Suter, 1913 (1825) is a moderately diverse group of large predatory gastropods, the systematics of which remain unclear. In the present study, the complete mitochondrial genomes of nine Tonnoidean species were sequenced. All newly sequenced mitogenomes contain 13 protein-coding genes (PCGs), 22 transfer RNA genes and two ribosomal RNA genes, showing similar patterns in genome size, gene order and nucleotide composition. The ratio of nonsynonymous to synonymous of PCGs indicated that NADH complex genes of Tonnoideans were experiencing a more relaxed purifying selection compared with the COX genes. The reconstructed phylogeny based on the combined amino acid sequences of 13 protein-coding genes and the nucleotide sequences of two rRNA genes supported that Ficidae Meek, 1864 (1840) is a sister to Tonnoidea. The monophylies of all Tonnoidean families were recovered and the internal phylogenetic relationships were consistent with the current classification. The phylogeny also revealed that Tutufa rebuta (Linnaeus, 1758) is composed of at least two different species, indicating that the species diversity within Bursidae Thiele, 1925 might be underestimated. The present study contributes to the understanding of the Tonnoidean systematics, and it could provide important information for the revision of Tonnoidean systematics in the future.

The complete mitochondrial genome of Hyotissasinensis (Bivalvia, Ostreoidea) indicates the genetic diversity within Gryphaeidae.

Different from the true oyster (family Ostreidae), the molecular diversity of the gryphaeid oyster (family Gryphaeidae) has never been sufficiently investigated. In the present study, the complete mitochondrial (mt) genome of Hyotissasinensis was sequenced and compared with those of other ostreoids. The total length of H.sinensis mtDNA is 30,385 bp, encoding 12 protein-coding-genes (PCGs), 26 transfer RNA (tRNA) genes and two ribosomal RNA (rRNA) genes. The nucleotide composition and codon usage preference of H.sinensis mtDNA is similar to that of H.hyotis within the same genus. On the other hand, the presence of three trnM and three trnL genes of H.sinensis was not detected neither in H.hyotis nor other ostroid species. Another unique character of H.sinensis mtDNA is that both rrnS and rrnL have a nearly identical duplication. The PCG order of H.sinensis is identical to H.hyotis and the two congener species also share an identical block of 12 tRNA genes. The tRNA rearrangements mostly happen in the region from Cox1 to Nad3, the same area where the duplicated genes are located. The rearrangements within Gryphaeidae could be explained by a "repeat-random loss model". Phylogenetic analyses revealed Gryphaeidae formed by H.sinensis + H.hyotis as sister to Ostreidae, whereas the phylogenetic relationship within the latter group remains unresolved. The present study indicated the mitogenomic diversity within Gryphaeidae and could also provide important data for future better understanding the gene order rearrangements within superfamily Ostreoidea.

Protective functions of salvianolic acid B in PC-12 cells against hydrogen peroxide-triggered damage by mediation of microRNA-26a.

Spinal cord injury (SCI) can lead to varying degrees of sensory and motor dysfunction. Salvianolic acid B (Sal-B) is the dominating bioactive constituent of Danshen, which has been reported to alleviate liver fibrosis and exert neuroprotective effects. But, the influence of Sal-B in SCI remains mysterious. The research planned to delve the protective function of Sal-B in hydrogen peroxide (H2O2)-caused PC-12 cell injury. H2O2-caused PC-12 cells injury model was built, CCK-8, Transwell and flow cytometry experiments were enforced to assess cell proliferation, migration and apoptosis. The microRNA (miR)-26a plasmid and the matching control were transfected into PC-12 cells, subsequently, the influence of miR-26a inhibition in H2O2-corrupted PC-12 cells was evaluated. The cell growth-correlated factors and PI3K/AKT and MEK/ERK pathways were assayed through western blot assay. Results corroborated that Sal-B eased H2O2-evoked injury in PC-12 cells. Ascended miR-26a was monitored in Sal-B and H2O2-exposed cells. MiR-26a inhibition annulled the protective action of Sal-B in H2O2-corrupted cells. The protective function of Sal-B was enabled through activating PI3K/AKT and MEK/ERK pathways. These findings delineated that Sal-B protected PC-12 cells against H2O2-caused injury through ascending miR-26a via initiating PI3K/AKT and MEK/ERK pathways. Highlights H2O2 causes PC-12 cell injury; Sal-B eases H2O2-caused PC-12 cell injury; Sal-B protects PC-12 cells against H2O2-caused injury via elevating miR-26a; Sal-B activates AKT and MEK/ERK pathways via modulating miR-26a.

Tip60-dependent acetylation of KDM2B promotes osteosarcoma carcinogenesis.

Overexpression of KDM2B is frequently occurred in various human solid tumours, and the high levels of KDM2B are associated with tumourigenesis. However, whether and how its activities might be modulated to facilitate tumour progression is still unclear. Immunoprecipitation and immunoblotting were carried out to detect the acetylation of KDM2B. Nucleosomes and mononucleosomes were prepared and the demethylation activity of KDM2B was detected in these two substrates. The effects of KDM2B acetylation on the transcription of target genes, as well as tumour growth and metastasis were then studied. KDM2B was acetylated in osteosarcoma cancer cell lines (MG-63 and HOS). This modification occurred at lysine 758 and catalysed by Tip60. Acetylation of KDM2B decreased the capacity of KDM2B in binding with nucleosomes. KDM2B acetylation diminished its demethylation activity towards nucleosomal substrates rather than towards bulk histone. Besides, acetylation of KDM2B diminished its ability to bind with the promoters of p21 and puma. Moreover, the promoting effects of KDM2B acetylation on tumour cells' proliferation and metastasis, and in vivo tumour growth were dependent on Tip60. KDM2B is acetylated at lysine 758 by Tip60 in human osteosarcoma cells. Acetylation of KDM2B diminishes its association with nucleosomes, and thus increasing methylation of H3K36 at its target genes as well as enhancing its oncogenic effects.