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The aim of this study was to provide a reference for the riparian zone with protection and ecological restoration by analyzing the differences in typical vegetation ( Phragmites communis, Populus tomentosa , Salix sungkianica , and Carex schmidtii ) rhizosphere bacterial communities and their functions and identifying the potential of different types of vegetation to restore the damaged riparian zone in Songhua River. The 16S rRNA of rhizosphere soil bacteria in the four typical vegetation types of the riparian zone along the downstream of the Songhua River was sequenced using the Illumina MiSeq PE300 high-throughput sequencing platform. The community diversity, functional differences, and influencing factors of rhizosphere soil bacteria for different vegetation types were analyzed. The results showed that the Ace index, Chao1 index, and Shannon index of soil bacterial diversity in P.communis were significantly higher than those of P.tomentosa ( P <0.05), and there was no significant difference between the above two types of vegetation and S. sungkianica and C.schmidtii . There were significant differences between the soil bacterial community structure of P. tomentosa and that of the three other vegetation types ( P <0.05). The soil bacterial community structures of S.sungkianica, C.schmidtii , and P.communis were similar. Bacteria in the rhizosphere soil of the four typical vegetation types could be divided into 38 phyla. Acidobacteria, Actinobacteria, Chloroflexi, Verrucomicrobia, and Proteobacteria were the dominant phyla (relative abundance>5%), and the Nitrospirae, Gemmatimonadetes, Bacteroidetes, Firmicutes, and Rokubacteria of bacteria had a relative abundance greater than 1%. The bacterial community in the rhizosphere soil of the four typical vegetation types had 6 primary metabolic pathways and 43 secondary metabolic pathways, including 14 types of main secondary metabolic pathways (relative abundance>1%). Diversity in rhizosphere soil bacterial communities of different vegetation types was significantly influenced by the C/N ratio, soil pH, and moisture content. Hence, the effects of different vegetation types in repairing the degraded riparian zone were different, and wetland vegetation ( S.sungkianica and C.schmidtii ) was conducive to the improvement in soil bacterial diversity and soil ecosystem functions.

Pseudomonas plecoglossicida is a rod-shaped, gram-negative bacterium with flagella. It causes visceral white spot disease and high mortality in Larimichthys crocea during culture, resulting in serious economic loss. Analysis of transcriptome and quantitative real-time polymerase chain reaction (PCR) data showed that dksA gene expression was significantly up-regulated after 48 h of infection with Epinephelus coioides (log 2 FC=3.12, P <0.001). RNAi of five shRNAs significantly reduced the expression of dksA in P. plecoglossicida , and the optimal silencing efficiency was 96.23%. Compared with wild-type strains, the symptoms of visceral white spot disease in L. crocea infected with RNAi strains were reduced, with time of death delayed by 48 h and mortality reduced by 25%. The dksA silencing led to a substantial down-regulation in cellular component-, flagellum-, and ribosome assembly-related genes in P. plecoglossicida , and the significant up-regulation of fliC may be a way in which virulence is maintained in P. plecoglossicida . The GO and KEGG results showed that RNAi strain infection in L. crocea led to the down-regulation of inflammatory factor genes in immune-related pathways, which were associated with multiple immune response processes. Results also showed that dksA was a virulence gene in P. plecoglossicida . Compared with the wild-type strains, RNAi strain infection induced a weaker immune response in L. crocea .

Transcriptional factor FOXC1 has been demonstrated to play a key role in embryogenesis in animal studies and may participate in tumorigenesis. However, the specific function of this gene in ovarian tumors has not been fully determined. In this study, potential correlations between FOXC1 expression and clinicopathological features of serous ovarian tumors were investigated. FOXC1 expression was analyzed in SKOV-3 and HO-8910 cell lines and serous ovarian tumor tissues. A significant correlation was observed between FOXC1 protein expression and pathological subtype as well as FIGO stage (P<0.05) in serous ovarian tumors in our retrospective study. No significant association was revealed between FOXC1 protein expression and the clinicopathological factors of age, histological grade and volume of ascites (P>0.05). The results suggest that high expression of FOXC1 protein may serve as a marker for benign serous ovarian tumors and a suggest a trend towards good prognosis.