Expression pattern of MMP-12 in long-term optic nerve regeneration induced by lens injury / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the expression changes of MMP-12 during the long-term axon regeneration induced by the lens injury after the optic nerve clamp trauma in sprague-dawley(SD)rats.METHODS: The optic nerve injury model and lens injury model of SD rats were established, and the 24 experimental animals were divided into control group; lens injury group; optic nerve injury group; lens injury combined with optic nerve injury group, with 6 rats in each group. Reference transcriptome sequencing was used to analyze the expression changes of differentially expressed genes in the injured optic nerve region, and relevant differentially expressed genes with high expression were screened. Quantitative real-time polymerase chain reaction(qRT-PCR)and enzyme-linked immunosorbent assay(ELISA)were used to quantify the expression changes of matrix metalloproteinase-12(MMP-12)in the injured optic nerve region.RESULTS: The Principal Component Analysis of transcriptome sequencing indicated that lens injury combined with optic nerve injury was the principal component of gene expression change. Analysis of gene expression differences showed that the expression of MMP-12 gene was up-regulated in the lens injury combined with optic nerve injury group. The mRNA expression level of MMP-12 in the lens injury combined optic nerve injury group was up-regulated compared with the control group, the optic nerve injury group and the lens injury group at 14d and 21d after successful modeling(P<0.05). At 7, 28d, there was no difference in expression among all groups. The protein expression level of MMP-12 in the lens injury combined with optic nerve injury group was up-regulated compared with the control group and optic nerve injury group at 7, 14 and 21d after successful modeling(P<0.05), and it was up-regulated in the lens injury group combined with optic nerve injury group compared with optic nerve injury group at 21d(P<0.05). At 28d, there was no difference in expression among all groups.CONCLUSION: The up-regulated expression of MMP-12 may be involved in the long-term regeneration of the optic nerve after lens injury.

Draft genomes and reference transcriptomes extend the coding potential of the fish pathogen Piscirickettsia salmonis

Background: Draft and complete genome sequences from bacteria are key tools to understand genetic determinants involved in pathogenesis in several disease models. Piscirickettsia salmonis is a Gram-negative bacterium responsible for the Salmon Rickettsial Syndrome (SRS), a bacterial disease that threatens the sustainability of the Chilean salmon industry. In previous reports, complete and draft genome sequences have been generated and annotated. However, the lack of transcriptome data underestimates the genetic potential, does not provide information about transcriptional units and contributes to disseminate annotation errors. Results: Here we present the draft genome and transcriptome sequences of four P. salmonis strains. We have identified the transcriptional architecture of previously characterized virulence factors and trait-specific genes associated to cation uptake, metal efflux, antibiotic resistance, secretion systems and other virulence factors. Conclusions: This data has provided a refined genome annotation and also new insights on the transcriptional structures and coding potential of this fish pathogen.