Project description:Purpose: We compared the levels of miRNA specific for DEGs in isograft corneas with those in normal corneas, as well as the levels of miRNA specific for DEGs in allograft corneas with those in isograft corneas, to gain a better understanding of molecular variables that affect corneal graft rejection pathways. Methods: Illumina Hiseq 2500 deep sequencing was used to screen for differentially expressed genes (DEGs) in matched pairs of isograft corneas and normal corneas, allograft corneas and isograft corneas. Potential target genes among the DEGs were predicted using target prediction software (TargetScan, Miranda, miRDB, and CLIP), and the overlay portion was analyzed using the Gene Ontology (GO) database and the Kyoto Encyclopedia of Genes and Genomes (KEGG). An analysis of the interactions between DEG proteins (PPI analysis) and a MetaCore software analysis. Results: Our results showed that 22 miRNAs were significantly upregulated and 4 were significantly downregulated in the isograft group when compared with the control group (P < 0.01), while 17 miRNAs were significantly upregulated and 3 were significantly downregulated in the allograft group when compared with the isograft group (P < 0.01). Among the miRNAs with altered expression levels, miR-155-5p, miR-142-3p, miR-142-5p, and miR-223-3p displayed simultaneous changes in the above two comparisons. Potential target genes among the DEGs were predicted using target prediction software, and the overlay portion was analyzed using the Gene Ontology (GO) database and the Kyoto Encyclopedia of Genes and Genomes (KEGG). GO and KEGG analyses showed that the DEGs were mainly involved in metabolic pathways, cytokine secretion, and tumor immunity functions. An analysis of the interactions between DEG proteins (PPI analysis) and a MetaCore software analysis of 4 key DEGs revealed that the genes regulated by miR-155-5p played important roles in the miRNA-mRNA regulatory network. Furthermore, the MetaCore analysis identified C/EBP beta, p53, and sp1 as key transcription factors in that network. Conclusions: Our study identified transplanted corneas-specific miRNA in matched pairs of isograft corneas and normal corneas, allograft corneas and isograft corneas. Furthermore, bioinformatics analysis of the key miRNA regulatory network revealed the molecular mechanisms, which suggests miRNAs may as new molecular targets for treating corneal injuries and corneal transplant rejection
Project description:Small non-coding RNAs, in particular microRNAs (miRNAs), regulate fine-tuning of gene expression and can impact a wide range of biological processes. Using deep sequencing analysis, we investigated miRNA expression profiles in central and limbal regions of normal and diabetic human corneas. We identified differentially expressed miRNAs in limbus vs. central cornea in normal and diabetic (DM) corneas including both type I (T1DM/IDDM) and type II (T2DM/NIDDM). Some miRNAs such as miR-10b that was upregulated in limbus vs. central corneas and in diabetic vs. normal limbus also showed significant increase in T1DM vs. T2DM limbus
Project description:Current drugs that directly target pro-angiogenic factors to inhibit or reverse corneal neovascularization, the major sight-threatening pathology caused by angiogenic stimuli, require multiple rounds of administration and have limited efficacies. Here we report the profiling of anti-angiogenic corneal microRNAs (miRNAs), and a framework that employs discovered miRNAs as biotherapies deliverable by recombinant adeno-associated viruses (rAAVs). By querying differentially expressed miRNAs in neovascularized mouse corneas induced by alkali-burn, we have revealed 39 miRNAs that are predicted to target more than 5,500 differentially expressed corneal mRNAs. Among these corneal miRNAs, we selected miR-204 and assessed its efficacy as a therapeutic miRNA in injured corneas. Our results show that delivery of miR-204 by rAAV is efficacious and safe for mitigating corneal NV. Overall, our work demonstrates the discovery of therapeutic miRNAs in corneal disorders and their translation into viable clinical vectors.
Project description:Keratoconus (KTCN) is a complex degenerative eye disorder resulting in loss of visual function. It is known, that its development is affected by both genetic and environmental or behavioral components. In order to verify if DNA methylation may also play a role in KTCN development, reduced representation bisulfite sequencing (RRBS) of human corneas obtained from five KTCN and five non–KTCN individuals was performed.
Project description:This SuperSeries is composed of the following subset Series: GSE15229: Massively Parallel Sequencing Identifies the MicroRNA Transcriptome of Normal and Malignant Human B cells GSE22895: Deep Sequencing of the Small RNA Transcriptome of Normal and Malignant Human B cells Identifies Hundreds of Novel MicroRNAs: microarray analysis Refer to individual Series
Project description:111,556,278 high-quality reads were obtained by a deep-sequencing approach that show an exact match to the genome of Meloidogyne incognita from the library of J2 juveniles of M. incognita (Mi). Based on these Solexa reads, 89 M. incognita microRNA genes were identified, which grouped into 67 non-redundant miRNAs with mature sequences. All of these candidate miRNAs were confirmed by qRT-PCR, and 26 of them could be detected in the library of the galls of cucumber root infected by M. incognita (GC). MiR-100 was found in a cluster with let-7, which is similar with B. malayi, a human parasitic nematode. Based on the results of deep sequencing, the expression of miR-100 was much more abundant than that of let-7, which indicated that they may not be co-expressed. The ortholog of let-7, a key regulator that controls the nematode from L4 to adult in C. elegans, could be frequently sequenced in the GC library, the later stages of development of M. incognita, while it had a relative low expression level in J2, which indicated that let-7 may have a similar role in the development regulation in plant parasitic nematodes. Frequently sequenced microRNAs, including miR-71, miR-100 and miR-124, should play an important role in the growth and proliferation of M. incognita. Identifying microRNAs of M. incognita based on deep-sequencing of the small RNAs of an Mi library, the J2 juveniles, and comparing their expression levels with those in a GC library, the gall of cucumber root infected with M. incognita.
Project description:Characteristic structural details of the cornea are transparency, the absence of blood vessels, and the presence of numerous sensory nerve endings. The corneal epithelium is one of the most densely innervated tissues of the body. The characteristics of the cornea are established during fetal development, and are lost in adult life when the cornea regenerates after injury. The common reaction of the cornea to injury is the formation of opaque scars, the ingrowth of blood vessels, and distinct changes in the innervation pattern. Scar formation of the cornea is critically modulated by the expression of transforming growth factor-beta (TGF-beta). To identify genes that are important for corneal transparency, dense innervation and absence of blood vessels by comparing corneas from wildtype mice with those that are under the influence of high doses of TGF-beta. Transparency, dense innervation, and absence of blood vessels in the cornea all depend on the expression of a critical set of genes that are not expressed when TGF-beta is present. Mice were generated that overexpress TGF-beta under control of a strong lens-specific promoter. These mice developed opaque corneas that are vascularized and lack sensory nerves. In addition, these corneas were densely populated with cells expressing neural cell adhesion protein. RNA was isolated from corneas of transgenic animals and wildtype littermates in order to analyze differentially expressed genes and to identify those that are only expressed in transparent, avascular, and densely innervated wildtype corneas.
Project description:Viral tumor models have significantly contributed to our understanding of oncogenic mechanisms. How transforming delta-retroviruses induce malignancy however remains poorly understood, especially as viral mRNA/protein are tightly silenced in tumors. Here, using deep sequencing of broad windows of small RNA sizes in the Bovine Leukemia Virus ovine model of leukemia/lymphoma, we provide evidence of the production of non-canonical Pol III-transcribed viral microRNAs in leukemic B-cells in the complete absence of Pol II 5' LTR-driven transcriptional activity. Processed from a cluster of five independent self-sufficient transcriptional units located in a proviral region dispensable for in vivo infectivity, BLV microRNAs represent ~ 40 % of all microRNAs in both experimental and natural malignancy. They are conserved across tumors and associate with Argonautes, consistent with a critical function in silencing of important cellular and/or viral targets. BLV microRNAs are strongly expressed at pre-leukemic stages and remain at high levels in malignant cells despite the absence of structural and regulatory gene expression, suggesting a key role in tumor onset and progression. Identification of small RNA populations in BLV-induced leukemia
Project description:Viral tumor models have significantly contributed to our understanding of oncogenic mechanisms. How transforming delta-retroviruses induce malignancy however remains poorly understood, especially as viral mRNA/protein are tightly silenced in tumors. Here, using deep sequencing of broad windows of small RNA sizes in the Bovine Leukemia Virus ovine model of leukemia/lymphoma, we provide evidence of the production of non-canonical Pol III-transcribed viral microRNAs in leukemic B-cells in the complete absence of Pol II 5' LTR-driven transcriptional activity. Processed from a cluster of five independent self-sufficient transcriptional units located in a proviral region dispensable for in vivo infectivity, BLV microRNAs represent ~ 40 % of all microRNAs in both experimental and natural malignancy. They are conserved across tumors and associate with Argonautes, consistent with a critical function in silencing of important cellular and/or viral targets. BLV microRNAs are strongly expressed at pre-leukemic stages and remain at high levels in malignant cells despite the absence of structural and regulatory gene expression, suggesting a key role in tumor onset and progression.