Project description:The genus Lactobacillus contains over 100 different species that were traditionally considered to be uniformly non-motile. However, at least twelve motile species are known to exist in the L. salivarius clade of this genus. Of these, Lactobacillus rumnis is the only motile species that is also autochthonous to the mammalian gastrointestinal tract. The genomes of two L. ruminis strains, ATCC25644 (human isolate, non-motile) and ATCC27782 (bovine isolate, motile) were sequenced and annotated to identify the genes responsible for flagellum biogenesis and chemotaxis in this species. Transcriptome analysis revealed that motility genes were transcribed at a significantly higher level in motile L. ruminis ATCC27782 than in non-motile ATCC25644 during the motile growth phase.
Project description:The genus Lactobacillus contains over 100 different species that were traditionally considered to be uniformly non-motile. However, at least twelve motile species are known to exist in the L. salivarius clade of this genus. Of these, Lactobacillus rumnis is the only motile species that is also autochthonous to the mammalian gastrointestinal tract. The genomes of two L. ruminis strains, ATCC25644 (human isolate, non-motile) and ATCC27782 (bovine isolate, motile) were sequenced and annotated to identify the genes responsible for flagellum biogenesis and chemotaxis in this species. Transcriptome analysis revealed that motility genes were transcribed at a significantly higher level in motile L. ruminis ATCC27782 than in non-motile ATCC25644 during the motile growth phase. In preparation for RNA isolation from L. ruminis ATCC27782 and ATCC25644 cultures in the motile phase, 20 ml aliquots of MRS broth were inoculated (0.25 % inoculum) with a turbid culture of the desired strain. The cultures were incubated anaerobically at 37 °C for 15 hr. In preparation for RNA isolation from L. ruminis ATCC27782 and ATCC25644 cultures in the non-motile growth phase, 20 ml aliquots of MRS broth were inoculated (1 % inoculum) with a turbid culture of the desired strain. The cultures were incubated anaerobically at 37 °C for 16-20 hrs. RNAprotect Bacteria reagent (Qiagen) was used to stabilize gene expression in the target cultures, and total RNA was isolated according to the protocol for enzymatic and mechanical disruption of bacteria as described in the RNAprotect Bacteria Reagent handbook. RNA isolation was completed with the RNeasy Mini kit, and contaminating DNA was removed with the Turbo DNA-free kit (Ambion). An Oligo aCGH/ChIP-on chip hybridization kit (Agilent) was used for hybridization of the labelled cDNA to the microarrays. Probe hybridization took place at 65 °C for 20 hrs with constant rotation (10 rpm). Microarrays were scanned using the Agilent Microarray Scanner System (G2505B) and the scanned files were converted to data files with Feature Extraction software (Agilent). Three microarrays, (three biological replicates) were used to examine gene transcription during the motile growth phase. One microarray was used to examine gene transcription during the non-motile growth phase.
Project description:Impaired drainage of aqueous humor through the trabecular meshwork (TM) culminating in increased intraocular pressure is a major risk factor for glaucoma, a leading cause of blindness worldwide. Regulation of aqueous humor drainage through the TM, however, is poorly understood. The role of RhoA GTPase-mediated contractile activity, cell adhesive interactions, and gene expression in regulation of aqueous humor outflow was investigated using adenoviral vector-driven expression of constitutively active RhoA (RhoAV14). Organ cultured anterior segments from porcine eyes expressing RhoAV14 exhibited significant reduction of aqueous humor outflow. Cultured TM cells expressing RhoAV14 revealed strong contractile cell morphology, increased actin stress fibers and focal adhesions, along with increased levels of phosphorylated myosin II, and collagen IV, fibronectin and laminin. cDNA microarray analysis of RNA extracted from RhoAV14 expressing human TM cells revealed a significant increase in the expression of genes encoding extracellular matrix (ECM) proteins, cytokines, integrins, cytoskeletal proteins and signaling proteins. Conversely, various ECM proteins stimulated robust increases in phosphorylation of myosin II, paxillin and focal adhesion kinase, and activated Rho GTPase and actin stress fiber formation in TM cells, indicating a potential regulatory feedback interaction between ECM-induced mechanical strain and Rho GTPase-induced isometric tension in TM cells. Collectively, these data demonstrate that sustained activation of Rho GTPase signaling in the aqueous humor outflow pathway increases resistance to aqueous humor outflow through the trabecular pathway by influencing the contractile force, cell adhesive interactions, and the expression of ECM proteins and cytokines in TM cells. Keywords: Gene Expression Two condition experiment: Human trabecular mesh work cells infected with Adenivirus expressing GFP Vs Adenovirus expressing GFP and constitutively active RhoAV14
Project description:Purpose: To characterize microRNAs (miRNAs) and their possible roles in high myopia by using next generation sequencing Methods: Aqueous humor samples were obtained from 15 highly myopic eyes and 15 cataract eyes at the onset of surgery. miRNA next generation sequencing and bioinformatics analyses were performed using RNA extracted from aqueous humor samples. Results: A total of 341 miRNAs were detected in the aqueous humor samples of highly myopic eyes; 201 miRNAs were detected in the aqueous humor samples of cataractous control eyes. A total of 249 mature miRNAs and 17 novel miRNAs were differentially expressed during myopia. Possible pathways regulated by these aberrantly expressed miRNAs included the TNF, MAPK, PI3K-Akt, and HIF-1 signaling pathways. Conclusions: The current study provided an overall view of miRNA profiling in the aqueous humor of highly myopic eyes. These profiles may be associated with myopia pathogenesis, and are potential biomarkers.