A P53-TLR3 Axis Ameliorates Pulmonary Hypertension by Inducing BMPR2 Via IRF3

Pulmonary arterial hypertension (PAH) features pathogenic and abnormal endothelial cells (ECs), and one potential origin is clonal selection. We studied the role of p53 and toll-like receptor 3 (TLR3) in clonal expansion and pulmonary hypertension (PH) via regulation of bone morphogenetic protein (BMPR2) signaling. ECs of PAH patients had reduced p53 expression. EC-specific p53 knockout exaggerated PH, and clonal expansion reduced p53 and TLR3 expression in rat lung CD117+ ECs. Reduced p53 degradation (Nutlin 3a) abolished clonal EC expansion, induced TLR3 and BMPR2, and ameliorated PH. Polyinosinic/polycytidylic acid [Poly(I:C)] increased BMPR2 signaling in ECs via enhanced binding of interferon regulatory factor-3 (IRF3) to the BMPR2 promoter and reduced PH in p53−/− mice but not in mice with impaired TLR3 downstream signaling. Our data show that a p53/TLR3/IRF3 axis regulates BMPR2 expression and signaling in ECs. This link can be exploited for therapy of PH

A p53-TLR3 axis ameliorates pulmonary hypertension by inducing BMPR2 via IRF3

Pulmonary arterial hypertension (PAH) features pathogenic and abnormal endothelial cells (ECs), and one potential origin is clonal selection. We studied the role of p53 and toll-like receptor 3 (TLR3) in clonal expansion and pulmonary hypertension (PH) via regulation of bone morphogenetic protein (BMPR2) signaling. ECs of PAH patients had reduced p53 expression. EC-specific p53 knockout exaggerated PH, and clonal expansion reduced p53 and TLR3 expression in rat lung CD117+ ECs. Reduced p53 degradation (Nutlin 3a) abolished clonal EC expansion, induced TLR3 and BMPR2, and ameliorated PH. Polyinosinic/polycytidylic acid [Poly(I:C)] increased BMPR2 signaling in ECs via enhanced binding of interferon regulatory factor-3 (IRF3) to the BMPR2 promoter and reduced PH in p53−/− mice but not in mice with impaired TLR3 downstream signaling. Our data show that a p53/TLR3/IRF3 axis regulates BMPR2 expression and signaling in ECs. This link can be exploited for therapy of PH

Plant Tandem CCCH Zinc Finger Proteins Interact with ABA, Drought, and Stress Response Regulators in Processing-Bodies and Stress Granules.

Although multiple lines of evidence have indicated that Arabidopsis thaliana Tandem CCCH Zinc Finger proteins, AtTZF4, 5 and 6 are involved in ABA, GA and phytochrome mediated seed germination responses, the interacting proteins involved in these processes are unknown. Using yeast two-hybrid screens, we have identified 35 putative AtTZF5 interacting protein partners. Among them, Mediator of ABA-Regulated Dormancy 1 (MARD1) is highly expressed in seeds and involved in ABA signal transduction, while Responsive to Dehydration 21A (RD21A) is a well-documented stress responsive protein. Co-immunoprecipitation (Co-IP) and bimolecular fluorescence complementation (BiFC) assays were used to confirm that AtTZF5 can interact with MARD1 and RD21A in plant cells, and the interaction is mediated through TZF motif. In addition, AtTZF4 and 6 could also interact with MARD1 and RD21A in Y-2-H and BiFC assay, respectively. The protein-protein interactions apparently take place in processing bodies (PBs) and stress granules (SGs), because AtTZF5, MARD1 and RD21A could interact and co-localize with each other and they all can co-localize with the same PB and SG markers in plant cells

Introducing collaborative learning into English education in a Sri Lankan university: An exploratory case-study

This thesis is a qualitative exploratory case-study to investigate an enactment of a re-designed English for General Academic Purposes (EGAP) curriculum with collaborative activities in a Sri Lankan university setting. This specifically demonstrates the potential use of a less institutionalised environment for ESL teaching and learning, where ‘collaborative peer social capital’ and ‘peer inculcation’ can be built up. Teachers’ and students’ data were analysed thematically and interpreted with concepts from curriculum studies and Bourdieusian sociology. The intent of the study was to help Sri Lankan ESL learners to overcome negative emotions and social barriers in English language learning

MARD1 and RD21A can co-localize with AtTZF5 and PB (DCP2) and SG (UBP1b) markers in protoplast transient expression analyses.

<p>(A) MARD1 and RD21A can co-localize with AtTZF5 in cytoplasmic foci. (B) MARD1 and RD21A can co-localize with PB marker DCP2. (C) MARD1 and RD21A can co-localize with SG marker UBP1b. Cellular images for GFP and mCherry signals were taken using green and red channel, respectively. Bright field images were also shown for cell integrities. Bar = 10μm.</p

Putative AtTZF5 interacting partners identified by Y-2-H screens.

<p>(A) The representation of 35 proteins identified by Y-2-H screens. (B) Nineteen out of 35 proteins are involved in stress responses. (C) Tissue expression patterns of 35 identified protein-coding genes.</p

AtTZF1 (FL), RR-TZF and TZF of AtTZF5 were expressed in duplicate yeast cell lines.

<p>Shown are results of Western blot analyses. Full-length AtTZF1 as well as RR-TZF and TZF of AtTZF5 were fused with GAL4 DNA binding domain in HA tagged pAS1 vector. HA-ZTL was used as a positive control for the expression in yeast cells.</p

MARD1 and RD21A can interact with AtTZF4 and AtTZF6.

<p>(A, B) MARD1 and RD21A can interact with AtTZF4 and 6 but not AtTZF1 in Y-2-H analysis. AtTZF1, 4, and 6 were fused with GAL4 DNA binding domain (BD), whereas MARD1 and RD21A were fused with GAL4 activation domain (AD). (C) BiFC results indicate that MARD1 and RD21A can interact with AtTZF4 and AtTZF6 in cytolasmic foci in Arabidopsis protoplasts. Images of cells with positive YFP signals were taken by exposing under green channel. Whereas images of cells without YFP signals were taken using all three channels (red, green, and blue) to show cell integrities (red fluorescence from chloroplasts). These experiments were repeated twice. Bar = 10μm.</p