EUV Emission and Scattered Light Diagnostics of Equatorial Coronal Holes as Seen by Hinode/EIS

Spectroscopic diagnostics of solar coronal plasmas critically depends on the uncertainty in the measured line intensities. One of the main sources of uncertainty is instrumental scattered light, which is potentially most important in low-brightness areas. In the solar corona, such areas include polar and equatorial coronal holes, which are the source regions of the solar wind; instrument-scattered light must thus pose a significant obstacle to studies of the source regions of the solar wind. In this paper we investigate the importance of instrument-scattered light on observations of equatorial coronal holes made by the Hinode/EIS spectrometer in two different phases of the solar cycle. We find that the instrument-scattered light is significant at all temperatures, and in both regions it amounts to approximately 10% of the average intensity of the neighboring quiet Sun regions. Such contribution dominates the measured intensity for spectral lines formed at temperatures larger than Log T = 6.15 K, and has deep implications for spectroscopic diagnostics of equatorial coronal hole plasmas and studies of the source regions of a large portion of the solar wind which reaches Earth. Our results suggest that the high temperature tail of in the coronal hole plasma distribution with temperature, however small, is an artifact due to the presence of scattered light.Comment: 11 pages, 6 figure

Image_4_A Potential Compensatory Role of Panx3 in the VNO of a Panx1 Knock Out Mouse Model.JPEG

<p>Pannexins (Panx) are integral membrane proteins, with Panx1 being the best-characterized member of the protein family. Panx1 is implicated in sensory processing, and knockout (KO) animal models have become the primary tool to investigate the role(s) of Panx1 in sensory systems. Extending previous work from our group on primary olfaction, the expression patterns of Panxs in the vomeronasal organ (VNO), an auxiliary olfactory sense organ with a role in reproduction and social behavior, were compared. Using qRT-PCR and Immunohistochemistry (IHC), we confirmed the loss of Panx1, found similar Panx2 expression levels in both models, and a significant upregulation of Panx3 in mice with a global ablation of Panx1. Specifically, Panx3 showed upregulated expression in nerve fibers of the non-sensory epithelial layer in juvenile and adult KO mice and in the sensory layer of adults, which overlaps with Panx1 expression areas in WT populations. Since both social behavior and evoked ATP release in the VNO was not compromised in KO animals, we hypothesized that Panx3 could compensate for the loss of Panx1. This led us to compare Panx1 and Panx3 channels in vitro, demonstrating similar dye uptake and ATP release properties. Outcomes of this study strongly suggest that Panx3 may functionally compensate for the loss of Panx1 in the VNO of the olfactory system, ensuring sustained chemosensory processing. This finding extends previous reports on the upregulation of Panx3 in arterial walls and the skin of Panx1 KO mice, suggesting that roles of Panx1 warrant uncharacterized safeguarding mechanisms involving Panx3.</p

Image_3_A Potential Compensatory Role of Panx3 in the VNO of a Panx1 Knock Out Mouse Model.JPEG

<p>Pannexins (Panx) are integral membrane proteins, with Panx1 being the best-characterized member of the protein family. Panx1 is implicated in sensory processing, and knockout (KO) animal models have become the primary tool to investigate the role(s) of Panx1 in sensory systems. Extending previous work from our group on primary olfaction, the expression patterns of Panxs in the vomeronasal organ (VNO), an auxiliary olfactory sense organ with a role in reproduction and social behavior, were compared. Using qRT-PCR and Immunohistochemistry (IHC), we confirmed the loss of Panx1, found similar Panx2 expression levels in both models, and a significant upregulation of Panx3 in mice with a global ablation of Panx1. Specifically, Panx3 showed upregulated expression in nerve fibers of the non-sensory epithelial layer in juvenile and adult KO mice and in the sensory layer of adults, which overlaps with Panx1 expression areas in WT populations. Since both social behavior and evoked ATP release in the VNO was not compromised in KO animals, we hypothesized that Panx3 could compensate for the loss of Panx1. This led us to compare Panx1 and Panx3 channels in vitro, demonstrating similar dye uptake and ATP release properties. Outcomes of this study strongly suggest that Panx3 may functionally compensate for the loss of Panx1 in the VNO of the olfactory system, ensuring sustained chemosensory processing. This finding extends previous reports on the upregulation of Panx3 in arterial walls and the skin of Panx1 KO mice, suggesting that roles of Panx1 warrant uncharacterized safeguarding mechanisms involving Panx3.</p

IRES-mediated translation of the carboxy-terminal domain of the horizontal cell specific connexin Cx55.5 in vivo and in vitro-6

Re (HP), the chimeric human globin intron (137 nt), and the primers used for RT-PCR analysis indicated as arrows (see Additional file ). B) RT-PCR from N2A cells transiently transfected with the control vector pRF-Di cis and the pRF-IR2 construct. A 1 kbp DNA ladder is shown on the left side of the gel. NTC, denotes no template control, PCR products generated from plasmid DNA are denoted as plasmid. RT-PCR products are indicated as cDNA. The 18s rRNA control PCR served as internal standard as described previously (49)<p><b>Copyright information:</b></p><p>Taken from "IRES-mediated translation of the carboxy-terminal domain of the horizontal cell specific connexin Cx55.5 in vivo and in vitro"</p><p>http://www.biomedcentral.com/1471-2199/9/52</p><p>BMC Molecular Biology 2008;9():52-52.</p><p>Published online 27 May 2008</p><p>PMCID:PMC2435236.</p><p></p

Image_5_A Potential Compensatory Role of Panx3 in the VNO of a Panx1 Knock Out Mouse Model.jpg

<p>Pannexins (Panx) are integral membrane proteins, with Panx1 being the best-characterized member of the protein family. Panx1 is implicated in sensory processing, and knockout (KO) animal models have become the primary tool to investigate the role(s) of Panx1 in sensory systems. Extending previous work from our group on primary olfaction, the expression patterns of Panxs in the vomeronasal organ (VNO), an auxiliary olfactory sense organ with a role in reproduction and social behavior, were compared. Using qRT-PCR and Immunohistochemistry (IHC), we confirmed the loss of Panx1, found similar Panx2 expression levels in both models, and a significant upregulation of Panx3 in mice with a global ablation of Panx1. Specifically, Panx3 showed upregulated expression in nerve fibers of the non-sensory epithelial layer in juvenile and adult KO mice and in the sensory layer of adults, which overlaps with Panx1 expression areas in WT populations. Since both social behavior and evoked ATP release in the VNO was not compromised in KO animals, we hypothesized that Panx3 could compensate for the loss of Panx1. This led us to compare Panx1 and Panx3 channels in vitro, demonstrating similar dye uptake and ATP release properties. Outcomes of this study strongly suggest that Panx3 may functionally compensate for the loss of Panx1 in the VNO of the olfactory system, ensuring sustained chemosensory processing. This finding extends previous reports on the upregulation of Panx3 in arterial walls and the skin of Panx1 KO mice, suggesting that roles of Panx1 warrant uncharacterized safeguarding mechanisms involving Panx3.</p

IRES-mediated translation of the carboxy-terminal domain of the horizontal cell specific connexin Cx55.5 in vivo and in vitro-7

Ts were transiently expressed in NIH3T3 cells. Confocal images were collected using the LSM510 Meta system and software. Pictures shown represent single optical planes which are presented in pseudocolours for better representation of the staining intensity. Red label indicates maximal concentration. A, B) Wild-type Cx55.5 construct (WT) co-expressing the full length Cx55.5-FLAG and p11-CT-FLAG fusion proteins. (magnification in A: 40×, Scale bar = 30 μm; in B: 63× magnification, Scale bar = 15 μm). Highest concentrations occur in perinuclear regions and the nucleus. B) Higher magnification of the WT construct with a ROI (1) showing punctuate membrane label. C) FLAG-tagged p11-CT with maximal concentration in the nuclei. The arrowheads in the inset indicates the characteristic nuclear localization of p11-CT. (magnification: 40×; Scale bar 30 μm). D) FLAG-tagged FL protein encoding for the full length Cx55.5 protein only (magnification 63×, Scale bar: 15 μm). Besides lack of nuclear staining plaque-like protein assemblies occur at sites of cell contacts (indicated by arrowheads in inset 2 and 3). Such membrane bound fluorescence was not observed with the p11-CT construct. (E) Western blot analysis of cytosolic and nuclear fractions of Cx55.5-FLAG, FL-FLAG and p11-CT-FLAG transfected N2A cells. 20 μg of total nuclear and 10 μg of cytosolic protein was separated by SDS-PAGE on a 12% gel. Immunoblot detection was done using anti-Cx55.5 as primary antibody (1 μg/ml). The upper lanes represent the full length Cx55.5 protein products expressed by the Cx55.5 wildtype protein and the FL mutant. The middle lane refers to the p11-CT protein expressed by the Cx55.5 wildtype and p11-CT proteins, but not by the FL mutation. The lower blot depicts the β-actin control. Note that the β-actin signal in the nuclear fraction is significantly reduced despite the fact that more protein was loaded on the gel. This indicates a minimal contamination with cytoplasmic remnants.<p><b>Copyright information:</b></p><p>Taken from "IRES-mediated translation of the carboxy-terminal domain of the horizontal cell specific connexin Cx55.5 in vivo and in vitro"</p><p>http://www.biomedcentral.com/1471-2199/9/52</p><p>BMC Molecular Biology 2008;9():52-52.</p><p>Published online 27 May 2008</p><p>PMCID:PMC2435236.</p><p></p

Image_2_A Potential Compensatory Role of Panx3 in the VNO of a Panx1 Knock Out Mouse Model.JPEG

<p>Pannexins (Panx) are integral membrane proteins, with Panx1 being the best-characterized member of the protein family. Panx1 is implicated in sensory processing, and knockout (KO) animal models have become the primary tool to investigate the role(s) of Panx1 in sensory systems. Extending previous work from our group on primary olfaction, the expression patterns of Panxs in the vomeronasal organ (VNO), an auxiliary olfactory sense organ with a role in reproduction and social behavior, were compared. Using qRT-PCR and Immunohistochemistry (IHC), we confirmed the loss of Panx1, found similar Panx2 expression levels in both models, and a significant upregulation of Panx3 in mice with a global ablation of Panx1. Specifically, Panx3 showed upregulated expression in nerve fibers of the non-sensory epithelial layer in juvenile and adult KO mice and in the sensory layer of adults, which overlaps with Panx1 expression areas in WT populations. Since both social behavior and evoked ATP release in the VNO was not compromised in KO animals, we hypothesized that Panx3 could compensate for the loss of Panx1. This led us to compare Panx1 and Panx3 channels in vitro, demonstrating similar dye uptake and ATP release properties. Outcomes of this study strongly suggest that Panx3 may functionally compensate for the loss of Panx1 in the VNO of the olfactory system, ensuring sustained chemosensory processing. This finding extends previous reports on the upregulation of Panx3 in arterial walls and the skin of Panx1 KO mice, suggesting that roles of Panx1 warrant uncharacterized safeguarding mechanisms involving Panx3.</p

IRES-mediated translation of the carboxy-terminal domain of the horizontal cell specific connexin Cx55.5 in vivo and in vitro-4

File for further explanation). B) IRES activity and cryptic activity of the above constructs in N2A, HeLa and NIH3T3 cells. The IRES activity is represented as the ratio of to luciferase (FLuc/RLuc) with the activity of the control vector, pRF-Di cis, set at "1". Each construct was tested three times and each experiment was done in triplicate. Data are expressed as mean ± SEM<p><b>Copyright information:</b></p><p>Taken from "IRES-mediated translation of the carboxy-terminal domain of the horizontal cell specific connexin Cx55.5 in vivo and in vitro"</p><p>http://www.biomedcentral.com/1471-2199/9/52</p><p>BMC Molecular Biology 2008;9():52-52.</p><p>Published online 27 May 2008</p><p>PMCID:PMC2435236.</p><p></p

Image_1_A Potential Compensatory Role of Panx3 in the VNO of a Panx1 Knock Out Mouse Model.JPEG

<p>Pannexins (Panx) are integral membrane proteins, with Panx1 being the best-characterized member of the protein family. Panx1 is implicated in sensory processing, and knockout (KO) animal models have become the primary tool to investigate the role(s) of Panx1 in sensory systems. Extending previous work from our group on primary olfaction, the expression patterns of Panxs in the vomeronasal organ (VNO), an auxiliary olfactory sense organ with a role in reproduction and social behavior, were compared. Using qRT-PCR and Immunohistochemistry (IHC), we confirmed the loss of Panx1, found similar Panx2 expression levels in both models, and a significant upregulation of Panx3 in mice with a global ablation of Panx1. Specifically, Panx3 showed upregulated expression in nerve fibers of the non-sensory epithelial layer in juvenile and adult KO mice and in the sensory layer of adults, which overlaps with Panx1 expression areas in WT populations. Since both social behavior and evoked ATP release in the VNO was not compromised in KO animals, we hypothesized that Panx3 could compensate for the loss of Panx1. This led us to compare Panx1 and Panx3 channels in vitro, demonstrating similar dye uptake and ATP release properties. Outcomes of this study strongly suggest that Panx3 may functionally compensate for the loss of Panx1 in the VNO of the olfactory system, ensuring sustained chemosensory processing. This finding extends previous reports on the upregulation of Panx3 in arterial walls and the skin of Panx1 KO mice, suggesting that roles of Panx1 warrant uncharacterized safeguarding mechanisms involving Panx3.</p

IRES-mediated translation of the carboxy-terminal domain of the horizontal cell specific connexin Cx55.5 in vivo and in vitro-3

M cistron, with two stable stem-loops or hairpins (HP), one at the 5' end and another at 3' end of luciferase gene. pRF-IR1 construct carrying the coding region (from nt631 to nt1200) of the CT in the intercistronic region, and pRF-IR2 construct with the coding region (from nt631 to nt990) of the CT in the intercistronic region. B) IRES activity of the above three constructs in N2A, HeLa and NIH3T3 cells. The IRES activity is represented as ratio of to luciferase activity (FLuc/RLuc) with the activity of the control vector, pRF-Di cis set is at 1. Each construct was tested five times and each experiment was done in triplicate. Data are expressed as mean ± SEM.<p><b>Copyright information:</b></p><p>Taken from "IRES-mediated translation of the carboxy-terminal domain of the horizontal cell specific connexin Cx55.5 in vivo and in vitro"</p><p>http://www.biomedcentral.com/1471-2199/9/52</p><p>BMC Molecular Biology 2008;9():52-52.</p><p>Published online 27 May 2008</p><p>PMCID:PMC2435236.</p><p></p