كان مدعوما من قبل SL الزمالة من DFG (مدرسة عليا للبحوث 845). وأيد هذا العمل من المنح المقدمة من (530/C1 SFB ول967) DFG وHOMFOR.

<ol>
	<li>Clapham, D. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Calcium+signalling.">Calcium signalling.</a> Cell. 131, 1047-1058 (2007).</li><li>Lomax, R. B., Camello, C., Van Coppenolle, F., Petersen, O. H., Tepikin, A. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Basal+and+physiological+Ca2++leak+from+the+endoplasmic+reticulum+of+pancreatic+acinar+cells.">Basal and physiological Ca2+ leak from the endoplasmic reticulum of pancreatic acinar cells.</a> J. Biol. Chem. 277, 26479-26485 (2002).</li><li>Van Coppenolle, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ribosome-translocon+complex+mediates+calcium+leakage+from+endoplasmic+reticulum+stores.">Ribosome-translocon complex mediates calcium leakage from endoplasmic reticulum stores.</a> J. Cell Sci. 117, 4135-4142 (2004).</li><li>Flourakis, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Passive+calcium+leak+via+translocon+is+a+first+step+for+iPLA2-pathway+regulated+store+operated+channel+activation.">Passive calcium leak via translocon is a first step for iPLA2-pathway regulated store operated channel activation.</a> FASEB J. 20, 1215-1217 (2006).</li><li>Giunti, R., Gamberucci, A., Fulceri, R., Banhegyi, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Both+translocon+and+a+cation+channel+are+involved+in+the+passive+Ca2++leak+from+the+endoplasmic+reticulum:+a+mechanistic+study+on+rat+liver+microsomes.">Both translocon and a cation channel are involved in the passive Ca2+ leak from the endoplasmic reticulum: a mechanistic study on rat liver microsomes.</a> Arch. Biochem. Biophys. 462, 115-121 (2007).</li><li>Ong, H. L., Liu, X., Sharma, A., Hegde, R. S., Ambudkar, I. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intracellular+Ca2++release+via+the+ER+translocon+activates+store+operated+calcium+entry.">Intracellular Ca2+ release via the ER translocon activates store operated calcium entry.</a> Pflugers Arch. Eur. J. Physiol. 453, 797-808 (2007).</li><li>Amer, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Translocon+closure+to+Ca2++leak+in+proliferating+vascular+smooth+muscle+cells.">Translocon closure to Ca2+ leak in proliferating vascular smooth muscle cells.</a> Am. J. Physiol. Heart Circ. Physiol. 296, 910-916 (2009).</li><li>Tu, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Presenilins+form+ER+Ca2++leak+channels,+a+function+disrupted+by+familial+Alzheimer's+disease-linked+mutations.">Presenilins form ER Ca2+ leak channels, a function disrupted by familial Alzheimer's disease-linked mutations.</a> Cell. 126, 981-993 (2006).</li><li>Hamman, B. D., Hendershot, L. M., Johnson, A. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=BiP+maintains+the+permeability+barrier+of+the+ER+membrane+by+sealing+the+lumenal+end+of+the+translocon+pore+before+and+early+in+translocation.">BiP maintains the permeability barrier of the ER membrane by sealing the lumenal end of the translocon pore before and early in translocation.</a> Cell. 92, 747-758 (1998).</li><li>Alder, N. N., Shen, Y., Brodsky, J. L., Hendershot, L. M., Johnson, A. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+molecular+mechanism+underlying+BiP-mediated+gating+of+the+Sec61+translocon+of+the+endoplasmic+reticulum.">The molecular mechanism underlying BiP-mediated gating of the Sec61 translocon of the endoplasmic reticulum.</a> J. Cell Biol. 168, 389-399 (2005).</li><li>Aneiros, E., Philipp, S. E., Lis, A., Freichel, M., Cavalie, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modulation+of+Ca2++signalling+by+Na+/Ca2++exchangers+in+mast+cells.">Modulation of Ca2+ signalling by Na+/Ca2+ exchangers in mast cells.</a> J. Immunol. 174, 119-130 (2005).</li><li>Gross, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TRPC5+is+a+Ca2+-activated+channel+functionally+coupled+to+Ca2+-selective+ion+channels.">TRPC5 is a Ca2+-activated channel functionally coupled to Ca2+-selective ion channels.</a> J. Biol. Chem. 284, 34423-34432 (2009).</li><li>Erdmann, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interaction+of+calmodulin+with+Sec61a+limit+Ca2++leakage+from+the+endoplasmic+reticulum.">Interaction of calmodulin with Sec61a limit Ca2+ leakage from the endoplasmic reticulum.</a> EMBO J. 30, 17-31 (2011).</li></ol>

الإعلان عن أي تضارب في المصالح.

في خلايا الثدييات ، وشبكية هيولي باطني (ER) يلعب دورا رئيسيا في نشوء حيوي البروتين وكذلك في إشارة الكالسيوم. هنا ، وقد وصفت لنا نظام التجريبية التي تسمح لنا للتصدي بشكل مباشر على دور قناة واحدة الكالسيوم + 2 تسرب محتمل لتوصيف وآلياتها التنظيمية المفترضة 13. هذا النظام التجريبي يعطينا فرصا فريدة لط) تقييم مساهمة مختلف البروتينات إلى غشاء ER السلبي كا 2 + هروب من لائحة في مختلف أنواع الخلايا ، والثاني) توصيف البروتينات والآليات التي تحد من هذا كا 2 + السلبي هروب رأس المال ، و ج) دراسة آثار الطفرات المرض المرتبط في العناصر ذات الصلة. نلاحظ أنه ينبغي تحليل الخلايا الوحيد القابل للتطبيق والجدوى الشاملة التي يجب أن تكون فوق 80 ٪. لذلك ، يتم تقييمها بشكل روتيني بقاء الخلية توظيف النووية معرف بقاء الخلية الزرقاء / الخضراء كاشف وفقا لبروتوكول الشركة المصنعة. وعلاوة على ذلك ، والتحليل الإحصائي للتغيرات في عصاري خلوي كا 2 + تركيز إلزامي. لذلك ، يجب أن تكون التجارب التي أجريت على أربع دفعات مختلفة من الخلايا وcoverslips مع اثنين لا يقل عن 20 خلايا لديك ليتم تحليلها من أجل كل حالة في تجربة واحدة. نلاحظ أن التجارب المختلفة والتي يتعين الاضطلاع بها في نفس الوقت بعد البذر على زلات الغطاء.

<table border="1" style=";text-align:right;direction:rtl"><tbody><tr><th> اسم كاشف </th><th> شركة </th><th> فهرس العدد </th></tr><tr><td> DMEM + GlutaMAX </td><td> Invitrogen </td><td> 31966 </td></tr><tr><td> OptiMEM + GlutaMAX </td><td> Invitrogen </td><td> 51985 </td></tr><tr><td> FBS </td><td> Biochrom </td><td> S0115 </td></tr><tr><td> البنسلين / الستربتوميسين </td><td> PAA </td><td> P11 - 010 </td></tr><tr><td> HiPerFect </td><td> Qiagen </td><td> 301707 </td></tr><tr><td> Fugene HD </td><td> روش تشخيص </td><td> 04709713 </td></tr><tr><td> معرف النووية الأزرق / الأخضر كاشف بقاء الخلية </td><td> انزو العلوم الحياتية </td><td> ENZ - 53004 </td></tr><tr><td> FURA ، 02:00 </td><td> Invitrogen </td><td> F - 1221 </td></tr><tr><td> بوروميسين </td><td> سيغما </td><td> ف 7255 </td></tr><tr><td> Thapsigargin </td><td> Invitrogen </td><td> T - 7459 </td></tr><tr><td> Ophiobolin A </td><td> انزو العلوم الحياتية </td><td> ALX ، 270-109 </td></tr><tr><td> تريفلوبيرازين </td><td> سيغما </td><td> تي 6062 </td></tr><tr><td> كونتيسة ® الآلي خلية مكافحة </td><td> Invitrogen </td><td></td></tr><tr><td> الاعصار الثلاثي نظام التصوير </td><td> جنرال إلكتريك للرعاية الصحية </td><td></td></tr><tr><td> TE2000 - S المجهر مع DS - 5Mc الكاميرا </td><td> نيكون </td><td></td></tr><tr><td> iMIC المجهر الخامس مع الملون </td><td> حتى الضوئيات </td><td></td></tr></tbody></table>

live cell calcium imaging combined with sirna mediated gene silencing identifies ca2+ leak channels in the er membrane and their regulatory mechanisms

في خلايا الثدييات ، وشبكية هيولي باطني (ER) يلعب دورا رئيسيا في نشوء حيوي البروتين والكالسيوم وكذلك في إشارة 1. وheterotrimeric Sec61 معقدة في الغشاء ER يوفر مسارا مائي لالبروتينية حديثا توليفها في التجويف من لائحة. العمل الأخير من مختلف المختبرات واقترح أن هذا المجمع قد تشكل أيضا heterotrimeric كا عابر 2 + قنوات تسرب 2-8. كانت الملاحظة الرئيسية لهذه الفكرة التي تطلق من البروتينية الوليدة من الريبوسوم والمعقدة التي Sec61 بوروميسين يؤدي إلى الإفراج عابر كا 2 + من لائحة. علاوة على ذلك ، فقد لوحظ في المختبر أن يشارك البروتين اللمعية ER بيب في منع نفاذية أيون على مستوى 9،10 Sec61 المجمع. لقد أنشأنا نظاما التجريبية التي تسمح لنا لمعالجة مباشرة لدور مجمع Sec61 المحتملة كما كا قناة + 2 وتسرب لتوصيف آلياتها التنظيمية المفترضة 11-13. هذا النظام يجمع بين إسكات الجينات بوساطة سيرنا والخلية الحية كا 2 + التصوير 13. تعامل مع الخلايا siRNAs الموجهة ضد الترميز والمنطقة غير المترجمة (UTR) على التوالي ، من الجينات أو SEC61A1 سيرنا السيطرة السلبية. في تحليل تكامل ، هي الخلايا المشترك مع ناقلات transfected IRES - GFP التي تسمح للمقاومة سيرنا التعبير عن الجينات SEC61A1 wildtype. ثم يتم تحميلها على الخلايا التي تحتوي على الكالسيوم ratiometric - 2 + مؤشر FURA - 2 لرصد التغيرات في وقت واحد في عصاري خلوي كا 2 + التركيز في عدد من الخلايا عبر مجهر مضان. القياس المستمر للعصاري خلوي كا 2 + يسمح أيضا لتقييم تأثير عوامل مختلفة ، مثل بوروميسين ، مثبطات جزيء صغير ، وعلى thapsigargin كا 2 + التسرب. هذا النظام التجريبي يعطينا فرصا فريدة لط) تقييم مساهمة مختلف البروتينات إلى غشاء ER السلبي كا 2 + هروب من لائحة في مختلف أنواع الخلايا ، والثاني) توصيف البروتينات والآليات التي تحد من هذا كا 2 + السلبي هروب رأس المال ، و ج) دراسة آثار الطفرات المرض المرتبط في العناصر ذات الصلة.

Watch this Scientific Journal Video about Live Cell Calcium Imaging Combined with siRNA Mediated Gene Silencing Identifies Ca2+ Leak Channels in the ER Membrane and their Regulatory Mechanisms at JoVE

Live Cell Calcium Imaging Combined with siRNA Mediated Gene Silencing Identifies Ca2+ Leak Channels in the ER Membrane and their Regulatory Mechanisms

في شبكية هيولي باطني يلعب دورا رئيسيا في نشوء حيوي في البروتين والكالسيوم. لقد أنشأنا نظاما التجريبية التي تسمح لنا لمعالجة دور قنوات + CA2 وتسرب لتوصيف آلياتها التنظيمية المفترضة. هذا النظام ينطوي على إسكات الجينات بوساطة سيرنا والخلية الحية CA2 + التصوير.

يعيش التصوير الكالسيوم الخلية المشتركة مع وساطة سيرنا إسكات الجينات يحدد كا 2 + قنوات تسرب في غشاء ER وآلياتها التنظيمية

In mammalian cells, the endoplasmic reticulum (ER) plays a key role in protein biogenesis as well as in calcium signalling1. The heterotrimeric Sec61 ...

live-cell-calcium-imaging-combined-with-sirna-mediated-gene-silencing

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Biology

Live Cell Calcium Imaging Combined with siRNA Mediated Gene Silencing Identifies Ca2+ Leak Channels in the ER Membrane and their Regulatory Mechanisms

18.0K Views.  Saarland University. في شبكية هيولي باطني يلعب دورا رئيسيا في نشوء حيوي في البروتين والكالسيوم. لقد أنشأنا نظاما التجريبية التي تسمح لنا لمعالجة دور قنوات + CA2 وتسرب لتوصيف آلياتها التنظيمية المفترضة. هذا النظام ينطوي على إسكات الجينات بوساطة سيرنا والخلية الحية CA2 + التصوير.

Video: Live Cell Calcium Imaging Combined with siRNA Mediated Gene Silencing Identifies Ca2+ Leak Channels in the ER Membrane and their Regulatory Mechanisms

Studying Membrane Biogenesis with a Luciferase-Based Reporter Gene Assay

To study the coordination of different lipid synthesis pathways during membrane biogenesis it is useful to work with an experimental system where membrane biogenesis occurs rapidly and in an inducible manner. We have found that phagocytosis of latex beads is practical for these purposes as cells rapidly synthesize membrane lipids to replenish membrane pools lost as  wrapping material  during particle engulfment. Here, we describe procedures for studying changes in phagocytosis-induced gene expression with a luciferase-based reporter gene approach using the Dual-Glo  Luciferase Assay System from Promega.

Here, we describe procedures for studying changes in phagocytosis-induced gene expression with a luciferase-based reporter gene approach using the Dual-GloTM Luciferase Assay System from Promega.

دراسة النشوء الأحيائي الأغشية مع الفحص الجيني مراسل Luciferase المستندة

To study the coordination of different lipid synthesis pathways during membrane biogenesis it is useful to work with an experimental system where membrane ...

Agrobacterium-Mediated Virus-Induced Gene Silencing Assay In Cotton

Cotton (Gossypium hirsutum) is one of the most important crops worldwide. Considerable efforts have been made on molecular breeding of new varieties. The large-scale gene functional analysis in cotton has been lagged behind most of the modern plant species, likely due to its large size of genome, gene duplication and polyploidy, long growth cycle and recalcitrance to genetic transformation1. To facilitate high throughput functional genetic/genomic study in cotton, we attempt to develop rapid and efficient transient assays to assess cotton gene functions.
Virus-Induced Gene Silencing (VIGS) is a powerful technique that was developed based on the host Post-Transcriptional Gene Silencing (PTGS) to repress viral proliferation2,3. Agrobacterium-mediated VIGS has been successfully applied in a wide range of dicots species such as Solanaceae, Arabidopsis and legume species, and monocots species including barley, wheat and maize, for various functional genomic studies3,4. As this rapid and efficient approach avoids plant transformation and overcomes functional redundancy, it is particularly attractive and suitable for functional genomic study in crop species like cotton not amenable for transformation.
In this study, we report the detailed protocol of Agrobacterium-mediated VIGS system in cotton. Among the several viral VIGS vectors, the tobacco rattle virus (TRV) invades a wide range of hosts and is able to spread vigorously throughout the entire plant yet produce mild symptoms on the hosts5. To monitor the silencing efficiency, GrCLA1, a homolog gene of Arabidopsis Cloroplastos alterados 1 gene (AtCLA1) in cotton, has been cloned and inserted into the VIGS binary vector pYL156. CLA1 gene is involved in chloroplast development6, and previous studies have shown that loss-of-function of AtCLA1 resulted in an albino phenotype on true leaves7, providing an excellent visual marker for silencing efficiency. At approximately two weeks post Agrobacterium infiltration, the albino phenotype started to appear on the true leaves, with 100% silencing efficiency in all replicated experiments. The silencing of endogenous gene expression was also confirmed by RT-PCR analysis. Significantly, silencing could potently occur in all the cultivars we tested, including various commercially grown varieties in Texas. This rapid and efficient Agrobacterium-mediated VIGS assay provides a very powerful tool for rapid large-scale analysis of gene functions at genome-wide level in cotton.

We present the detailed protocol for Agrobacterium-mediated virus-induced gene silencing (VIGS) assay in cotton. The tobacco rattle virus (TRV)-derived VIGS vectors were deployed to induce RNA silencing of cotton GrCLA1, Cloroplastos alterados 1 gene. The albino phenotype caused by silencing GrCLA1 was observed at the seedling stage within 2 weeks after inoculation.

الأجرعية بوساطة الفيروسات إسكات الجينات المستحثة الفحص في القطن

Cotton (Gossypium hirsutum) is one of the most important crops worldwide. Considerable efforts have been made on molecular breeding of new varieties.  The ...

Live Imaging of Apoptotic Cell Clearance during Drosophila Embryogenesis

The proper elimination of unwanted or aberrant cells through apoptosis and subsequent phagocytosis (apoptotic cell clearance) is crucial for normal development in all metazoan organisms. Apoptotic cell clearance is a highly dynamic process intimately associated with cell death; unengulfed apoptotic cells are barely seen in vivo under normal conditions. In order to understand the different steps of apoptotic cell clearance and to compare 'professional' phagocytes - macrophages and dendritic cells to 'non-professional' - tissue-resident neighboring cells, in vivo live imaging of the process is extremely valuable. Here we describe a protocol for studying apoptotic cell clearance in live Drosophila embryos. To follow the dynamics of different steps in phagocytosis we use specific markers for apoptotic cells and phagocytes. In addition, we can monitor two phagocyte systems in parallel: 'professional' macrophages and 'semi-professional' glia in the developing central nervous system (CNS). The method described here employs the Drosophila embryo as an excellent model for real time studies of apoptotic cell clearance.

Live Imaging of Apoptotic Cell Clearance during Drosophila Embryogenesis

Here we describe an effective method for studying dynamics of apoptotic cell clearance in vivo. This method employs live Drosophila embryos as a powerful model for monitoring phagocytosis of apoptotic cells using specific labeling of apoptotic cells and phagocytes.

يعيش التصوير من تخليص الخلية أفكارك أثناء<em&gt; ذبابة الفاكهة</em&gt; مرحلة التطور الجنيني

The  proper elimination of unwanted or aberrant cells through apoptosis and  subsequent phagocytosis (apoptotic cell clearance) is crucial for normal  ...

Direct Imaging of ER Calcium with Targeted-Esterase Induced Dye Loading (TED)

Visualization of calcium dynamics is important to understand the role of calcium in cell physiology. To examine calcium dynamics, synthetic fluorescent Ca2+ indictors have become popular. Here we demonstrate TED (= targeted-esterase induced dye loading), a method to improve the release of Ca2+ indicator dyes in the ER lumen of different cell types. To date, TED was used in cell lines, glial cells, and neurons in vitro. TED bases on efficient, recombinant targeting of a high carboxylesterase activity to the ER lumen using vector-constructs that express Carboxylesterases (CES). The latest TED vectors contain a core element of CES2 fused to a red fluorescent protein, thus enabling simultaneous two-color imaging. The dynamics of free calcium in the ER are imaged in one color, while the corresponding ER structure appears in red. At the beginning of the procedure, cells are transduced with a lentivirus. Subsequently, the infected cells are seeded on coverslips to finally enable live cell imaging. Then, living cells are incubated with the acetoxymethyl ester (AM-ester) form of low-affinity Ca2+ indicators, for instance Fluo5N-AM, Mag-Fluo4-AM, or Mag-Fura2-AM. The esterase activity in the ER cleaves off hydrophobic side chains from the AM form of the Ca2+ indicator and a hydrophilic fluorescent dye/Ca2+ complex is formed and trapped in the ER lumen. After dye loading, the cells are analyzed at an inverted confocal laser scanning microscope. Cells are continuously perfused with Ringer-like solutions and the ER calcium dynamics are directly visualized by time-lapse imaging. Calcium release from the ER is identified by a decrease in fluorescence intensity in regions of interest, whereas the refilling of the ER calcium store produces an increase in fluorescence intensity. Finally, the change in fluorescent intensity over time is determined by calculation of &Delta;F/F0.

Direct Imaging of ER Calcium with Targeted-Esterase Induced Dye Loading TED

Targeted-esterase induced dye loading (TED) supports the analysis of intracellular calcium store dynamics by fluorescence imaging. The method bases on targeting of a recombinant Carboxylesterase to the endoplasmic reticulum (ER), where it improves the local unmasking of synthetic low-affinity Ca2+ indicator dyes in the ER lumen.

التصوير المباشر من الكالسيوم مع ER-المستهدفة استريز المستحثة صبغ تحميل (TED)

Visualization of calcium dynamics is important to understand the role of calcium in cell physiology. To examine calcium dynamics, synthetic fluorescent ...

Live Imaging Assay for Assessing the Roles of Ca2+ and Sphingomyelinase in the Repair of Pore-forming Toxin Wounds

Plasma membrane injury is a frequent event, and wounds have to be rapidly repaired to ensure cellular survival. Influx of Ca2+ is a key signaling event that triggers the repair of mechanical wounds on the plasma membrane within ~30 sec. Recent studies revealed that mammalian cells also reseal their plasma membrane after permeabilization with pore forming toxins in a Ca2+-dependent process that involves exocytosis of the lysosomal enzyme acid sphingomyelinase followed by pore endocytosis. Here, we describe the methodology used to demonstrate that the resealing of cells permeabilized by the toxin streptolysin O is also rapid and dependent on Ca2+ influx. The assay design allows synchronization of the injury event and a precise kinetic measurement of the ability of cells to restore plasma membrane integrity by imaging and quantifying the extent by which the liphophilic dye FM1-43 reaches intracellular membranes. This live assay also allows a sensitive assessment of the ability of exogenously added soluble factors such as sphingomyelinase to inhibit FM1-43 influx, reflecting the ability of cells to repair their plasma membrane. This assay allowed us to show for the first time that sphingomyelinase acts downstream of Ca2+-dependent exocytosis, since extracellular addition of the enzyme promotes resealing of cells permeabilized in the absence of Ca2+.

Live Imaging Assay for Assessing the Roles of Ca2+ and Sphingomyelinase in the Repair of Pore-forming Toxin Wounds

Live imaging of cells exposed to the lipophilic dye FM1-43 allows precise determination of the kinetics by which pore-forming toxins are removed from the plasma membrane. This is a sensitive assay that can be used to assess requirements for Ca2+, sphingomyelinase and other factors on plasma membrane repair.

يعيش التصوير الفحص لتقييم أدوار كا<sup&gt; 2 +</sup&gt; وSphingomyelinase في إصلاح مسام تشكيل الجروح السمية

Plasma membrane injury is a frequent event, and wounds have to be rapidly repaired to ensure cellular survival. Influx of Ca2+ is a key signaling event ...

Chitosan/Interfering RNA Nanoparticle Mediated Gene Silencing in Disease Vector Mosquito Larvae

Vector mosquitoes inflict more human suffering than any other organism&#8212;and kill more than one million people each year. The mosquito genome projects facilitated research in new facets of mosquito biology, including functional genetic studies in the primary African malaria vector Anopheles gambiae and the dengue and yellow fever vector Aedes aegypti. RNA interference- (RNAi-) mediated gene silencing has been used to target genes of interest in both of these disease vector mosquito species. Here, we describe a procedure for preparation of chitosan/interfering RNA nanoparticles that are combined with food and ingested by larvae. This technically straightforward, high-throughput, and relatively inexpensive methodology, which is compatible with long double stranded RNA (dsRNA) or small interfering RNA (siRNA) molecules, has been used for the successful knockdown of a number of different genes in A. gambiae and A. aegypti larvae. Following larval feedings, knockdown, which is verified through qRT-PCR or in situ hybridization, can persist at least through the late pupal stage. This methodology may be applicable to a wide variety of mosquito and other insect species, including agricultural pests, as well as other non-model organisms. In addition to its utility in the research laboratory, in the future, chitosan, an inexpensive, non-toxic and biodegradable polymer, could potentially be utilized in the field.

Here we describe a procedure for inhibiting gene function in disease vector mosquitoes through the use of chitosan/interfering RNA nanoparticles that are ingested by larvae.

الشيتوزان / التدخل RNA الجسيمات النانوية وساطة جين إسكات في الأمراض ناقل يرقات البعوض

Vector mosquitoes inflict more human suffering than any other organism&#8212;and kill more than one million people each year. The mosquito genome projects ...

Meiotic Spindle Assessment in Mouse Oocytes by siRNA-mediated Silencing

Errors in chromosome segregation during meiotic division in gametes can lead to aneuploidy that is subsequently transmitted to the embryo upon fertilization. The resulting aneuploidy in developing embryos is recognized as a major cause of pregnancy loss and congenital birth defects such as Down&#8217;s syndrome. Accurate chromosome segregation is critically dependent on the formation of the microtubule spindle apparatus, yet this process remains poorly understood in mammalian oocytes. Intriguingly, meiotic spindle assembly differs from mitosis and is regulated, at least in part, by unique microtubule organizing centers (MTOCs). Assessment of MTOC-associated proteins can provide valuable insight into the regulatory mechanisms that govern meiotic spindle formation and organization. Here, we describe methods to isolate mouse oocytes and deplete MTOC-associated proteins using a siRNA-mediated approach to test function. In addition, we describe oocyte fixation and immunofluorescence analysis conditions to evaluate meiotic spindle formation and organization.

Here, we present a protocol for specific siRNA-mediated mRNA depletion followed by immunofluorescence analysis to evaluate meiotic spindle assembly and organization in mouse oocytes. This protocol is suitable for in vitro depletion of transcripts and functional assessment of different spindle and/or MTOC-associated factors in oocytes.

تقييم المغزل الانتصافي في ماوس البويضات التي كتبها بوساطة سيرنا إسكات

Errors in chromosome segregation during meiotic division in gametes can lead to aneuploidy that is subsequently transmitted to the embryo upon ...

Simultaneous Measurement of Mitochondrial Calcium and Mitochondrial Membrane Potential in Live Cells by Fluorescent Microscopy

Apart from their essential role in generating ATP, mitochondria also act as local calcium (Ca2+) buffers to tightly regulate intracellular Ca2+ concentration. To do this, mitochondria utilize the electrochemical potential across their inner membrane (&#916;&#936;m) to sequester Ca2+. The influx of Ca2+ into the mitochondria stimulates three rate-limiting dehydrogenases of the citric acid cycle, increasing electron transfer through the oxidative phosphorylation (OXPHOS) complexes. This stimulation maintains &#916;&#936;m, which is temporarily dissipated as the positive calcium ions cross the mitochondrial inner membrane into the mitochondrial matrix.
We describe here a method for simultaneously measuring mitochondria Ca2+ uptake and &#916;&#936;m in live cells using confocal microscopy. By permeabilizing the cells, mitochondrial Ca2+ can be measured using the fluorescent Ca2+ indicator Fluo-4, AM, with measurement of &#916;&#936;m using the fluorescent dye tetramethylrhodamine, methyl ester, perchlorate (TMRM). The benefit of this system is that there is very little spectral overlap between the fluorescent dyes, allowing accurate measurement of mitochondrial Ca2+ and &#916;&#936;m simultaneously. Using the sequential addition of Ca2+ aliquots, mitochondrial Ca2+ uptake can be monitored, and the concentration at which Ca2+ induces mitochondrial membrane permeability transition and the loss of &#916;&#936;m determined.

Mitochondria can utilize the electrochemical potential across their inner membrane (&#916;&#936;m) to sequester calcium (Ca2+), allowing them to shape cytosolic Ca2+ signaling within the cell. We describe a method for simultaneously measuring mitochondria Ca2+ uptake and &#916;&#936;m in live cells using fluorescent dyes and confocal microscopy.

قياس وقت واحد من الميتوكوندريا الكالسيوم والميتوكوندريا غشاء المحتملة في الخلايا الحية التي كتبها نيون الميكروسكوب

Apart from their essential role in generating ATP, mitochondria also act as local calcium (Ca2+) buffers to tightly regulate intracellular Ca2+ ...

Monitoring ER/SR Calcium Release with the Targeted Ca2+ Sensor CatchER+

Intracellular calcium (Ca2+) transients evoked by extracellular stimuli initiate a multitude of biological processes in living organisms. At the center of intracellular calcium release are the major intracellular calcium storage organelles, the endoplasmic reticulum (ER) and the more specialized sarcoplasmic reticulum (SR) in muscle cells. The dynamic release of calcium from these organelles is mediated by the ryanodine receptor (RyR) and the inositol 1,4,5-triphosphate receptor (IP3R) with refilling occurring through the sarco/endoplasmic reticulum calcium ATPase (SERCA) pump. A genetically encoded calcium sensor (GECI) called CatchER was created to monitor the rapid calcium release from the ER/SR. Here, the detailed protocols for the transfection and expression of the improved, ER/SR-targeted GECI CatchER+ in HEK293 and C2C12 cells and its application in monitoring IP3R, RyR, and SERCA pump-mediated calcium transients in HEK293 cells using fluorescence microscopy is outlined. The receptor agonist or inhibitor of choice is dispersed in the chamber solution and the intensity changes are recorded in real time. With this method, a decrease in ER calcium is seen with RyR activation with 4-chloro-m-cresol (4-cmc), the indirect activation of IP3R with adenosine triphosphate (ATP), and inhibition of the SERCA pump with cyclopiazonic acid (CPA). We also discuss protocols for determining the in situ Kd and quantifying basal [Ca2+] in C2C12 cells. In summary, these protocols, used in conjunction with CatchER+, can elicit receptor mediated calcium release from the ER with future application in studying ER/SR calcium related pathologies.

Monitoring ER/SR Calcium Release with the Targeted Ca2+ Sensor CatchER+

We present protocols for the application of our targeted genetically-encoded calcium indicator (GECI) CatchER+ for monitoring rapid calcium transients in the endoplasmic/sarcoplasmic reticulum (ER/SR) of HEK293 and skeletal muscle C2C12 cells using real-time fluorescence microscopy. A protocol for the in situ Kd measurement and calibration is also discussed.

رصد إير / سر إطلاق الكالسيوم مع الكالسيوم المستهدفة<sup&gt; 2+</sup&gt; الاستشعار الماسك<sup&gt; +</sup

Intracellular calcium (Ca2+) transients evoked by extracellular stimuli initiate a multitude of biological processes in living organisms. At the center of ...

Analysis of Beta-cell Function Using Single-cell Resolution Calcium Imaging in Zebrafish Islets

Pancreatic beta-cells respond to increasing blood glucose concentrations by secreting the hormone insulin. The dysfunction of beta-cells leads to hyperglycemia and severe, life-threatening consequences. Understanding how the beta-cells operate under physiological conditions and what genetic and environmental factors might cause their dysfunction could lead to better treatment options for diabetic patients. The ability to measure calcium levels in beta-cells serves as an important indicator of beta-cell function, as the influx of calcium ions triggers insulin release. Here we describe a protocol for monitoring the glucose-stimulated calcium influx in zebrafish beta-cells by using GCaMP6s, a genetically encoded sensor of calcium. The method allows monitoring the intracellular calcium dynamics with single-cell resolution in ex vivo mounted islets. The glucose-responsiveness of beta-cells within the same islet can be captured simultaneously under different glucose concentrations, which suggests the presence of functional heterogeneity among zebrafish beta-cells. Furthermore, the technique provides high temporal and spatial resolution, which reveals the oscillatory nature of the calcium influx upon glucose stimulation. Our approach opens the doors to use the zebrafish as a model to investigate the contribution of genetic and environmental factors to beta-cell function and dysfunction.

Beta-cell functionality is important for blood-glucose homeostasis, which is evaluated at single-cell resolution using a genetically encoded reporter for calcium influx.