Lc3i and lc3ii as autophagy markers for the development and. The following protocol describes three simple and commonly used protocols for measuring autophagy in cells. Autophagy assays lc3b immunofluorescence, lc3b western blot, acridine orange assay. Lc3b monoclonal antibody western, immunoprecipitation. Two major proteolysis systems, the ubiquitinproteasome system, and the autophagylysosome system, contribute to degradation of. Figure 5 effects of drp1 inhibitor mdivi1 on mitochondrial autophagy, metabolism, and. Western blotting relies on the specific binding between the proteinofinterest and an antibody raised against this particular protein. The technique was named after its inventor, edward m. Alternate targets to study autophagy p62sqstm1structural domains relevant in. Lc3b targets observed by western blotting, which we predicted to be. Transfer gel into a pvdf membrane as the standard western blot protocol.
Set aside 200 ml for inner chamber add 500 l nupage antioxidant no more than 30 min before electrophoresis. Antilc3b antibody autophagosome marker ab48394 abcam. Upon autophagy induction lc3b, expressed in most cell types as a fulllength cytosolic protein, is proteolytically cleaved by atg4 to generate lc3bi. The blot is a membrane, almost always of nitrocellulose or pvdf polyvinylidene fluoride. Western blot protocol protocol specific for lc3 antibody. The mammalian homolog of atg8 is called microtubuleassociated proteins 1a1b light chains 3alc3a and 3b lc3b, abbreviated to lc3. We have purchased a new and fresh antibody against lc3 12000. Upon autophagy induction lc3b, expressed in most cell types as a fulllength cytosolic protein, is proteolytically cleaved by atg4 to generate lc3b i.
Lc3b immunofluorescence, western blot and acridine orange assay. Block the pvdf membrane in tbstween tbst with 5% nonfat dry milk for 1 h at. Lc3b specific antibody rabbit polyclonal from proteintech validated in western blot wb, immunohistochemistry ihc, immunofluorescence if, flow cytometry fc, enzymelinked. In some cases specific recommendations are provided on product datasheets, and these methods. Polyclonal antibody for studying lc3b in the autophagy signaling research area. M chloroquine overnight serve as a positive control.
Western blot analysis of extracts from hela cells, mock transfected or transfected with rat lc3b. Western blotting using polyvinylidene difluoride pvdf membranes. Assessment of macroautophagy following eto treatment day 4. Weigh certain amount of tissues and chop them into small pieces 3. This article is published with open access at abstract chemiluminescent western blotting. For primary ant ibodies rec ommended f or wes t ern blot t ing applic at ions, we rec ommend inc ubat ing t he membrane wit h dilut ed ant ibody at 4 c wit h gent le s hak ing ov ernight. Western blot blocking peptides dot blot immunohistochemistry immunofluorescence immunoprecipitation flow cytomety cell culture monocyte macrophage cells treated with. There was no evident localization in the nucleolar areas and in double immunofluorescence with lc3b there clearly lack of collocalizaton in the nucleoli and in the cytoplasm fig 4b. As previously mentioned, measurement of autophagic flux depends on the ability to distinguish between autophagosome formation and completion of autophagy through lysosome fusion and degradation. Southern, who developed the technique in edinburgh, scotland in the 1970s. I to detect lc3ii by western blot but its not working. I am using 80v90min to transferring lc3 from 12% sdspage to pvdf. Protein sample mixtures are first resolved by size using sodium dodecyl sulfate polyacrylamide gel electrophoresis sdspage. How can we detect lc3 ii band with western bloting.
Western blotting protocol cst cell signaling technology. Westernblotprotocoldelangelab western blot protocol updated on 052014 required solutions 10x pbs 1l 80 g nacl 2 g kcl 14. For western blots, incubate membrane with diluted primary antibody in either 5% wv bsa or nonfat dry milk, 1x tbs, 0. There was no evident localization in the nucleolar areas and in double immunofluorescence with lc3b there clearly lack of. Citations 926 flow cytometric analysis of hela cells using lc3b antibody blue compared to a nonspecific negative control antibody red. Reliable lc3 and p62 autophagy marker detection in. Western blot and immunofluores cence validated antibody specificity, knockdown efficiency and. Place the cell culture dish on ice and wash the cells with icecold pbs. Dilute the rabbit anti lc3b primary antibody nb60084 2 ugml in blocking buffer and incubate the membrane for 1 hour at room temperature. Antilc3b antibody produced in rabbit has been used in western blotting and immunohistochemistry. Lc3b antibody nb1002220 lc3b map1 nb1002220 detection of lc3 in mouse es cell lysates.
The ecl western blotting substrate detects picogram amounts of antigen, and with the use of photographic or other imaging methods, visualizes the presence of hrp. Western blot protocol protocol specific for lc3 antibody nb1002220 protocol. Western blot protocol for lc3b antibody nb60084 page 1 of 2. Judging from lc3b ii is peconjugated lc3b 1 and very lipophilic the sds might.
Here, we describe a method, suitable for monitoring flux in primary cells andor when reporters are not available or desirable, that uses lysosomal inhibitors and the analysis of endogenous lc3b ii the lipidated form of lc3b that is associated with autophagosomes by western blotting. Western blotting procedure the procedure for western blotting is as follows. Refer to table 1 for the effective range of separation of sdspage. P leas e ref er t o t he produc t s pec if ic prot oc ol f or our ant ibody diluent.
Protocols western blot complete western blot protocol phosphosolutions ultimate guide to doing western blots is broken down into 5 sections, containing a detailed list of steps, buffers, and specific materials needed within each section. Western blot data, both the protein of interest and loading control protein should fall within the linear range of detection. Lc3 is synthesized as prolc3 which is immediately processed by atg4 into a cytosolic form, lc3i. Prepare lc3b antibody by diluting it at 11,000 into abdiltw. Western blotting a beginners guide western blotting identifies with specific antibodies proteins that have been separated from one another according to their size by gel electrophoresis. Anti lc3b antibody produced in rabbit has been used in western blotting and immunohistochemistry. Recommended antigen amount and antibody dilution use in western blot. When autophagic flux is present or induced in a system an increase in the lc3b ii signal should be observed with the inhibitor.
Western blot analysis of extracts from hela cells, mock transfected or transfected with rat lc3b, and from ht1080 and a20 cells, untreated or chloroquinetreated 50. This assay measures the difference in the lc3b ii signal in the presence and absence of inhibitors e. Lc3b antibody nb1002220 lc3b map1 nb1002220 detection of lc3 in mouse es cell. General protocol for western blotting protein separation by gel electrophoresis 1. Dilute the rabbit anti lc3b primary antibody nb60084 2 ugml in blocking buffer and incubate the membrane for 1 hour. Western blots, two forms of lc3 are seen, lc3i and lc3ii. For amino acid analysis and protein sequencing of small amounts of proteins as little as 10 pmoles, electroblotting onto polyvinylidene difluoride pvdf membranes is ideal. Western blot analysis of lysates from nih3t3 cells, untreated or treated with chloroquine, using cleavedapg8a map1lc3acat. General western blot protocol sample lysis preparation of lysate from cell culture 1. E, f western blot analysis of lc3b lipidation in protein extracts from tibialis anterior muscles of untreated and i. Densitometric quantifications of lc3b ii vs lc3b i figure 8. Total cell extracts from hela cells treated with 50. Provided below are standard protocols that you may find useful for product applications.
Southern blotting is a method used to tran sfer dna from an agarose gel to a membrane, where the dna can be subsequently probed fo r a specific sequence. Recombinant antilc3b antibody epr18709 autophagosome. The western blot in the image was transferred overnight at constant voltage 30v. Please refer to the western blot protocol found on the product web. Western blot was performed from the immunoprecipitate using ab192890 at 1 dilution. A cartoon depicting protocol for measuring macroautophagic. Electrophoresis and western blot transfer systems 6. Western blot blocking peptides dot blot immunohistochemistry. Upon receipt, store antilc3 antibody and secondary antibody at 20. Always make fresh working solutions before isolation of proteins 1. The corresponding sequence differs by one aminoacid in rat and mouse. Our antibody is also validated for immunofluorescence. Western blot analysis showed a clear presence of lc3c in the nuclear fraction.
Tiled images are representative western blots against p62 top, lc3b. Other methods such as electron microscopy and immunofluorescence are also available to measure autophagy. Western blot protocol protocol specific for lc3 antibody nb100. Dilute 50x pi solution to 1x pi in tm buffer keeping the solution on ice 2. Lc3b antibody detects lc3b protein by western blot analysis. A laboratory manual, cold spring harbor laboratory, 1988. D representative western blot showing tumors with high and low levels of lc3b. I have learnt from few other people that getting bands for lc3 is a. A sponsored supplement to science sponsored by produced by the scienceaaas custom publishing office western blotting.
Inhibition of autophagy and lc3b antibody nb1002220 western blot. Western blot protocol protocol specific for lc3 antibody nb1002220 page 2 of 2. Veriblot for ip detection reagent hrp, was used for detection at 110,000 dilution. Inhibition of autophagy and lc3b antibody nb1002220. Western blot analysis of extracts from hela cells, untreated or chloroquinetreated 50. I dont have problems with the electrophoresis i think. Autophagosome proteins lc3a, lc3b and lc3c have distinct. Because many target proteins are expressed at low abundance relative to loading control proteins, large amounts of total protein are often loaded on the gel to accurately detect the target protein. Problems with my western blotting of lc3, autophagy protein. Autophagy assays lc3b immunofluorescence, lc3b western blot. As we are using the infrared detection system, blocking is done. Application anti lc3b antibody produced in rabbit has been used in. This lysate pair is produced as a control for western blotting of lc3a and lc3b. Dec 20, 20 other methods such as electron microscopy and immunofluorescence are also available to measure autophagy.
Block the pvdf membrane in tbstween tbst with 5% nonfat dry milk for 1 h at room temperature on a shaker. Autophagy immunoblot kit lc3ii detection cell biolabs, inc. In some cases specific recommendations are provided on product datasheets, and these methods should always be used in conjunction with product and batch specific information provided with each vial. Please follow current protocols on sdspage gel running and western transfer. I am trying to do western blot for lc3 and i cannot see any band for this protein, although i can see clear bands for atubulin. Chloroquine diphosphate cq 10 mm in dh2o 1x pbs sample buffer, 2x laemmli buffer. The blot should be on the cathode and the gel on the anode. Blots can be repeatedly exposed to xray film to obtain optimal results or stripped of the immunodetection reagents and reprobed. White arrowheads point at some gfplc3positive puncta. The antibody is superior for western blotting, detecting two bands at 1618 kda lc3i and 1416 kda lc3ii. Nov 28, 2011 request your western blot handbook today. I am a novice in this area, and i am having a great deal of trouble with western blotting.
I started to use pvdf for western blot recently to detect lc3. This paper highlights critical steps in the western blot protocol and demonstrates how protocol changes can affect the final outcome of your blot. The most straightforward and workhorse assay to measure autophagic flux is western blot immunoblot for lc3b i and ii 10, 20, 21. B representative time series analysis of circadian rhythms in macroautophagy in basal mouse liver. Lc3b was immunoprecipitated from 1 mg of hela human epithelial cell line from cervix adenocarcinoma whole cell lysate with ab192890 at 150 dilution. Lc3b i is activated by atg7 and then transferred to atg3 followed by conjugation to phosphatidylethanolamine pe to generate processed. This will be followed by the theoretical explanation of the procedure, and in the later section. These ubiquitinlike proteins can be used as reliable autophagosome markers for monitoring autophagy. Mitochondria are seen inside doublemembrane vesicles black arrows. Western blot analysis of lysates from a431 cell line, untreated or treated with chloroquine. Western blot the following protocol is an outline of a traditional western blotting protocol for the detection and characterization of a particular protein or biomolecule in a sample. Reasons to use the cell signaling technology western blotting protocol. Diurnal rhythms spatially and temporally organize autophagy. Normalized values of mir204 levels for each tumor are shown in a graph below the blot.
P leas e ref er t o t he produc t s pec if ic prot oc ol. Why am i not able to detect the lc3 band in western blotting. What is the appropriate voltage for transferring lc3 in western blot. Taylor thomas berkelman geetha yadav matt hammond the authors 20. Western blotting is an analytical immunoblotting technique to detect specific proteins in a cell extract or tissue homogenate. Measuring processing of endogenous lc3b by western blot is one of the most commonly used approaches to detecting increased autophagy in cells. The western blot technique is a powerful tool to elucidate the complex signaling events that underlie biological processes and. In addition, pvdf membranes can be used for immunoblotting western blot analysis. This western blot protocol provides a general procedure for use with the majority of biorad reagents. Monitoring autophagic flux by using lysosomal inhibitors and. Western blot protocol for lc3b antibody nb60084 page 2 of 2. Autophagy assays lc3b immunofluorescence, lc3b western. Human atg4 autophagy proteases counteract attachment of. In autophagy the staining pattern has been shown to change from diffuse to more punctate when lc3ii is bound to the autophagosome 3.
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