C******8 发帖数: 602 | 1 可不可以用5x promega passive lysis dilute到1x以后的lysis buffer裂解细胞然后
做western blot或者IP呀?
那个lysis buffer本来是用来测luciferase assay的,我看裂解细胞效果蛮好。不知道
应用在其它地方是不是可以
谢谢 |
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m*********n 发帖数: 158 | 2 endogenous protein pulldown,以前都是harvest cell lysis,然后antibody incubation overnight, next day add
beads for 1-2hours, and pulldown
听说把beads先和antibody cross link一下,可以提高pulldown efficiency;
所以准备把antibody-bead cross link,加到cell lysis,这样得话,大家一般incubate
在cell lysis里面多久呀?
谢谢 |
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s********n 发帖数: 2939 | 3 Then I moved to culture more and lysed the cells using a sonicator, after
resuspending the pellet with 1x cold PBS/1% PI. After all these, I loaded
the supernatant and pellet side by side and stained by GelCode and a bulk of
protein (I assume it was protein) was detected in the pellet part.
你有没有在supernatant中检测到你的target protein?如何检测的?WB or activity?
从你的表述你好像没有做WB。
Then I tried 1L culture and repeated the 2nd experiment. This time, I
incubated the supernatant with glutathione sepharose 4b beads an... 阅读全帖 |
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s********x 发帖数: 472 | 4 做了多年的protein,一直都是直接把sample冻在-80,用的时候再lysis。
以为这样组织起码没有受到大的破坏。
但是最近一个同事说应该先lysis,因为buffer里面有各种inhibitor,所以更保险。
不知道有没有哪位大牛知道到底哪种方式比较好。
有没有什么可靠的文献研究?
Thanks! |
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f*****f 发帖数: 195 | 5 以前一直是bradford测浓度来保证loading一致。cell lysis buffer含NP40,DTT等。
两个样品A595差得比较远时比如0.4和0.1,线性不是很好,感觉定量不是很准。
另外,测A595(普通分光光度计)时,cell lysis加入到Bradford 1 min后测量和20
min后测量读数差别挺大的。
最近用nanodrop直接测A280同一个样品,不同时候测variation要比bradford小得多。
而且同一个样品,线性也挺好的,而且样品比较多的时候,比bradford方便。
根据A280来loading control,进而比较同一细胞系不同处理或比较不同细胞系有问题
么?你们平时一般用什么定量?谢谢。 |
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s******y 发帖数: 28562 | 6 This is a convenient recipe: 0.5% Triton X-100, 20~50mM Hepes-KOH, pH 7.8,
50mM KCl, 2mM MgCl2, 5mM EGTA,1mM EDTA, 100mM Sucrose, Plus cocktail of
protease inhibitors.
Triton X-100 is for lysis of cell membrane, Sucrose is for the stablity of
most proteins, protease inhibitors is again proteolysis.
However, this may differe depend on your purpose. You should check related
reference to get a recipe that works for your experiment
By the way, in some recipe, I notice they don't use Triton, don't un |
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C******8 发帖数: 602 | 7 成分没写呀
就是写了
5x passive lysis buffer |
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a**v 发帖数: 406 | 8 It's OK to use for detecting cytoplasmic protein. It's not good for nuclear
protein since passive lysis buffer does not lyze nucleus. |
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n***w 发帖数: 2405 | 9 Hi, all,
I am using Rosetta-Gami DE3 pLySs to expression my fusion protein which is
predicted as 91kDa.
I first did the expression assay and found protein expression was induced
after adding IPTG by testing the whole cell lysate. (bacteria at certain
time points, add 2X sample buffer, boil, SDS-PAGE).
Then I moved to culture more and lysed the cells using a sonicator, after
resuspending the pellet with 1x cold PBS/1% PI. After all these, I loaded
the supernatant and pellet side by side and stain... 阅读全帖 |
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T**********t 发帖数: 1604 | 10 pLysS只表达少量的Lysozyme用于抑制T7 RNA polymerase,而且表达出来的lysozyme在
胞内而不是细胞外,无法作用在细胞壁上。所以在lysis buffer里加lysozyme是必需的。
只不过我觉得lysozyme对于inclusion body本身的溶解应该没什么作用吧,它的作用估
计只是让细胞降解的更彻底,释放出更多的inclusion body而已。
of |
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h**********r 发帖数: 671 | 11 没有买现成的E.coli的lysis buffer.网上看了看,多种多样的。大家给个自己用的比
较好的recipe吧。裂解完之后测酶活的。多谢了!
包子伺候。 |
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f*****f 发帖数: 195 | 12 拿细胞lysis做IP,假如不立即做的话,如下哪种好?
1 收集cell pellets后,LN2/-80
2 Lysisbuffer裂解后,LN2/-80 |
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w*******r 发帖数: 23 | 13 RT.
请问 IP 和 co-IP 的lysis buffer 可以通用吗?
这两个在实验操作过程中具体有什么区别呢?
谢谢。 |
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y****i 发帖数: 2194 | 14 温度是关键,一定要迅速降温,整个组织先扔到ice cold pbs里面冷却
然后再捞出来上lysis buffer
要是还不行 可以混用两种cocktail, roche+sigma, 各自用1x
还有就是如果只是western DTT, EDTA之类都可以招呼上 |
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z*********8 发帖数: 1203 | 15 我做过这个实验,用液氮ground tissue,然后加点buffer,直接hypotonic lysis了,
感觉效果还可以,不过我整体感觉tissue尤其是gut里面protease, RNAase都比较高。 |
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d****i 发帖数: 2346 | 16
我是从液氮里直接拿出来的,扔进lysis buffer。。。 |
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d****i 发帖数: 2346 | 17
你的意思是先研成干粉,然后加lysis buffer? |
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s******y 发帖数: 28562 | 18 以前我都是这么做的。先在液氮浸泡里磨成干粉,然后直接加lysis buffer煮了。 |
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D**A 发帖数: 311 | 19 protease inhibitor 加够推荐的量就可以,多加浪费钱,效果还不一定好,可以加点
PMSF, benzamidine, EDTA之类的便宜inhibitor, 隔1-2小时补加一次就可。15%
glycerol.
先用液氮冷,然后快速解冻, 加冷的lysis buffer试试。
蛋白在室温下过夜会水解。
能想到的就这么多了。 |
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d****i 发帖数: 2346 | 20
非常感谢!我也是实在没办法,多加了inhibitor。PMSF也加了。
加了inhibitor的lysis buffer放在冰里遇冷,然后从液氮里拿出tissue,立即
homogenize。。。。
我说的室温过夜是加了6xloading buffer,另外我的buffer里还有2%的SDS,这样也会
降解吗? |
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e****s 发帖数: 1125 | 21 我觉得Braford好很多。A280对成分巨多的lysis buffer和混合蛋白不可能准确,个人
认为干扰因素较大。
Bradford的话,通常Cell lysate的浓度是很高的,会有几百倍的稀释,NP40,DTT等的
影响就不大了。每次同做Standard line的话,1 min 或者20 min的incubation time影
响就不大了。 |
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h****k 发帖数: 182 | 22 lysis这一步的时候大家是怎么做的?刺激细胞之后有spin down吗,还是直接加lysis
buffer比较好?因为signal都很快出现,所以考虑直接加,但又不知道细胞体积和
lysis buffer体积比例怎样比较好。另外可以直接加loading buffer 不加lysis
buffer吗? |
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p*****r 发帖数: 64 | 23 多谢大家的建议.
aishang,我目前就想用机器先remove大部分的medium,剩下约8ul的medium (如果剩下的
medium太少的话,机器的tip头就会很容易带走细胞),然后多加一些lysis buffer.虽然
这样lysis buffer被稀释了,但可以试试能不能拿到足够的RNA.
ArtyArty: 我目前用的是Cell to CT kit, 它提供lysis buffer, stop buffer,裂解细
胞后,可以拿到RNA, 然后RT 后拿到cDNA.你能不能告诉我你知道的那个不用提RNA,就可
以做qPCR 的kit吗?十分感谢
smartkevin: 多谢你帮我查的plate, 我先打电话问问corning,看他们的这个plate怎么
work的,希望fit my story
目前这个实验是在broad做的,但broad里的人都用贴壁细胞,这样remove medium的时候,
细胞都不会少,所以他们对我的悬浮细胞也没什么好的建议.
多谢各位了. |
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j*****a 发帖数: 658 | 24 I am not sure if I understand you well...I thought the difference of non-
ionic (NP40, Triton X100) and ionic (SDS, sodium deoxycholate) is non-ionic
lysis buffer doesn't denature protein. Some of the antibody that recognizes
only non-denature antigen (original state, you might want to say) so that
you can't get good results if you use denature lysis buffer (SDS) with these
antibodies. In anothe word, non-denature lysis buffer is more safe. Am I
wrong?
So I am confused with what you said about "... 阅读全帖 |
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l********g 发帖数: 26 | 25 用高浓度NaCl是因为蛋白不是很稳定。
我是用M2-beads纯化的,说明书上直接推荐了一款产品作为lysis buffer,
我查了一下这种lysis buffer的盐浓度是150 mM,但是在这个浓度下我蛋白可能不稳定
。。
另外,我的lysis buffer还加了15%的甘油。
我新手,不是很清楚用flag tag纯化的时候需要注意什么。
还请大牛们指点指点 |
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s**********a 发帖数: 92 | 26 大家提取细胞蛋白的常用方法是哪个:
1,消化,离心,去上清,加 lysis buffer。
2,往皿中加 PBS,刮下来,离心,去上清,加 lysis buffer。
3,直接往皿中加 lysis buffer,刮下来,离心,取上清。
这 3 种方法对于最终的蛋白的质或量上有比较大的影响么?
我经常用 1 和 3,但好像我见过的说明书中,凡是涉及到收集细胞这块,一般都是用
的方法 2 。
谢谢! |
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k*****n 发帖数: 323 | 27 我们用的是rick young 的protocol。
Lysis Buffer 1 Add protease inhibitors just before use, filter and keep cold
. Consists of 50 mM HEPES-KOH, pH 7.5, 140 mM NaCl, 1 mM EDTA, 10% glycerol,
0.5% NP-40, 0.25% Triton X-100, 1× protease inhibitors Lysis Buffer 2 Add
protease inhibitors just before use, filter and keep cold. Consists of 10 mM
Tris-HCl, pH 8.0, 200 mM NaCl, 1 mM EDTA, 0.5 mM EGTA, 1× protease
inhibitors
Lysis Buffer 3 Add protease inhibitors just before use, filter and keep cold
. Consists of... 阅读全帖 |
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r******k 发帖数: 446 | 28 难道是dimer 没被lysis buffer打开??? 我用的是cell fractionation 用的 lysis
buffer 可能lysis不够强的原因吗? |
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s********n 发帖数: 26222 | 29 方舟子在此文中说“虫子不吃的, 人能吃吗”是中国人的质疑, 而美国人是不会问这
样的问题的, 这显然是骗人的。见下文和其中引用的文献, 其中不少是美国人的科研
。
"Comments on the human health impact of Bacillus thuringiensis toxin gene
product in genetically modified crops"
EPA Review Docket Number OPP-00678B
Professor Joe Cummins
Professor Emeritus of Genetics
University of Western Ontario
I have studied the Environment Protection Agency (EPA) document "Bt Plant-
Pesticides Biopesticides Registration Action Document B. HUMAN HEALTH
ASSESSMENT" and comment in the following ... 阅读全帖 |
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r****o 发帖数: 105 | 30 1. 一般LYSIS BUFFER里头SDS的浓度比较低,最多只有1%,所以
不至於让蛋白质变性,破坏正常的结合能力。不过很难讲,你要
试试。如果你要用lysate做enzyme assay,那就最好不要用SDS,因为
会降低酶活性。
2. 不太清楚,常规的LYSIS BUFFER并不一定需要Sodium fluoride.
查了一下,NaF好像是一种phosphatase的抑制剂。
3. 选择HEPES还是TRIS主要是看在特定pH 附近的缓冲能力。HEPES
是一种酸,用它配pH从5到7.5都还可以,再偏硷性,比如到8,就不是
很好了。TRIS则是一种硷,Pka比HEPES大,配pH8到7之间的缓冲液,
还可以,再偏酸性就不合适了。
如果你要做crosslinking,并且用的是amine coupling的crosslinker,
就不能用TRIS,因为TRIS分子有四个氨基,很容易与crosslinker发生
耦联。
4. 非离子型去垢剂,Nonidet P-40 是最温和的一种。 Triton X-100
也可以。
5. 不太清楚,但是我觉得问题不大。只要你保 |
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b********i 发帖数: 73 | 31 Not sure why you have to use SDS-free lysis buffer. I assume that someone
told you, maybe your PI, right?
1% SDS lysis buffer is quite standard. If you do not have specific reason
to avoid it, such as studying
chromatin binding complex, 1% SDS is fine for most of transfection factor
binding studies.
deoxycholate |
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s*****g 发帖数: 7857 | 32 cell signaling # 9803
Cell Lysis Buffer (10X)
____________
1X Cell Lysis Buffer:
20 mM Tris-HCl (pH 7.5)
150 mM NaCl
1 mM Na2EDTA
1 mM EGTA
1% Triton
2.5 mM sodium pyrophosphate
1 mM b-glycerophosphate
1 mM Na3VO4
1 μg/ml leupeptin
adding 1 mM PMSF immediately before use. |
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s********x 发帖数: 472 | 33 We met similar problem before, later we foundit by simply using more lysis
buffer, such as triple the quantity would solve the problem.
The lysis process is much less efficient in large system. |
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A******y 发帖数: 2041 | 34 I don't know what kit you are using, but I know there is a kit that allow
you to run RT-PCR in high-throughput without really isolating RNA (I think
you are doing this right?) If it is, extra media just there to interfere
with the lysis buffer. You don't have to remove it all just enough to lyse
the cells. I know someone almost patented the whole cell one step RT-PCR
technique but didn't.
Look at how the kit works and see if it make sense to you. So you added the
lysis buffer and then the on |
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m*****u 发帖数: 15526 | 35 我提核蛋白。lysis buffer里有0.4M NaCl, 10%glycerol。感觉对BCA法测量干扰很大。空白的
lysis buffer测出的值就很高。有什么别的办法可以解决么? |
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f*********r 发帖数: 1233 | 36 这是个典型的例子,即便别人给了protocol,仍然不能重复。
几点建议:
1,DNase能不用就先不用。
2,loading buffer里先不要加bromophenol blue。或者不要加太多。至少要清亮,能
看到里面是透明还是混浊还是沉淀。
或者可以先用lysis buffer,处理完了再加浓缩的loading buffer。
3,pellet加上lysis buffer以后,不要用pipette打匀。而是直接用sonication冲击。
sonication是很强的,别说一个pellet,就是坚韧的大块骨骼肌组织,都能轻易打碎。
确认pellet被彻底打散并溶解了。
4,打碎以后离心,如果不理想可以考虑超高速离心。
5,取上清(这个时候应该一点都不粘了),加loading buffer,煮,跑胶。
6,如果条带形状扭曲,可以考虑把running buffer里面的tris含量酌情加量(2-3倍,
只要低分子量的蛋白仍然跑得开,跑不开的可以用4-20%的胶)。
7,如果还不太理想,可以考虑弃用glycin running buffer,改用taurin running
buff... 阅读全帖 |
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m**z 发帖数: 787 | 37 run gel on the following samples: -IPTG, +IPTG, lysis supernatant, lysis
pellet.
If you have protein in +IPTG sample, then if it is mostly in pellet, that
tells you the solubility in this buffer is probably not great. |
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n**8 发帖数: 221 | 38 本人分子生物学菜鸟。。。
在做RNA-IP, 想用特异性的抗体把一个细胞核内的蛋白(RBP)binding的RNA pulldown
下来,
试过几种buffer,但是都不理想,
用过RIPA buffer 虽然可以IP到目标蛋白, 但是好像RBP-RNA complex 被打散了。RNA
没有被
IP下来。。。
2006年的两篇Nat protocol 文章用到Polysome lysis buffer去IP RNA。
(Peritz et al., 2006; Keene et al., 2006).我也试了一下,发现目标蛋白没能IP下
来,
连IP input WB 也detect不到这个RBP, 猜测lysis条件可能太gentle了,核膜没有破。
请教有RIP经验的大侠,有没有其他的好用的RIP buffer?
Any suggestions are appreciated!
不甚感激! |
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h**********r 发帖数: 671 | 39 以前做Neurospora的knockout的时候,看到过yeast方面的protocol。感觉他们挺严谨
的。但我不保证work。摘自:
http://www.dartmouth.edu/~neurosporagenome/Projects_files/Proje
Prepare yeast DNA with the Gentra yeast DNA kit:
(the following is slightly modified from their protocol:
http://www.gentra.com/pdf/01160.pdf)
the solutions are available from Gentra as Puregene kit D-6000A or
separately; if you have their Puregene solutions for Neurospora DNA preps,
you only need to order the Cell Suspension Solution (D-6001) and Lytic
Enzyme Sol... 阅读全帖 |
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h**********r 发帖数: 671 | 40 同上另外一种方法。
Yeast “smash-and-grab” DNA prep:
• pipette 1-2 ml YPD onto transformation plate; scrape colonies off
with the end of a glass slide and pipette into a microfuge tube
• spin down 15 sec; pipette off sup; if cell pellet is more than 50-75
μl, remove excess and discard
• to cell pellet add 0.2 ml lysis buffer, 0.2 ml phenol/CHCl3 and 0.3
g 0.45-0.5 mm glass beads* (I use calibrated scoop made from cut microfuge
tube pierced with syringe needle) – seal carefully because be... 阅读全帖 |
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b******r 发帖数: 111 | 41 Note: NHEs is membrane proteins that transmembrane 12 times. NHE5 is
localized to the plasma membrane;NHE6-9 reside on organellar membranes(
endosome,Golgi);
1. pcDNA transfects NHE5-9 through Fugene 6(ratio is 3 uL of Fugene/2 ug of
DNA) in 293 cells. After three days,collect cells.
2. Cold PBS washes cells. Add 150 uL of lysis buffer(final concentration:
50mM Tris pH7.4, 150mM NaCl, 1% triton, 0.1% sds, cocktail inhibitor)
into each well of 6-well plate. Scrape cells.
3. The lysate gets st... 阅读全帖 |
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W*********n 发帖数: 775 | 42 please help me to have a look at the whole protocols and give some
suggesitons:
1) get 50midguts (about 3000cells/midgut, so about 1,500,000 cells or 80ug
protein totally),add 80ul lysis buffer (8M Urea, in 1XPBS, pH=8) including
Protease inhibitor and phosphatase, ultrasonic for 15-30 sec, then votex for
1 min. centrifuge for 10min at 14,000g and take the supernatant, add 16ul
5X loading buffer and heat for 20--30 min at 60 degree. load gel at 30ul/
lane and run for 2cm(for each sample, run th... 阅读全帖 |
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c********b 发帖数: 363 | 43 每个步骤都是别人都知道的,我只是组装了一下. 最大不同是别人是先Urea变性,提出来
再复性.我是利用Triton X-100可以洗脱SDS的特点利用SDS变性,然后Triton X100洗脱
复性,然后过柱. 肯定不会对所有蛋白适用,但是起码我遇到的都work (包括一个>100
Kd的酶).
我是用的sonication water bath, 也可以用probe sonication再加SDS,都OK,但是注意
dilution的比例和体积.
Good luck. 用的高兴分我几个包子.
Key, keep a fraction from every step for analyses and trouble shooting
- Culture the E. coli overnight
- Induce it at a proper concentration of IPTG, room temperature for ~
4hrs
- Pellet the E. coli at 6000 rpm at 4 degree
- R... 阅读全帖 |
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n********k 发帖数: 2818 | 44 more buffer and complete and fast lysis will do it...For a beginner, do
yourself a favor and NEVER try to save on buffer---the key is complete
lysis with enough buffer...then it can last fairly long, as long as it is fully lysed, no worry about RNase until the column step...if in doubt, use
RNAlater...it is fantastic...
RLT |
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S******e 发帖数: 393 | 45 谢谢!
我做了两次,基本是一致的结果,目前还在做。
用的是sigma的M2 flag agarose beads,
600-1000ug总蛋白做IP,pre-clearance with IgG beads for 3hrs,
add flag beads, 4度rotate for 5hrs,
wash 3 times with lysis buffer,
then wash once with high salt(500mM NaCl) lysis buffer,
final wash with TBS,
SDS sample buffer elute(下次准备用flag peptide elute)
还请多指教。
domain
affinity |
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j****t 发帖数: 1663 | 46 Sonicator的功率是否够强?
SDS加得够吗?
可以试一下这个lysis buffer:
Lysis Buffer:
Consists of 10 mM Tris-HCl, pH 8.0, 100 mM NaCl, 1 mM EDTA,
0.5 mM EGTA, 0.1% Na-Deoxycholate, 0.5% N-lauroylsarcosine, 1× protease
inhibitors
建议follow几个nature protocol 的文章试试! |
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n******2 发帖数: 971 | 47 No, my sonicating buffer is slightly different from lysis buffer.
They both contain low concentration of Tris, NaCl, MgCl2, CaCl2, however,
sonicating buffer consists of higher amount of IGEPAL4% (compare to 0.5% in
lysis B) and 0.8% SDS.
I'm following the protocol developed by Affymatrix. It worked well on mouse
cells performed by another lab, but bothers me very much on my human cell
line. |
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j****t 发帖数: 1663 | 48 我是在这个lysis buffer里作sonication的。我现在用0.2% sarkosyl(instead of 0.
5%),和 1% of Na-deoxycholate。sonication的效果很好。而且这个浓度的detegent
对于IP 来说还是高了些,我会在做IP前把sample稀释一倍。
我觉得你的lysis和sonication 的条件也许可以了,问题说不定是在reverse-
crosslink。我的快速检测片段大小和ChIP DNA浓度的步骤如下,供你参考参考。
Check chromatin size and conc.
1. Dilute 50 ul chromatin extracts with 50 ul TE buffer. Add 4 ul of 5 M
NaCl and 1 ul of 10 mg/ml Proteinase K (Invitrogen #25530-015) (use a PCR
tube).
2. Incubate at 65 oC for at lease 4 hr (using a PCR machine) ... 阅读全帖 |
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c********r 发帖数: 189 | 49 用的是Bethyl的抗体,做co-IP,研究的蛋白A主要bind到chromatin上。
用bethyl的方法做的cell lysis, 然后co-IP,work。但是我发现,他们的lysis
buffer太mild,A蛋白主要还是留着pellet中。所以IP下来的只是一小部分,可能是
在cytoplasmic里的A蛋白
于是同时用nuclear extract来做co-IP,input里有很多A蛋白,但是co-IP不work,A蛋白没有pull down下来
所以问题是,为啥同一个antibody,可以pull down cyto fraction里的蛋白A,而不可以pull down nuclear内的蛋白A?
我的解释是,在nuclear extract里,A跟很多蛋白结合,于是antigen被mask了。。。
不知道还有没有别的解释
谢谢各位了 |
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c********r 发帖数: 189 | 50 用的是Bethyl的抗体,做co-IP,研究的蛋白A主要bind到chromatin上。
用bethyl的方法做的cell lysis, 然后co-IP,work。但是我发现,他们的lysis
buffer太mild,A蛋白主要还是留着pellet中。所以IP下来的只是一小部分,可能是
在cytoplasmic里的A蛋白
于是同时用nuclear extract来做co-IP,input里有很多A蛋白,但是co-IP不work,A蛋白没有pull down下来
所以问题是,为啥同一个antibody,可以pull down cyto fraction里的蛋白A,而不可以pull down nuclear内的蛋白A?
我的解释是,在nuclear extract里,A跟很多蛋白结合,于是antigen被mask了。。。
不知道还有没有别的解释
谢谢各位了 |
|