Sam:LabNotes/Human-Chip-bisulfite-Seq/2010-2-15 exp2
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Low-Input DNA libarary construction - Internal marker templates
Background
- Test low-input DNA libaray conscturction using internal marker at 200ng, 50ng, 10ng at 0ng, with or without De-P-carrier.
- Goals:
- Test the newly synthesized adaptors and primers by myself.
- Test Celso's protocol (with new End-repairing recipe).
- Get the reference position of post-ligation reactions from internal marker template.
- Compare the effect of adding De-P-carrier or not on library construction.
- Test the effect of contamination by De-P-carrier
Pocedures
- Prepare the following samples
- E.coli internal marker (IM) (200bp): 43.6ng/uL
- 1/10 dilutted E.coli internal marker (IM) (200bp): 4.36ng/uL
- DNAse digested-cleaned (D-C) tRNA 109 ng/uL
Sample name L1 L2 L3 L4 L5 L6 200ng IM 50ng IM 10ng IM 50ng IM 10ng IM 0ng IM 300ng tRNA 450ng tRNA 490ng tRNA 450ng tRNA 490ng tRNA 500ng tRNA ----------------------------------------------------------------------------------------------------------------- E.coli IM (43.6ng/uL) 4.59 1.146 - 1.146 - - 1/10 E.coli IM (4.36ng/uL0 - - 2.293 2.293 - D-C-tRNA (109ng/uL) 2.75 4.128 4.49 4.128 4.49 4.587 H2O 42.66 44.726 43.217 44.726 43.217 45.413 -------------------------------------------------------------------------------------------------------------- 100.00 100.00 100.00 100.00 100.00 100.00 uL NOTE: reactions L1, L2 and L3 will be added with De-P-carrier. Reactions L4, L5 and L6 won't.
Purify the DAN mixture with EtOH precipitation
- (mimic the real precedures to remove the enzyme and buffers from WGA reactions)
- Each sample (PCR product) has 100uL volume
- In a non-sticky 1.5-mL tube. Add 10uL 3M NaOAc, 250uL 100% EtOH, 1.5uL Glycoblue and 100uL DNA samples. Vortex 5sec.
- Incubation at 80C for 25min. Pelleting at 10,000xg 4C for 25min. Remove supernatant.
- Washing with 750uL 75%EtOH. Pelleting at 10,000xg 4C for 5min. Remove supernatant.
- Air dry the pellet. Dissolve the pellet in 34uL H2O.
End-reparing & Phosphorylation
- End-it Kit (EPICENTRE)
- Set up reactions on cold block
1rxn 6.5rxn DNA+H2O 34.0 - 10X buf. 5.0 32.5 2.5mM dNTP 5.0 32.5 10mM ATP 5.0 32.5 Enzyme 1.0 6.5 ------------------------------------ 50.0 104.0 104/6.5=16 --- DNA 34uL
- Mix the reaction by vortexing 5sec. Incubate at RT for 45min.
- During the incubation, set up QIAquick washing set and thaw the reagents for the following steps (A-tailing)
- No inactivation needed, but purify the blunted DNA with QIAquick column.
- After 45min incubation, add the product (50uL) into 1.5-mL non-sticky tube containg 250uL PB (QIAquick buffer)
- Adding De-P-Carrier into the DNA mixture
- Use De-P-Carrier "3"(100bp): 22uL*40ng/uL/30uL = 30ng/uL
- 450ng for L4 reaction: 450/30=15.0uL
- 490ng for L5 reaction: 490/30=16.3uL
- 500ng for L6 reaction: 500/30=16.6uL
(Vortex the DNA mixture and store the sample in -20C)
- Elute DNA in pre-warmed PB (20 + 8uL)
A-tailing
- Exo-minus klenow DNA pol. kit (Epicentre)
- Dilute the 100mM dATP to 1mM dATP
- Set up reactions on cold block
1rxn 6.5rxn DNA+H2O 28.0 - 10X buf. 4.0 26.0 1mM dATP 6.0 39.0 Enzyme 2.0 13.0 ------------------------------------ 40.0 78.0 78/6.5=12 --- DNA 28uL