Kun:LabNotes/Haplotyping/2010-8-19: Difference between revisions
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==Results== | ==Results== | ||
*The concentration of HMW gDNA seems to be under-estimated by 10-fold. Amplification curves came up faster than those from pure gDNA. | *The concentration of HMW gDNA seems to be under-estimated by 10-fold. Amplification curves came up faster than those from pure gDNA. | ||
* | *The concentration of chrL seems to be slightly over-estimated (<2-fold). Amplicons 2E&2F were likely amplified from a subset of chromosomes. | ||
*The concentration of chrS seems to be under-estimated (~5-fold). Amplicons 1F/1G were likely amplified from a subset of chromosomes. | |||
*What to do next? Purify 1F/1G/2E/2F, shear and make bar-coded Illumina libraries. Sequence all four libraries in one lane (could be mixed with other compatible libraries). |
Revision as of 22:30, 20 August 2010
Whole chromosome MDA
- Objective: in this experiment, I will try to amplify haploid human chromosomes with MDA.
- Will try on both chromosomes in highly condense form (chr.S) and loosely packed chromosomes (chr.L).
- Will do protease digestion to disrupt the chromosome structure.
- Will compare metaphase chromosomes with cell lysates that contain high molecular weight gDNA.
- Will also use purified gDNA as control.
- Number of reactions:
1 chr 10 chrs 100 chrs chr.S x 4 x 4 x 2 chr.L x 4 x 4 x 2 0.6pg 3pg 30pg NTC HMW gDNA x 4 x 4 x 2 Pure gDNA x 2 x 2 x 2 x4
Prepare Alkaline Lysis Solution (ALS) and Neutralization Solution (NS)
- I'll make these solutions using the DLB and Stop solution from Qiagen's Repli-g kit.
- Add 500ul RT-PCR grade water to the DLB tube.
- Add 10ul DLB solution into 70ul RT-PCR grade water. Split into 4 tube (20ul/tube).
- Add 8ul Stop solution into 72ul RT-PCR grade water. Split into 4 tubes (20ul/tube).
- Perform UV treatment on the solutions for 5 minutes.
Whole cell lysates
- Yesterday I collected ~3 millions GM20431 cells (442,000/ml x 6.8ml), and lysed them with 200ul Cell Lysis Buffer (20M EDTA, 10mM Tris.HCl , 200mM NaCl, 0.2% Triton X-100, 0.1AU/ml Qiagen Protease).
- The resulting cell lysate is extremely sticky. I added 800ul EB buffer, still quite sticky. The DNA concentration is roughly 18ug per ml or 18ng/ul.
- Take 20ul, add 100 UV-treated water -> 3ng/ul;
- Make 1:10 serial dilution to 300pg/ul, 30pg/ul, 3pg/ul and then 1:5 dilution to 0.6pg/ul. Pipette slowly to avoid breaking HMW DNA.
Set up MDA reactions
- MDA
Mix 1ul template with 1ul ALS buffer, RT for 3min Add 2ul NS buffer Add 10ul PNP (Primer-nucleotide-protease) buffer 10x RepliPhi Buffer 1.4ul 1mM N6 primer 1.0ul 25mM dNTP 0.8ul 0.05AU/ml Protease 0.5ul H2O 6.5ul 37C 30min -> 70C 15min -> 4C hold Add 6ul ED (Enzyme-Dye) buffer 10x RepliPhi Buffer 0.6ul 2X SYBR Green I 1.0ul RepliPhi Phi29(100U/ul) 1.0ul H2O 3.4ul Incubate at 30C for 4h on Opticon4, take one read every 6 minutes.
Results
- The concentration of HMW gDNA seems to be under-estimated by 10-fold. Amplification curves came up faster than those from pure gDNA.
- The concentration of chrL seems to be slightly over-estimated (<2-fold). Amplicons 2E&2F were likely amplified from a subset of chromosomes.
- The concentration of chrS seems to be under-estimated (~5-fold). Amplicons 1F/1G were likely amplified from a subset of chromosomes.
- What to do next? Purify 1F/1G/2E/2F, shear and make bar-coded Illumina libraries. Sequence all four libraries in one lane (could be mixed with other compatible libraries).