Tag Archives: 1NF18

Agarose Gel – Oly gDNA for BS-seq Libraries, Take Two

The gel I ran earlier today looked real rough, due to the fact that I didn’t bother to equalize loading quantities of samples (I just loaded 1μL of all samples regardless of concentration). So, I’m repeating it using 100ng of DNA from all samples.

Additionally, this gel also includes C.gigas samples that Katie Lotterhos sent to us to see how they look.

Ran a 0.8% agarose, low-TAE gel, stained with ethidium bromide.



Look at that! The samples look MUCH nicer when they’re not overloaded and uniformly loaded!

Most have a prominent high molecular weight band (the band that’s closes to the top of the ladder, not the DNA visible in the wells). All exhibit smearing, but 2NF1 shows a weird accumulation of low molecular weight DNA.

Katie’s C.gigas samples (M1, M2, M3) look similar to the Olympia oyster gDNA, however her samples appear to have residual RNA in them (the fuzzy band ~500bp).

Will discuss with Steven which samples he wants to use for bisulfite treament and library construction.


Agarose Gel – Oly gDNA for BS-seq Libraries

Ran 1μL of each sample from yesterday’s DNA isolation on a 0.8% agarose, low-TAE gel, stained with ethidium bromide.





Since I didn’t load equal quantities of DNA, the intensities across the various samples is highly variable.

Those samples with high degree of smearing are also those with the highest concentrations. Thus, one would expect to be able to visualize a greater range of DNA sizes in a gel (because more DNA is present). Notice the samples with nice, high molecular weight bands and little smearing (1NF16, 1NF17). These are less than half the concentrations of all the samples that exhibit extensive smearing (2NF3, 2NF8, 1NF12). So, I think all samples will be fine for proceeding with bisulfite conversion and subsequent library construction.

However, I should re-run this gel using equalized DNA quantities for all samples…



DNA Isolation – Oly gDNA for BS-seq

Need DNA to prep our own libraries for bisulfite-treated high-throughput sequencing (BS-seq).

Isolated gDNA from the following tissue samples stored in RNAlater (tissue was not weighed) using DNAzol:


The sample coding breaks down as follows (see the project wiki for a full explanation):


2 = Oysters outplanted in Fidalgo Bay

NF = Broodstock originated in Fidalgo Bay

= Sample number


1 = Oysters outplanted in Oyster Bay

NF = Broodstock originated in Fidalgo Bay

= Sample number


DNA was isolated in the following manner:

  • Homogenized tissues in 500μL of DNAzol (Molecular Research Center; MRC).
  • Added additional 500μL of DNAzol.
  • Added 10μL of RNase A (10mg/mL, ThermoFisher); incubated 10mins @ RT.
  • Added 300μL of chloroform and mixed moderately fast by hand.
  • Incubated 5mins @ RT.
  • Centrifuged 12,000g, 10mins, RT.
  • Transferred aqueous phase to clean tube.
  • Added 500μL of 100% EtOH and mixed by inversion.
  • Pelleted DNA 5,000g, 5mins @ RT.
  • Performed 3 washes w/70% EtOH.
  • Dried pellet 3mins.
  • Resuspended in 100μL of Buffer EB (Qiagen).
  • Centrifuged 12,000g, 10mins, RT to pellet insoluble material.
  • Transferred supe to clean tube.

The samples were quantified using the Qubit dsDNA BR reagents (Invitrogen) according to the manufacturer’s protocol and used 1μL of sample for measurement.


Qubit data (Google Sheet): 20151216_Oly_gDNA_qubit_quants

2NF1 76.4
2NF2 175
2NF3 690
2NF4 11.7
2NF5 142
2NF6 244
2NF7 25
2NF8 456
1NF11 182
1NF12 432
1NF13 155
1NF14 21
1NF15 244
1NF16 112
1NF17 25.2
1NF18 278


Will run samples on gel tomorrow to evaluate gDNA integrity.