Tag Archives: NanoDrop1000

RNA Isolation – Geoduck Gonad in Paraffin Histology Blocks

UPDATE 20150528: The RNA isolated in this notebook entry may have been consolidated on 20150528.

The RNA isolation I performed earlier this week proved to be better for some of the samples (scraping tissue directly from the blocks), but still exhibited low yields from some samples. I will perform a final RNA isolation attempt (the kit only has six columns left) from the following samples:

  • 02
  • 03
  • 04
  • 07
  • 08
  • 09

Instead of full sections from each histology cassette, I gouged samples directly from the tissue in each of the blocks to maximize the amount of tissue input.

IMPORTANT:

Samples were then processed with the PAXgene Tissue RNA Kit in a single group.

Isolated RNA according to the PAXgene Tissue RNA Kit protocol with the following alterations:

  • “Max speed” spins were performed at 19,000g.
  • Tissue disruption was performed with the Disruptor Genie @ 45C for 15mins.
  • Shaking incubation step was performed with Disruptor Genie
  • Samples were eluted with 40μL of Buffer TR4, incubated @ 65C for 5mins, immediately placed on ice and quantified on the Roberts Lab NanoDrop1000.

 

All samples were stored @ -80C in Shellfish RNA Box #5.

Results:

 

Two samples (02 and 07) produced great yields and perfect RNA (260/280 and 260/230 of ~2.0). The remainder of the samples showed little improvement compared to what I’ve been obtaining from the previous three attempts. Will discuss with Steven and Brent about how to proceed with this project.

RNA Isolation – Jake’s O. lurida Ctenidia Control from 20150422

Isolated RNA from Jake’s Olympia oyster ctenidia, controls, collected on 20150422. Samples had been homogenized and stored @ -80C.

The following sample tubes (heat-shocked oyster ctenidia) were removed from -80C and thawed at RT:

  •  42215 HC 1
  •  42215 HC 2
  • 42215 HC 3
  • 42215 HC 4
  • 42215 HC 5
  • 42215 HC 6
  • 42215 HC 7
  • 42215 HC 8
  • 42215 NC 1
  • 42215 NC 2
  • 42215 NC 3
  • 42215 NC 4
  • 42215 NC 5
  • 42215 NC 6
  • 42215 NC 7
  • 42215 NC 8
  • 42215 SC 1
  • 42215 SC 2
  • 42215 SC 3
  • 42215 SC 4
  • 42215 SC 5
  • 42215 SC 6
  • 42215 SC 7
  • 42215 SC 8

 

NOTE: 0.1% DEPC-H2O used throughout this procedure was prepared on 7/15/2010 by me.

 

According to Jake’s notebook entry, the samples should have been previously homogenized in RNAzol RT (Molecular Research Center; MRC). However, none of the samples showed evidence of being homogenized:

 

 

 

Procedure:

Samples were homogenized with disposable pestle in their respective tubes and vortexed.

Added 400μL of 0.1% DEPC-H2O to each sample and vortexed 15s.

Incubated samples 15mins at RT.

Centrifuged tubes 15mins at RT @ 16,000g.

750μL of the supe was transferred to a clean tube, added equal volume of isopropanol (750μL), mixed by inversion (20 times), and incubated at RT for 15mins.

Centrifuged 12,000g for 10mins.

Discarded supe.

Washed pellets with 500μL of 75% EtOH (made with 0.1% DEPC-H2O) and centrifuged 4,000g for 3mins at RT. Repeated one time.

Removed EtOH and resuspended in 100μL of 0.1% DEPC-H2O. Most samples required vortexing to dissolve pellet.

Sample tubes were transferred to ice, quantified on the Roberts Lab NanoDrop1000, and stored @ -80C in their original box, pictured:

 

 

 

 

Results:

Google Spreadsheet with absorbance data: 20150507_Jake_Oly_control_RNA_ODs

 

Excellent yields and pretty solid 260/280 ratios (>1.85). Interestingly, the 260/230 ratios aren’t so great (compared to yesterday’s isolations). I suspect that the reason for this is that there appeared to be more starting tissue in these samples than yesterday’s. The greater quantity of tissue explains the higher yields and could be tied to the decrease in the 260/230 ratios…

Anyway, things look good. Next step will be to check for gDNA carryover in these samples and yesterday’s samples.

RNA Isolation – Jake’s O. lurida Ctenidia 1hr Heat Stress from 20150422

Isolated RNA from Jake’s Olympia oyster ctenidia, 1hr heat shock, collected on 20150422. Samples had been homogenized and stored @ -80C.

The following sample tubes (heat-shocked oyster ctenidia) were removed from -80C and thawed at RT:

  • 42215 HT1 1
  • 42215 HT1 2
  • 42215 HT1 3
  • 42215 HT1 4
  • 42215 HT1 5
  • 42215 HT1 6
  • 42215 HT1 7
  • 42215 HT1 8
  • 42215 NT1 1
  • 42215 NT1 1
  • 42215 NT1 2
  • 42215 NT1 3
  • 42215 NT1 4
  • 42215 NT1 5
  • 42215 NT1 6
  • 42215 NT1 7
  • 42215 NT1 8
  • 42215 ST1 1
  • 42215 ST1 2
  • 42215 ST1 3
  • 42215 ST1 4
  • 42215 ST1 5
  • 42215 ST1 6
  • 42215 ST1 7
  • 42215 ST1 8

NOTE: Samples NT1 1 and NT1 2 only had 700μL of RNAzol RT in them. Added additional 300μL of RNAzol RT to each.

NOTE: 0.1% DEPC-H2O used throughout this procedure was prepared on 7/15/2010 by me.

According to Jake’s notebook entry, the samples should have been previously homogenized in RNAzol RT. However, none of the samples showed evidence of being homogenized:

 

In theory, if these samples were snap frozen on liquid nitrogen after being placed in the RNAzol RT, there should be almost no impact on the RNA.

 

Procedure:

Samples were homogenized with disposable pestle in their respective tubes and vortexed.

Added 400μL of 0.1% DEPC-H2O to each sample and vortexed 15s.

Incubated samples 15mins at RT.

Centrifuged tubes 15mins at RT @ 16,000g.

750μL of the supe was transferred to a clean tube, added equal volume of isopropanol (750μL), mix by inversion (20 times), and incubated at RT for 15mins.

Centrifuged 12,000g for 10mins.

Discarded supe.

Washed pellets with 500μL of 75% EtOH (made with 0.1% DEPC-H2O) and centrifuged 4,000g for 3mins at RT. Repeated one time.

Removed EtOH and resuspended in  100μL of 0.1% DEPC-H2O. Most samples required vortexing to dissolve pellet.

Sample tubes were transferred to ice, quantified on the Roberts Lab NanoDrop1000, and stored @ -80C in their original box, pictured:

 

Results:

 

Google Spreadsheet with absorbance data: 20150506_Jake_Oly_1h_HS_RNA_ODs

Overall, the samples have excellent yields. The exceptions being the two samples that had less than 1mL of RNAzol RT in them to start (their yields are actually fine, but relative to all the other samples, they aren’t great). Should I have left them that way instead of adding additional RNAzol RT? Was there something wrong with these samples in the first place and that’s why they didn’t have a full 1mL of RNAzol RT in the tube already?

The 260/280 ratios are pretty good for most of the samples (>1.8), however I’d prefer to see RNA with 260/280 ratios >1.9.

The 260/230 ratios are amazing! The best I’ve seen coming straight out of an RNA isolation in a long time.

Eventually (once I’ve isolated RNA from the control set that corresponds to these heat shock samples), I’ll check for gDNA carryover and then, probably, DNase the RNA.

RNA Isolation – Geoduck Gonad in Paraffin Histology Blocks

UPDATE 20150528: The RNA isolated in this notebook entry may have been consolidated on 20150528.

Last week’s RNA isolation (a second attempt at obtaining RNA from the samples) performed poorly. I will re-isolate RNA from the following samples:

  • 02
  • 03
  • 04
  • 07
  • 08
  • 09
  • 35
  • 38
  • 46
  • 65
  • 67
  • 68

Instead of full sections from each histology cassette, I gouged/shaved off samples directly from the tissue in each of the blocks to maximize the amount of tissue input. However, due to the small size and susceptibility to flying around because of static electricity, none of these were able to be weighed prior to processing.

IMPORTANT:

Samples were then processed with the PAXgene Tissue RNA Kit in a single group.

Isolated RNA according to the PAXgene Tissue RNA Kit protocol with the following alterations:

  • “Max speed” spins were performed at 19,000g.
  • Tissue disruption was performed with the Disruptor Genie @ 45C for 15mins.
  • Shaking incubation step was performed with Disruptor Genie
  • Samples were eluted with 40μL of Buffer TR4, incubated @ 65C for 5mins, immediately placed on ice and quantified on the Roberts Lab NanoDrop1000.

Results:

 

 

 

Well, despite the low numbers, all of the samples (excluding 46 – 68) are double the yield of what I saw previously. This is good, but the amount of RNA from these is probably borderline sufficient quantity for RNA-Seq.

The kit has enough columns for six sample preps. I think I’ll attempt this strategy again (gouging/shaving directly from tissue in histo cassette), but really take a fair amount of tissue this time and see if I can get more.

All samples were stored @ -80C in Shellfish RNA Box #5.

RNA Isolation – Geoduck Gonad in Paraffin Histology Blocks

UPDATE 20150528: The RNA isolated in this notebook entry may have been consolidated on 20150528.

Isolated RNA from geoduck gonad previously preserved with the PAXgene Tissue Fixative and Stabilizer and then embedded in paraffin blocks. See Grace’s notebook for full details on samples and preservation.

RNA was isolated from the following samples using the PAXgene Tissue RNA Kit (Qiagen) from the following geoduck sample blocks:

  • 02
  • 03
  • 04
  • 07
  • 08
  • 09
  • 35
  • 38
  • 41
  • 46
  • 51
  • 65
  • 67
  • 68
  • 69
  • 70

IMPORTANT:

Five 5μm sections were taken from each block. A new blade was used for each block.

Samples were then processed with the PAXgene Tissue RNA Kit in two groups of eight.

Isolated RNA according to the PAXgene Tissue RNA Kit protocol with the following alterations:

  • “Max speed” spins were performed at 19,000g.
  • Tissue disruption was performed with the Disruptor Genie @ 45C for 15mins.
  • Shaking incubation step was performed with Disruptor Genie
  • Samples were eluted with 40μL of Buffer TR4, incubated @ 65C for 5mins, immediately placed on ice and quantified on the Roberts Lab NanoDrop1000.

Results:

 

 

Well, these results are certainly not good.

The first set of eight samples I processed yielded no RNA (except #38, which is only marginally better than nothing). All the samples (excluding #38) have been discarded.

The second set of eight samples I processed range from amazing to poor (#68 was barely worth keeping).

I’ll review the protocol, but at the moment I’m at a loss to explain why the first set of eight samples came up empty. Will perform another on these blocks on Monday. Grrrrr.

Samples were stored at -80C in Shellfish RNA Box #5.

RNA Isolation – Geoduck Gonad in Paraffin Histology Blocks

Isolated RNA from geoduck gonad previously preserved with the PAXgene Tissue Fixative and Stabilizer and then embedded in paraffin blocks. See Grace’s notebook for full details on samples and preservation.

 

RNA was isolated from only two samples using the PAXgene Tissue RNA Kit (Qiagen) from the following geoduck sample blocks to test out the kit:

  • 34
  • 42

IMPORTANT:

  • Prior to beginning, I prepared Buffer TR1 by adding 10μL of β-mercaptoethanol (β-ME) to 1000μL of Buffer TR1). This will be good for up to six weeks at RT.
  • Reconstituted DNase I with 550μL of RNase-free H2O. Aliquoted in 100μL volumes and stored @ -20C in the “-20C Kit Components” box.

Five 5μm sections were taken from each block.

Isolated RNA according to the PAXgene Tissue RNA Kit protocol with the following alterations:

  • “Max speed” spins were performed at 19,000g.
  • Tissue disruption was performed with the Disruptor Genie @ 45C for 15mins.
  • Shaking incubation step was performed with Disruptor Genie
  • Samples were eluted with 34μL of Buffer TR4, incubated @ 65C for 5mins, immediately placed on ice and quantified on the Roberts Lab NanoDrop1000.

Samples were stored at -80C in Shellfish RNA Box #5.

NOTE: The spreadsheet linked indicates other samples exist in the slots that I placed these two samples. Will need to update the spreadsheet to be accurate.

Results:

 

 

Looks like the kit worked! Yields are pretty good (~800ng) from each. The 260/280 ratios are great for both samples. Oddly, the 260/230 ratios for the two samples are pretty much polar opposites of each other; not sure why.

Will proceed with the remainder of the samples that were selected by Steven and Brent. Or, maybe I should try to make some cDNA from these RNA samples to verify the integrity of the RNA…

BS-seq Library Prep – C.gigas Larvae OA 1000ppm

Bisulfite Conversion

Pooled 200ng each of the sheared 1B1 (4μL) & 1B2 (used the entire sample, 20μL) 5.13.11 1000ppm C.gigas larvae DNA samples for a total of 400ng. Total volume = 24μL.

Quantified the pooled DNA using the NanoDrop1000 (ThermoFisher) prior to initiating bisulfite conversion.

Clearly, the NanoDrop measurements differ from the expected concentration. NanoDrop suggests the total amount of input DNA is ~1400ng (58ng/μL x 24μL = 1392ng). This is most likely due to RNA carryover, as DNA quantification using a fluorescence-based, double-stranded DNA assay performed previously shows a drastically lower concentration.

Proceeded with bisulfite conversion using the Methylamp DNA Modification Kit (Epigentek) in 1.5mL tube, according to the manufacturer’s protocol:

  • Added 1μL to sample, incubated 10mins @ 37C in water bath
  • Made fresh R1/R2/R3 solution (1.1mL R3 buffer added to vial of R2, vortexed 2mins, 40μL R1 added to mixture – Remainder stored @ -20C in “-20C Kit Components Box”)
  • Added 125μL of R1/R2/R3 solution to sample, incubated 90mins @ 65C in heating block with water
  • Addd 300μL R4 to sample, mixed, transferred to column, spun 12,000RPM 30s
  • Added 200μL R5 to column, spun 12,000RPM 30s
  • Added 50μL R1/ethanol solution to column, incubated 8mins @ RT, spun 12,000RPM 30s
  • Washed column with 200μL of 90% EtOH, spun 12,000RPM 30s; repeated one time.
  • Eluted DNA with 12μL R6, spun 12,000RPM 30s

Quantified post-bisulfite-treated sample on NanoDrop1000:

Definitely a low yield (~108ng) relative to the input (~400ng). Will proceed with Illumina library prep.

 

Library Prep

Illumina library prep was performed with EpiNext Post-Bisulfite DNA Library Preparation Kit (Illumina) (Epigentek).  Changes to the manufacturer’s protocol:

  • Samples were transferred to 1.5mL snap cap tubes for all magnetic bead steps in order to fit in our tube magnets.
  • PCR cycles: 15

No other changes were made to the manufacturer’s protocol.

Epigentek Barcode Indices assigned, per their recommendations for using two libraries for multiplexing (this will be combined with the 400ppm library):

Barcode #12 – CTTGTA

The library was stored @ -20C and will be checked via Bioanalyzer on Monday.

DNA Quantification – C.gigas Larvae 1000ppm

After the discovery that there wasn’t any DNA in the BS-seq Illumina library prep and no DNA in the bisulfite-treated DNA pool, I decided to try to recover any residual DNA left in the 1B2 sample. Sample 1B2 (sheared on 20150109) was dry, so I added 20μL of Buffer EB (Qiagen) to the tube. I vortexed both the 1B1 and 1B2 samples and quantified on the NanoDrop1000 (ThermoFisher). I also re-quantified the pooled BS-treated sample that had been used as input DNA for the libraries.

Results:

Spreadsheet: 20150226_Claire_sheared_Emma_1000ppm_OD260s

Sample 1B1 has ample DNA in it. Since these samples are pools of larvae, we may be able to just proceed with this sample and not worry about pooling with the biological replicate 1B2.

Sample 1B2 has a low amount of DNA, but it’s a usable quantity (total 400ng).

Pooled samples has nothing.

Will make a new pool of DNA from both 1B1 and 1B2 and attempt to make a new bisulfite-treated library.

DNA Quantification – Claire’s Sheared C.gigas Mantle Heat Shock Samples

I previously checked Claire’s sheared DNA on the Bioanalyzer to verify the fragment size and to quantify the samples. Looking at her notebook, her numbers differ greatly from the Bioanalyzer, possibly due to the fact that the DNA1000 assay chip used only measures DNA fragments up to 1000bp in size. If her shearing was incomplete, then there would be DNA fragments larger than 1000bp that wouldn’t have been measured by the Bioanalyzer. So, I decided to quantify the samples on the NanoDrop1000 (ThermoFisher) again.

 

Results:

Spreadsheet: 20150226_Claire_sheared_Emma_1000ppm_OD260s

 

 

 

Comparison of NanoDrop1000 and Bioanalyzer measurements.

Sample NanoDrop (ng/μL) Bioanalyzer (ng/μL)
2M sheared 48.03 16.28
4M sheared 190.96 58.52
6M sheared 141.56 42.98
2MHS sheared 221.93 32.45
4MHS sheared 257.48 43.82
6MHS sheared 202.02 51.12

The NanoDrop is known to overestimate sample quantities due to the indiscriminate nature of UV spectrophotometry and that could be the reason for the large discrepancy between the two measurements (i.e. RNA carryover may lead to overestimation). As such, I’ll quantify the samples using a fluorescence-based assay for double stranded DNA tomorrow in hopes of getting the most accurate measurement.

RNA Isolation – Colleens’ Sea Star Coelomycetes Samples

Isolated RNA from the following samples stored in RNAlater:

  • TH52 3.28.14 c-fluid
  • TH54 3.28.14 c-fluid
  • CH55 3.28.14 c-fluid
  • CH56 3.28.14 c-fluid
  • CH57 3.28.14 c-fluid
  • TH65 3.28.14 c-fluid
  • TH66 3.28.14 c-fluid
  • TH67 3.28.14 c-fluid

Spun samples 5000g, 20mins @ RT to pellet any cells. Discarded supe. Resuspended cells/debris in 1mL TriReagent. Disrupted cells by pipetting and vortexting. RNA was isolated using the Direct-zol RNA Miniprep Kit (ZymoResearch). RNA was DNase treated on-column, as described in the manufacturer’s protocol, using DNase I. RNA was eluted from the columns using 25uL of nuclease-free H2O and spec’d on a NanoDrop1000.

Results:

So, this is disheartening. Overall, the RNA looks pretty crappy; poor 260/280 ratios and a general shift in absorbance to 270nm. Plus, the yields aren’t that great. Maybe RNA left on the column and/or some sort of contaminant pushing these readings out of whack?

I will perform another elution on the columns with 50uL of nuclease-free H2O and spec that elution set:

There’s still a shift in the peak absorbance in most samples to 270nm… I’m going to combine the two sets of elutions and spec:

Although the 260/280 values are significantly better, there’s still this persistent shift of peak absorbance to 270nm. I contacted technical support for the kit and they say the absorbance shift is indicative of phenol contamination. They have advised that I add a volume of TriReagent to the RNA and re-run it through a new set of columns, following the entire RNA isolation protocol.