Tag Archives: paraffin

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.
  • 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.

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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.
  • 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.

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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 failed for more than half of the samples I processed. I will re-isolate RNA from the following samples:

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

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 six.

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.
  • 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 very consistent with the data from the last isolation performed on these samples. This fact suggests that the problem lies with the tissue samples and not the isolation (since the isolation has been performed two separate times on these same samples and the results have come out virtually identical both times).

All samples with concentrations < 5ng/μL were discarded. The remaining samples were stored @ -80C in Shellfish RNA Box #5:

  • 35
  • 38
  • 65
  • 67

Will discuss with Steven, look at Grace’s notebook to review the preservation process for these samples, and review the PAXgene Tissue RNA Kit to see if it will accommodate a greater number of microtome sections to use for isolation.

 

 

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Bioanalyzer Submission – Geoduck Gonad RNA from Histology Blocks

Submitted 3μL (~75ng) of RNA from each of the two gonad samples isolated from foot tissue embedded in paraffin histology blocks 20150408 (to assess quality of RNA) to Jesse Tsai at University of Washington Department of Environmental and Occupational Health Science Functional Genomics Laboratory:

  • Geoduck Block 34
  • Geoduck Block 42

Jesse will determine if the samples should be run on the RNA Pico or the RNA Nano chips.

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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.
  • 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…

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