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.

Bioinformatics – Trimmomatic/FASTQC on C.gigas Larvae OA NGS Data

In another troubleshooting attempt for this problematic BS-seq Illumina data, I’m going to use Trimmomatic to remove the first 39 bases of each read. This is due to the fact that even after the previous quality trimming with Trimmomatic, the first 39 bases still showed inconsistent quality:

 

Ran Trimmomatic on just a single data set to try things out: 2212_lane2_CTTGTA_L002_R1_001.fastq.gz

Notebook Viewer: 20150506_Cgigas_larvae_OA_trimmomatic_FASTQC

Jupyter (IPython) notebook: 20150506_Cgigas_larvae_OA_trimmomatic_FASTQC.ipynb

Results:

Trimmed FASTQ: 20150506_trimmed_2212_lane2_CTTGTA_L002_R1_001.fastq.gz

FASTQC Report: 20150506_trimmed_2212_lane2_CTTGTA_L002_R1_001_fastqc.html

You can see how flat the newly trimmed data is (which is what one would expect).

Steven will take this trimmed dataset and try additional mapping with it to see if removal of the first 39 bases will improve the mapping.

 

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.

BLAST – C.gigas Larvae OA Illumina Data Against GenBank nt DB

In an attempt to figure out what’s going on with the Illumina data we recently received for these samples, I BLASTed the 400ppm data set that had previously been de-novo assembled by Steven: EmmaBS400.fa.

Jupyter (IPython) Notebook : 20150501_Cgigas_larvae_OA_BLASTn_nt.ipynb

Notebook Viewer : 20150501_Cgigas_larvae_OA_BLASTn_nt

Results:

BLASTn Output File: 20150501_nt_blastn.tab

BLAST e-vals <= 0.001: 20150501_Cgigas_larvae_OA_blastn_evals_0.001.txt

Unique BLAST Species: 20150501_Cgigas_larvae_OA_unique_blastn_evals.txt

 

Firstly, since this library was bisulfite converted, we know that matching won’t be as robust as we’d normally see.

However, the BLAST matches for this are terrible.

Only 0.65% of the BLAST matches (e-value <0.001) are to Crassostrea gigas. Yep, you read that correctly: 0.65%.

It’s nearly 40-fold less than the top species: Dictyostelium discoideum (a slime mold)

It’s 30-fold less than the next species: Danio rerio (zebra fish)

Then it’s followed up by human and mouse.

I think I will need to contact the Univ. of Oregon sequencing facility to see what their thoughts on this data is, because it’s not even remotely close to what we should be seeing, even with the bisulfite conversion…

Goals – May 2015

Here are the things I plan to tackle throughout the month of May:

Geoduck Reproductive Development Transcriptomics

My primary goal for this project is to successfully isolate RNA from the remaining, troublesome paraffin blocks that have yet to yield any usable RNA. The next approach to obtain usable quantities of RNA is to directly gouge tissue from the blocks instead of sectioning the blocks (as recommended in the PAXgene Tissue RNA Kit protocol). Hopefully this approach will eliminate excess paraffin, while increasing the amount of input tissue. Once I have RNA from the entire suite of samples, I’ll check the RNA integrity via Bioanalyzer and then we’ll decide on a facility to use for high-throughput sequencing.

 

BS-Seq Illumina Data Assembly/Mapping

Currently, there are two projects that we have performed BS-Seq with (Crassostrea gigas larvae OA (2011) bisulfite sequencing and LSU C.virginica Oil Spill MBD BS Sequencing) and we’re struggling to align sequences to the C.gigas genome. Granted, the LSU samples are C.virginica, but the C.gigas larvae libraries are not aligning to the C.gigas genome via standard BLASTn or using a dedicated bisulfite mapper (e.g. BS-Map). I’m currently BLASTing a de-novo assembly of the C.gigas larvae OA 400ppm sequencing that Steven made against the NCBI nt DB in an attempt to assess the taxonomic distribution of the sequences we received back. I’ll also try using a different bisulfite mapper, bismark, that Mackenzie Gavery has previously used and has had better results with than BS-Map.

 

C.gigas Heat Stress MeDIP/BS-Seq

As part of Claire’s project, there’s still some BS-Seq data that would be nice to have to complement the data she generated via microarray. It would be nice to make a decision about how to proceed with the samples. However, part of our decision on how to proceed is governed by the results we get from the two projects above. Why do those two projects impact the decision(s) regarding this project? They impact this project because in the two projects above, we produced our own BS-Seq libraries. This is extremely cost effective. However, if we can’t obtain usable data from doing the library preps in-house, then that means we have to use an external service provider. Using an external company to do this is significantly more expensive. Additionally, not all companies can perform bisulfite treatment, which limits our choices (and, in turn, pricing options) on where to go for sequencing.

 

Miscellany

When I have some down time, I’ll continue working on migrating my Wikispaces notebook to this notebook. I only have one year left to go and it’d be great is all my notebook entries were here so they’d all be tagged/categorized and, thus, be more searchable. I’d also like to work on adding README files to our plethora of electronic data folders. Having these in place will greatly facilitate the ability of people to quickly and more easily figure out what these folders contain, file formats within those folders, etc. I also have a few computing tips/tricks that I’d like to add to our Github “Code” page. Oh, although this isn’t really lab related, I was asked to teach the Unix shell lesson (or, at least, part of it) at the next Software Carpentry Workshop that Ben Marwick is setting up at UW in early June. So, I’m thinking that I’ll try to incorporate some of the data handling stuff I’ve been tackling in lab in to the lesson I end up teaching. Additionally, going through the Software Carpentry materials will help reinforce some of the “fundamental” tasks that I can do with the shell (like find, cut and grep).

In the lab, I plan on sealing up our nearly overflowing “Broken Glass” box and establishing a new one. I need to autoclave, and dispose of, a couple of very full biohazard bags. I’m also going to vow that I will get Jonathan to finally obtain a successful PCR from his sea pen RNA.

BLASTN – C.gigas OA Larvae to C.gigas Ensembl 1.24 BLAST DB

In an attempt to figure out what’s going on with the Illumina data we recently received for these samples, I BLASTed the 400ppm data set that had previously been de-novo assembled by Steven: EmmaBS400.fa.

I also created a nucleotide BLAST database (DB) from the Crassostrea_gigas.GCA_000297895.1.24.fa

Jupyter (IPython) Notebook: 20150429_Gigas_larvae_OA_BLASTn.ipynb

Notebook Viewer: 20150429_Gigas_larvae_OA_BLASTn

 

Results:

The results are not great.

All query contigs successfully BLAST to sequences in the C.gigas Ensembl BLAST DB. However, only 33 of the sequences (out of ~37,000) have an e-value of 0.0. The next best e-value for any matches is 0.001. For the uninitiated, that value is not very good, especially when you’re BLASTing against the same exact species DB.

Will BLASTn the C.gigas contigs against the entire GenBank nt (all nucleotides) to see what the taxonomy breakdown looks like of these sequences.

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.
  • 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 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.

 

 

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.