Tag Archives: total RNA

Bioanalyzer Total, mRNA and post-fragmentation SOLiD Libraries – Abalone pools

0.5uL of fragmented mRNA from each library (combined with 0.5uL) was run on Agilent Bioanalyzer 2100 using RNA Pico chips/reagents according to Agilent’s protocol.

Results:

Total RNA shows a single, distinct rRNA band, along with some low-molecular weight RNA (i.e. degraded) in both total RNA samples. mRNA samples exhibit the expected “smear” that spans a large range of molecular weights. Both mRNA samples also show residual rRNA bands, but their concentrations should be extremely low. Fragmented samples show the expected strong band of low-molecular weight RNA. The CE frag sample exhibits some larger banding, which is probably background signal (compare to the empty lane labelled “Sample 7″).

Will proceed with rest of library procedure for both fragmented samples.

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RNA Precipitation & mRNA Isolation for SOLiD Libraries – Pooled abalone total RNA: Carmel control, Carmel exposed

RNA of 8 samples from each group was pooled equally from each individual. RNA was precipitated according to Ambion’s MicroPolyA Purist Kit. Used 0.1 volumes of 3M NaAOc, pH=5.2, 2.5vols of 100% EtOH and incubated 30min @ -80C. Pelleted RNA 16,000g, 30mins. Washed pellet w/70% EtOH and pelleted RNA 16,000g, 15mins. Pellets were resuspended in 50uL nuclease-free H2O and spec’d:

Total RNA pools look really nice. ~45ug of total RNA in each sample.

Isolated mRNA from each pool using Ambion’s MicroPolyA Purist Kit according to protocol. Samples were processed 2x as recommended by Ambion’s SOLiD Whole Transcriptome Analysis Kit. Final elution was 200uL of The RNA Storage Solution. Samples were spec’d:

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Bioanalyzer for SOLiD libraries – Total and mRNA from Perch, Lake Trout & Herring RNA samples (CONTINUED from yesterday)

Total and mRNA aliquots (~5ng/uL) were run on the Agilent Bioanalyzer Pico RNA chips.

Results:

The gel below shows the comparison/results of total RNA and subsequent mRNA isolations. The gel indicates the following:

  1. The HPWS09 total RNA (Herring) is totally degraded, but shows the expected profile in the mRNA prep. It would be extremely interesting to see if the degradation has any effect on sequencing, as the mRNA will get fragmented any way in the next step of library construction.

  2. mRNA isolations worked for all samples. Although one might be inclined to say that mRNA isolation did NOT work for the WB sample, one has to take in to consideration that the gel software adjusts the gel contrast to enhance low signals. That’s why all the mRNA samples exhibit a dark background. mRNA generates a broad, relatively weak signal when compared to a total RNA sample. So, the software attempts to boost the low signal for display purposes. Thus, if we were to decrease this signal boosting (or contrast) for the WB mRNA so that the background color matched the WB total RNA background color (white), the rRNA bands visible in the WB mRNA sample would fade to a point where they would not be visible. See the electropherogram overlay (below the gel) for a more visual comparison of this concept.

Electropherogram Overlays of WB total RNA and WB rRNA

The WB total RNA is the red graph which shows extremely high levels of rRNA (as expected). After subsequent mRNA isolation (the blue graph), the rRNA is virtually gone and no longer comprises a significant portion of the sample.

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mRNA Isolation for SOLiD – Perch, Lake Trout, and Herring total RNA

Received pooled lean and siscowet RNA from Rick. Samples will be processed immediately for SOLiD fragment libraries. Two 1.5mL snap cap tubes labelled:

L.T. 2ug muscle sisco pool

L.T. 2ug muscle lean pool

RNA was first precipitated according to the Ambion MicroPolyA Purist Kit protocol (0.1 vol 5M ammonium acetate, 1uL glycogen, 2.5 vols 100% EtOH). Samples were incubated @ -80C for 30mins. Samples were resusupended in 250uL nuclease-free H2O and spec’d.

 

Starting quantities PRIOR to total RNA precipitation:

Perch Samples:

WB tRNA (WB tRNA ~12ug 24.5uL)

PQ tRNA (PW tRNA ~12ug 21.88uL)

CT tRNA (CT tRNA ~12ug 25uL)

Herring:

1 G/O HPWS09 (20ug)

Lake Trout:

L.T. 20ug muscle sisco pool

L.T. 20ug muscle lean pool

Removed 1uL of each sample, diluted to ~5ng/uL and stored @ -80C to run on the Bioanalyzer.

Used Ambion MicroPolyA Purist Kit according to protocol. Samples were treated twice to ensure elimination of rRNA from the samples. After second run through MicroPolyA Purist, samples were EtOH precipitated O/N @ -20C according to Ambion’s MicroPolyA Purist protocol.

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RNA Fragmentation – Herring Liver mRNA for SOLiD Libraries

Samples from 20091203. 0.5uL was removed from each and transferred to separate tubes and diluted to < 5ng/uL for subsequent Bioanalyzer analysis using the Pico chip. Samples were fragmented using RNase III according to the Ambion WTK protocol and then cleaned up/concentrated using the Invitrogen RiboMinus Concentration Module according to the Ambion WTK protocol.

Samples were spec’d prior to running on the Bioanalyzer:

Concentrations/absorbance values are not accurate when using the NanaDrop after using the RiboMinus Concentration module, according to the Ambion WTK protocol. However, yields seem pretty good…

Total, mRNA and fragmented mRNA from each of the four samples was run on the Pico chip with the Eukaryote Total RNA Bioanalyzer protocol.

Results:

The 2L tot (total RNA) and 3L tot (total RNA) samples are clearly very good quality. 2L tot does exhibit some very slight degradation, though. 4L tot (total RNA) and 6L tot (total RNA) show a much greater degree of degradation. All mRNA samples show complete removal of any trace, contaminating rRNA. The fragmented samples (the last four samples on the gel image above) all appear to be perfect. The 4L frag sample simply has less RNA loaded and that is why it is not as dark as the other three fragmented samples. Despite the degradation in the 4L tot and 6L tot samples, the fragmentation profile looks good and we will proceed with making the cDNA libraries for those samples.

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RNA Isolation – Sepia samples

Isolated RNA from 7 sepia samples received 20091125. Samples were removed from RNA Later, blotted and homogenized in 500uL of TriReagent. 500uL of additional TriReagent was added to the tubes after homogenization. Procedure was followed normally. The sepia retina RNA was isolated separately from the other samples and was resuspended in 100uL of 0.1% DEPC-H2O. The remaining samples were isolated and resuspended in 20uL of 0.1% DEPC-H2O. Nearly all samples had some sort of purple tint to them, ranging from almost black to extremely faint purple hue. The samples were spec’d and then stored @ -80C in Sam’s RNA Box #1.

Results:

Nearly all of the samples exhibited very strange curves and mediocre 260/280 ratios (for RNA). Could be due to the “purple stuff” carryover or possibly an effect of the RNA Later from which the samples were stored.

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RNA Gel – V. tubiashii mRNA samples (from 20081224)

external image 20081229.png

Lane 1 – Empty
Lane 2 – Total RNA, Control
Lane 3 – mRNA, Control
Lane 4 – Total RNA, Vibrio+gigas
Lane 5 – mRNA, Vibrio+gigas

Results:

rRNA removal seems to have worked relatively well. Still some residual rRNA present in the mRNA samples. Will submit 200ng of the Vibrio+gigas mRNA to HTGU for Illumina sequencing.

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rRNA Removal – V. tubiashii total RNA from yesterday

rRNA removal was continued from O/N precipitation. Processed the samples according to the Ambion MICROBExpress Kit protocol and resuspended final pellets in 25uL of The RNA Storage Solution. Samples were spec’d on the NanoDrop.

external image 20081224%20RNA%20SJW.PNG

Samples were stored @ -80C in Sam’s RNA Box #1.

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