Tag Archives: ctenidia

DNA Isolation – Geoduck Ctenidia gDNA

Isolated additional gDNA for the genome sequencing. In an attempt to obtain better yields, I used ctenidia (instead of adductor muscle). Additionally, to try to improve the quality (260/280 & 260/230 ratios) of the gDNA, I added a chloroform step after the initial tissue homogenization.

Used 190mg of Panopea generosa ctenidia collected by Brent & Steven on 20150811.

  • Homogenized in 500μL of DNAzol.
  • Added additional 500μL of DNAzol.
  • Centrifuged 12,000g, 10mins, @ RT.
  • Split supernatant equally into two tubes.
  • Added 500μL of chloroform and mixed moderately fast by hand.
  • Centrifuged 12,000g, 10mins, RT.
  • Combined aqueous phases from both tubes in a clean tube.
  • Added 500μL of 100% EtOH and mixed by inversion.
  • Spooled precipitated gDNA and transferred to clean tube.
  • Performed 3 washes w/70% EtOH.
  • Dried pellet 3mins.
  • Resuspended in 200μL of Buffer EB (Qiagen).
  • Centrifuged 10,000g, 5mins, RT to pellet insoluble material.
  • Transferred supe to clean tube.

DNA was quantified using two methods: NanoDrop1000 & Qubit 3.0 (ThermoFisher).

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

Results:

Qubit Data (Google Sheet): 20151125_qubit_gDNA_geoduck_oly_quants

METHOD CONCENTRATION (ng/μL) TOTAL (μg)
Qubit 105 21.0
NanoDrop1000 173 34.6

 

Yield is definitely much, much better than adductor muscle! Should’ve switched to a different tissue a long time ago! We should finally have sufficient quantities of gDNA to allow for BGI to proceed with the rest of the genome sequencing! Will run sample on gel to evaluate integrity and then send off to BGI.

The NanoDrop & Qubit numbers still aren’t close (as expected).

The addition of the chloroform step definitely helped improve the 260/280 OD ratio (see below). However, the addition of that step had no noticeable impact on the 260/230 OD ratios, which is a bit disappointing.

 

NanoDrop Absorbance Values & Plots

 

Share

Oyster Sampling – Oly Fidalgo 2SN, 2HL, 2NF Reciprocal Transplants Final Samplings

The remaining Olympia oysters from Jake Heare’s reciprocal transplant experiment have been retrieved from field sites and are awaiting sampling. The oysters have been stored in the cold room (temp?) for 15 days so far.

The previous sampling scheme was described here: DNA Isolations – Fidalgo 2SN Reciprocal Transplants Final Samplings

Sampling scheme for today was as follows:

  1. Assign unique number to oysters (1-100 for each of the three populations)
  2. Photograph with ruler for future shell measurements
  3. Weigh oysters
  4. Dissect ctenidia for DNA isolation in 350μL MBL1 Buffer + 25μL Proteinase K (reagents part of the E.Z.N.A. Mollusc Kit [Omega BioTek)
  5. Preserve portion of remaining body tissue (not viscera; gonad/digestive gland) in 1mL RNAlater (Life Technologies)

Ctenidia samples were stored -80C in the buffer/pro k solution for DNA isolation at a later date.

RNAlater samples will be stored over the weekend at 4C and then transferred to -20C for long term storage.

All oyster data is here (Google Sheet): Oly reciprocal final sampling

All photos from today’s sampling are here: Oyster Measurement Photos

Share

DNA Isolations – Fidalgo 2SN Reciprocal Transplants Final Samplings

The remaining Olympia oysters from Jake Heare’s reciprocal transplant experiment have been retrieved from field sites and are awaiting sampling. The oysters have been stored in the cold room (temp?) for 6 days so far.

Sampling scheme is as follows:

  1. Assign unique number to oysters
  2. Photograph with ruler for future shell measurements
  3. Weigh oysters
  4. Dissect ctenidia for DNA isolation
  5. Dissect & discard viscera (e.g. digestive gland and gonad)
  6. Weigh remaining body
  7. Preserve remaining body in RNAlater
  8. Weigh empty shells


Mrunmayee photographed & initiated dissections of oysters #3 – 8
. I took over for oyster #9 -14.

All oyster data is here (Google Sheet): Oly reciprocal final sampling

DNA was isolated using the E.Z.N.A. Mollusc Kit (Omega Biotek) according to the manufacturer’s protocol with the following changes:

  • No optional steps were performed
  • Ctenidia tissue was lysed for 3hrs @ 60C
  • Single elution of 50μL

Samples were stored @ -20C in: Oly gDNA Oly Reciprocal Transplant Final Sampling Box #1.

Share

Reverse Transcription – O.lurida DNased RNA 1hr post-mechanical stress

Performed reverse transcription on the Olympia oyster DNased RNA from the 1hr post-mechanical stress samples from Jake’s project. To accommodate the large numbers of anticipated genes to be targeted in subsequent qPCRs, I prepared 100μL reactions (normally, 25μL reactions are prepared) using 250ng of each DNased RNA. A 1:10 dilution of the oligo dT primers (Promega) was prepared to improve pipetting accuracy. All incubations were performed in a thermal cycler without using a heated lid.

DNased RNA was combined with NanoPure H2O and oligo dT primers in 24 wells of a PCR plate, heated @ 70C for 10mins and immediately placed on ice. After 5mins, the plate was spun 2000g @ RT for 2mins and returned to ice.

25.25μL of a master mix containing 5x M-MLV Buffer (Promega), dNTPs (10mM each; Promega), and M-MLV Reverse Transcriptase (50U/rxn; Promega) was distributed to each well and mixed via pipetting. The plate was heated @ 42C for 1hr, 95C for 3mins. The plate was spun 2000g @ RT for 2mins and then stored @ -20C.

Plate layout and all calculations can be found here (Google Sheet): 20150806_Jake_oly_mech_stress_cDNA_calcs

Share

qPCR – Jake’s O.lurida ctenidia 1hr post-mechanical stress DNased RNA

Ran qPCR on DNased RNA from earlier today to assess whether there was any residual gDNA after the DNase treatment with Oly_Actin_F/R primers (SR IDs: 1505, 1504).

Used 1μL from all templates.

All samples were run in duplicate.

Positive control was HL1 O.lurida DNA isolated by Jake on 20150323.

Cycling params:

  • 95C – 2.5mins
  • 40 cycles of:
    • 95C – 10s
    • 60C – 20s
  • Melt curve

Master mix calcs are here: 201500806_qPCR_Oly_DNased_RNA

qPCR Plate Layout: 20150806_qPCR_plate_Jake_Oly_DNased_RNA

Results:

qPCR Data File (Opticon): 20150806_165044.tad
qPCR Report (Google Spreadsheet): 20150806_qPCR_Report_Jake_Oly_DNased_RNA

Positive control comes up around cycle ~21.

No amplification in the no template controls.

Two wells of the DNased RNA samples exhibit amplification (E3, F6), however the corresponding respective replicate does not. Will proceed with reverse transcription.

 

Amplification Plots

Positive Controls

 

Melt Curves

Positive Controls (HL1)

DNased RNA Samples

Follow the green and red lines with the vertical bars. The different colors reflect that those are two different samples. Additionally, their respective replicates do not exhibit amplification.

Share

RNA Quantification – O.lurida 1hr post-mechanical heat stress DNased RNA

DNased RNA from 07272015 was quantified using the Roberts Lab NanoDrop1000.

 

Results:

The 260/280 ratios don’t look great, but that is most likely due to the DNase treatment. The DNase that’s added to each sample isn’t actually removed, so that additional protein will skew the 260/280 ratios. Will proceed with qPCR to check for any residual gDNA in these samples.

 

Share

DNase Treatment – O.lurida Ctenidia 1hr Post-Mechanical Stress RNA

Quantified the RNA I isolated from Jake’s samples on 20150715 and 20150710 using the Roberts Lab NanoDrop1000 (ThermoFisher).

 

 

 

Overall, the yields are good. The 260/280 ratios are mediocre. Will proceed with DNase treatment.

DNased 1.5ug of RNA from each sample using the Turbo DNA-free Kit (Ambion/Life Technologies), following the “rigorous” protocol.

Briefly:

  • 50μL reactions were carried out in 0.5mL tubes
  • added 1μL of DNase to each tube
  • incubated 30mins @ 37C
  • added additional 1μL of DNased
  • incubated 30mins @ 37C
  • added 0.2 vols (10.2μL) of DNase Inactivation Reagent
  • incubated and mixed for 2mins @ RT
  • spun 1.5mins, 10,000g @ RT
  • transferred 50μL of supe to sterile 1.5mL snap cap tubes
  • spec’d on Roberts Lab NanoDrop1000

Samples were stored @ -80C in Shellfish RNA Box #6. Will quantify at a later date.

DNase reaction calcs: 20150727_Jake_Oly_mech_stress_DNase_calcs

 

Share

RNA Isolation – O.lurida Ctenidia 1hr Post-Mechanical Stress

Isolated RNA from Jake’s Ostrea lurida ctenidia samples that had been subjected to mechanical stress (from 20150422).

Despite the indication in this notebook, the samples had not been previously homogenized in RNAzol RT. I thawed the samples, homogenized them and followed the RNAzol RT protocol for total RNA isolation. Here’s the list of samples:

  • 42215 HM1 1
  • 42215 HM1 2
  • 42215 HM1 3
  • 42215 HM1 4
  • 42215 HM1 5
  • 42215 HM1 6
  • 42215 HM1 7
  • 42215 HM1 8
  • 42215 SM1 1
  • 42215 SM1 2
  • 42215 SM1 3
  • 42215 SM1 4
  • 42215 SM1 5
  • 42215 SM1 6
  • 42215 SM1 7
  • 42215 SM1 8

RNA was resuspended in 50μL of 0.1%DEPC-H2O and stored @ -80C in the original box they came from.

Share

RNA Isolation – O.lurida Ctenidia 1hr Post-Mechanical Stress

Isolated RNA from Jake’s Ostrea lurida ctenidia samples that had been subjected to mechanical stress (from 20150422).

Despite the indication in this notebook, the samples had not been previously homogenized in RNAzol RT. I thawed the samples, homogenized them and followed the RNAzol RT protocol for total RNA isolation. Here’s the list of samples:

  • 42215 NM1 1
  • 42215 NM1 2
  • 42215 NM1 3
  • 42215 NM1 4
  • 42215 NM1 5
  • 42215 NM1 6
  • 42215 NM1 7
  • 42215 NM1 8

RNA was resuspended in 50μL of 0.1%DEPC-H2O and stored @ -80C in the original box they came from.

Share

Reverse Transcription – Subset of Jake’s O.lurida DNased RNA

Currently don’t have sufficient reagents to perform reverse transcription on the entire set of DNased RNA (control and 1hr.heat-shocked O.lurida ctenidia samples). To enable Jake to start testing out some of his primers while we wait for reagents to come in, Steven suggested I generate some cDNA for him to use.

Used the following DNased RNA:

  • HC1
  • NC1
  • SC1
  • HT1 1
  • NT1 1
  • ST1 1

Reverse Transcription Calcs: 20150522_Jake_Oly_cDNA_Calcs

Briefly:

  • Reactions run in 0.5mL snap cap tubes
  • 250ng of DNased RNA used in each reaction
  • Combined DNased RNA with oligo dT primers and water; incubated 70C 5mins; immediately placed on ice
  • Added 6.75μL of buffer/dNTP/enzyme master mix to each sample; incubated 42C for 1hr; 95C for 3mins

Samples will be given to Jake and stored @ -20C.

Share