Tag Archives: RLOv_head_to_tail

qPCR – pCR2.1/RLOv Standard Curves Testing

Earlier today, I created dilution series of the following two linearized plasmids to develop qPCR assays:

  • pCR2.1/RLOv_DNA_helicase
  • pCR2.1/RLOv_head_to_tail

Master mix calcs: 20151106 – qPCR RLOv Standard Curves

All samples were run in triplicate on a CFX96 thermal cycler (BioRad).

Cycling params, plate layout, etc. can be found in the qPCR Report (see Results below).

qPCR Data File (CFX96): Sam_2015-11-06 18-17-41_CC009827.pcrd
qPCR Report (PDF): Sam_2015-11-06 18-17-41_CC009827.pdf

DNA Helicase Curve

Amplifcation plots and the standard curve best fit line looks really good. Efficiency is very close to 100% and the R^2 = 0.99. Additionally, virtually all of the replicates are very tight. This looks like it will be totally usable as a standard curve for developing a qPCR assay that targets the RLOv DNA helicase gene.


Head-to-tail Curve

This curve is way wonky. Interestingly, the end-point fluroescence levels for this curve 5-fold lower than the DNA helicase curve. I’ll likely repeat this qPCR to see if these crappy results are repeatable. However, having a single qPCR assay (the DNA helicase standard curve) for RLOv detection/quantification might be sufficient, rendering a second qPCR assay unneeded.


PCR – RLOv Clones

Colony PCRs were performed on each of the transformations from 20151015 (RLOv_ DNA_helicase, RLOv_head_to_tail, RLOv_membrane_gene_1, RLOv_membrane_gene_2, RLOv_tail_to_fiber) to confirm successful ligations in plasmid pCR2.1 using the M13F/R vector primers.

Colonies were picked form the transformation plates with pipette tips, re-streaked on a secondary, gridded, numbered LBAmp100+x-gal plate and then used to inoculate the respective PCR reactions.

Six white colonies (positive clones) and a single blue colony (negative clone) were selected from each transformation.

Master mix calcs are here (Google Sheet): 20151019 – Colony PCRs RLOv

Restreaked plates were incubated @ 37C O/N and then stored @ 4C (Parafilmed).

30μL of each reaction was run on a 1% agarose 1x Low TAE gel, stained w/EtBr.



All the PCRs look good. All white colonies selected contain a PCR product of appropriate size (i.e. larger than the blue colonies; negative [-C] control). Will select clones #1 from each to grow up for plasmid prep.


Cloning – Purified Abalone RLOv PCR Products

Purified PCR products from 20151008 (in situ hybridization [ISH] primers) & 20151009 (qPCR primers) RLOv primers were used for cloning. The qPCR primers are intended to develop a qPCR standard curve and the ISH primers are intended to develop three ISH probes.

  • RLOv_DNA_helicase (for qPCR)
  • RLOv_head_to_tail_gene (for qPCR)
  • RLOv_membrane_gene_1 (for ISH)
  • RLOv_membrane_gene_2 (for ISH)
  • RLOv_tail_fiber_gene (for ISH)

The PCR products were separately ligated using The Original TA Cloning Kit (Invitrogen).


Purified PCR 5 NA
10x Ligase Buffer 1 5.5
pCR2.1 Vector 2 5.5
H2O 1 5.5
T4 DNA Ligase 1 5.5
TOTAL 10 22

Ligation reactions were set up on ice.Combined 5μL of purified PCR product with 5μL of ligation master mix in a 1.5mL snap cap tube. Incubated 24hrs @ RT.



50μL of X-gal (20mg/mL) was added to a LB-Amp100 plates, spread and warmed @ 37C.

Five vials of OneShot TOP 10 chemically competent cells (Invitrogen) were thawed on ice. 3μL of the ligation reaction was added to the cells, gently mixed and incubated on ice for 5mins. 50μL of cells were transferred to the LB-Amp100+X-gal plates, spread and incubated O/N at 37C.


PCR – RLOv for Cloning & Sequencing

After yesterday’s confirmation that the qPCR primer/probe sets for RLOv DNA helicase and head-to-tail were functional and specific for the RLOv, I needed to generate PCR products to clone and sequence.

Primers tested:

  • RLOv_DNA_helicase
  • RLOv_head_to_tail_gene

Template DNA:

  • 06:6-54

All samples were run in duplicate.

Master mix calcs are here: 20151009 – PCR RLOv

Cycling Params (PTC-200; MJ Research)

Initial Denaturation
  • 95
  • 600
40 Cycles
  • 95
  • 55
  • 72
  • 15
  • 15
  • 30

Samples were run on a 0.8% agarose 1x TBE gel, stained with ethidium bromide.


Amplification looks great. No amplification in no template controls (NTCs). Excised bands and purified products using Ultrafree DA Spin Columns (Millipore). Samples will be stored @ 4C until I am able to clone them for sequencing.


Gel image showing excised bands. And, it’s a complete hack job, which is embarrassing…


qPCR – RLOv Specificity Check

After yesterday’s confirmation that the primer/probe sets for RLOv DNA helicase and head-to-tail were functional and specific for the RLOv (and don’t amplify RLO alone), I needed to confirm that the qPCRs only generated a single product in each reaction via melt curve analysis.

Primers tested:

  • RLOv_DNA_helicase
  • RLOv_head_to_tail_gene

Template DNA:

  • 06:6-54

NOTE: Remaining volume of template DNA wasn’t going to be sufficient for all reactions, so added 100μL of NanoPure H2O. Seeing how early the amplification was in yesterday’s qPCR (Cq ~15), this dilution should be fine.

All samples were run in duplicate.

Master mix calcs are here: 20151009 – qPCR RLOv

Plate layout, cycling params, etc can be found in the qPCR Report (see Results).

qPCR Report (PDF): Sam_2015-10-09 12-36-54_CC009827.pdf
qPCR Data File (CFX96): Sam_2015-10-09 12-36-54_CC009827.pcrd

Both primer sets amplified a single PCR product. This is demonstrated by the single melt peak for each primer set.


qPCR – New Withering Syndrome Phage Primers

Ran qPCR with the newly designed primers and probes for the following targets:

  • DNA Helicase (RLOv)
  • Head-to-tail gene (RLOv)
  • WSN1 (RLO)

Template DNA used:

In the histology scoring pictures below, the “New” column refers to histology scores for the presence of the phage. A score = 0 means no phage.

  • 06:5-6 (RLO only)

  • 06:6-54 (RLOv)

  • UW08:22-11A (naive pinto abalone; no RLO)


Master mix calcs are here: 20151008 – qPCR WS phage

All samples were run in duplicate. Cycling params, plate layout, etc. can be seen in the qPCR Report (see below).


qPCR Report (PDF): Sam_2015-10-08 17-45-38_CC009827.pdf
qPCR Data File (CFX96): Sam_2015-10-08 17-45-38_CC009827.pcrd

ORANGE – WSN1; BLUE – DNA Helicase; GREEN – Head-to-tail

The results look great! The two RLOv (phage) primer sets only amplify in the sample that has histological confirmation of the presence of phage (06:6-54). They do not amplify in the RLO-only (no phage; 06:5-6) sample, demonstrating that these two primer sets are indeed specific to the phage and don’t  amplify the RLO.

The withering syndrome primers (WSN1) were run to confirm that there aredetectable levels of RLO in both the RLOv & RLO samples, to further support the evidence showing the specificity of the two phage primer sets.

Will use the two RLOv primer sets in a conventional PCR for cloning/sequencing and development and validation of a qPCR standard curve.