Category Archives: Miscellaneous

Bioanalyzer – Tanner Crab RNA Isolated with RNeasy Plus Mini Kit

Ran the four Tanner crab RNA samples that I isolated yesterday on the Seeb Lab Bioanalyzer 2100 (Agilent) using the RNA Pico 6000 Kit.

Samples were run following kit protocol:

  • Chip priming station in Position C with syringe clip at top position

  • RNA denatured at 70C for 2mins and stored on ice.

  • RNA ladder aliquot was from 20160826 by Hollie Putnam.

RESULTS

Bioanalyzer data file (XAD):

ELECTROPHEROGRAMS:

GEL REPRESENATATIONS

These results look great to me. Clear, defined peaks/bands, representing ribosomal RNA.

Oddly, one sample (crab_506) appears to be shifted, relative to the other three, despite exhibiting the same peak/banding pattern. Not sure what would cause something like this; contaminants?

Regardless, we finally have clean RNA and have a usable Bioanalyzer profile to use for reference for crab RNA.

NOTE: The lanes marked with red on the gel representation image indicate that a ribosomal integrity number (RIN) could not be calculated. This is to be expected! The RIN is based on the expectation of two rRNA bands. The anomaly is sample crab_451 – a RIN was actually determined for that sample!

Will likely move forward with additional RNA isolations using the RNeasy Plus Kit (Qiagen).

RNA Cleanup – Tanner Crab RNA

In a continued attempt to figure out what we can do about the tanner crab RNA, Steven tasked me with using an RNeasy Kit to cleanup some existing RNA.

Here’re the samples grace provided:

All of the RNA had some sort of undissolved/insoluble material present. Here’s an example (this is the worts of the bunch – others did not have such large/dense pellets):

Samples were cleaned up using the [RNeasy Plus Mini Kit (Qiagen)]. Added 350uL of Buffer RLT Plus (no beta-mercaptoethanol added) to each sample, vortexed, and then processed according to the manufacturer’s protocol (skipped gDNA Eliminator spin column step).

Samples were eluted with 30uL of nuclease-free water.

Samples were quantified using the Roberts Lab Qubit 3.0 with the RNA High Sensitivity asssay (Invitrogen). Used 5uL of sample for measurements.

Samples were also assessed with the Roberts Lab NandoDrop1000.

Samples were recovered from the pedestal after measurement.

RNA was given to Grace for storage at -80C.

RESULTS

Qubit measurements (Google Sheet):
– 20180731_qubit_RNA_crab_cleanup

NanoDrop Table:

All concentrations were too low for detection via NanoDrop.

Qubit quantification indicate yields ranging from ~25ng to ~192.5ng.

Will share info with Grace and let her compare these numbers to her original concentrations to see if there’s any differences.

Regardless, based on my earlier RNA isolation today, these samples should now be much cleaner and we should be able to trust the Qubit quantifications.

RNA Isolation – Tanner Crab Hemolymph Using RNeasy Plus Mini Kit

Tanner crab RNA has proved a bit troublesome. As such, Steven asked me to try isolating some RNA using the RNeasy Plus Mini Kit (Qiagen) to see how things would turn out.

Grace provided me with the following samples:

Crab hemolymph had been collected (100uL?) and preserved with 1mL (?) of RNAlater. Grace pelleted the samples, removed the supernatant, and stored the pelleted material at -80C. Here’s what that looked like:

RNA was isolated according to the manufacturer’s protocol – following guideline for samples with < 1 x 106 cells.

One interesting thing that happened is a precipitate formed after adding the initial buffer to the sample:

A solid precipitate formed in each of the tubes that could not be dispersed – it actually looked like a small piece of paper was now present in each tube.

Samples were spun and the supernatant was utilized (this was the normal progression of the protocol, regardless of this precipitate forming).

Samples were eluted with 30uL of nuclease-free water.

Samples were quantified using the Roberts Lab Qubit 3.0 with the RNA High Sensitivity asssay (Invitrogen). Used 5uL of sample for measurements.

Samples were also assessed with the Roberts Lab NandoDrop1000. Samples were recovered from the pedestal after measurement.

RNA was given to Grace for storage at -80C.

RESULTS

Qubit measurements (Google Sheet):
– 20180731_qubit_RNA_crab_isos

NanoDrop Spec Curves:

NanoDrop Table:

Overall, the isolation looks pretty good. The purity looks good (NanoDrop 260/280 ratios) and the absorbance peak at 260nm is exactly where we would want/expect it to be.

The yields (according to the Qubit) are OK. They range from ~37ng – 350ng.

The important part is that this method produced clean RNA, which means the quantification is believable. I think Grace’s earlier RNA isolations using RNAzol RT had too much contamination carried over, leading to incorrect quantification measurements.

Going forward, I think we need to use some sort of isolation kit, however, we will be testing out good, old TriReagent as well.

Mox – Password-less SSH!

The high performance computing (HPC) cluster (called Mox) at Univ. of Washington (UW) frustratingly requires a password when SSH-ing, even when SSH keys are in use. I have a lengthy, unintelligible password that I use for my UW account, so having to type this in any time I want to initiate a new SSH session on Mox is a painful process.

Today, I finally got fed up with how much time I was wasting (granted, it’s minor in the grand scheme of my day) just logging in to Mox, so I spent some time figuring out how to automate password entry for a new SSH session with Mox.

I tried to handle this using the program sshpass, but I couldn’t get it to read my password from a file – it would just hang in limbo after executing the command.

In the end, I came across a bash script that does this perfectly. Steps to implement this on Ubuntu 16.04 LTS:

  1. Install expect: 
    sudo apt install expect
  2. Create following script (taken from this StackExchange solution): 
    
#!/usr/bin/expect

spawn ssh mox
expect "Password:"
send "<UW_password>\r"
interact

    NOTES:

    • I have an ~/.ssh/config file that allows me to use “mox” as an alias for my full SSH command

    • Replace with your own UW password.

  3. Change access to script (set read, write, execute for user only):

    chmod u=rwx,go-rwx
  4. Run script from home directory (saved in home directory): 
    ./mox.sh

Boom! No having to track down password, copy, and paste!

Transposable Element Mapping – Olympia Oyster Genome Assembly, Olurida_v081, using RepeatMasker 4.07

I previously performed this analysis using a different version of our Ostrea lurida genome assembly. Steven asked that I repeat the analysis with a modified version of the genome assembly (Olurida_v081) – only has contigs >1000bp in length.

Genome used: Olurida_v081

I ran RepeatMasker (v4.07) with RepBase-20170127 and RMBlast 2.6.0 four times:

  1. Default settings (i.e. no species select – will use human genome).

  2. Species = Crassostrea gigas (Pacific oyster)

  3. Species = Crassostrea virginica (Eastern oyster)

  4. Species = Ostrea lurida (Olympia oyster)

The idea was to get a sense of how the analyses would differ with species specifications. However, it’s likely that the only species setting that will make any difference will be Run #2 (Crassostrea gigas).

The reason I say this is that RepeatMasker has a built in tool to query which species are available in the RepBase database (e.g.):

RepeatMasker-4.0.7/util/queryRepeatDatabase.pl -species "crassostrea virginica" -stat

Here’s a very brief overview of what that yields:

  • Crassotrea gigas: 792 specific repeats

  • Crassostrea virginica: 4 Crassostrea virginica specific repeats

  • Ostrea lurida: 0 Ostrea lurida specific repeats

All runs were performed on roadrunner.

All commands were documented in a Jupyter Notebook (GitHub):

NOTE: RepeatMasker writes the desired output files (*.out, *.cat.gz, and *.gff) to the same directory that the genome is located in! If you conduct multiple runs with the same genome in the same directory, it will overwrite those files, as they are named using the genome assembly filename.

RESULTS:
RUN 1 (default settings – human genome)

Output folder:

Summary table (text):

Output table (GFF):

SUMMARY TABLE

==================================================
file name: Olurida_v081.fa          
sequences:        159429
total length: 1140787867 bp  (1077373535 bp excl N/X-runs)
GC level:         36.58 %
bases masked:   17954347 bp ( 1.67 %)
==================================================
               number of      length   percentage
               elements*    occupied  of sequence
--------------------------------------------------
SINEs:            16599       978030 bp    0.09 %
      ALUs            1          292 bp    0.00 %
      MIRs          937        72873 bp    0.01 %

LINEs:             3279       752631 bp    0.07 %
      LINE1         172        10882 bp    0.00 %
      LINE2         646        67827 bp    0.01 %
      L3/CR1        659        60327 bp    0.01 %

LTR elements:       569       127808 bp    0.01 %
      ERVL           32         1949 bp    0.00 %
      ERVL-MaLRs     10          490 bp    0.00 %
      ERV_classI    165        17699 bp    0.00 %
      ERV_classII    26         1590 bp    0.00 %

DNA elements:      1911       161957 bp    0.02 %
     hAT-Charlie     74         4216 bp    0.00 %
     TcMar-Tigger   584        24985 bp    0.00 %

Unclassified:        78         9834 bp    0.00 %

Total interspersed repeats:  2030260 bp    0.19 %


Small RNA:         5592       409456 bp    0.04 %

Satellites:         117        21278 bp    0.00 %
Simple repeats:  270784     12935570 bp    1.20 %
Low complexity:   42130      2568284 bp    0.24 %
==================================================

* most repeats fragmented by insertions or deletions
  have been counted as one element
  Runs of >=20 X/Ns in query were excluded in % calcs


The query species was assumed to be homo sapiens  
RepeatMasker Combined Database: Dfam_Consensus-20170127, RepBase-20170127
        
run with rmblastn version 2.6.0+
RUN 2 (species – Crassostrea gigas)

Output folder:

Summary table (text):

Output table (GFF):

SUMMARY TABLE

file name: Olurida_v081.fa          
sequences:        159429
total length: 1140787867 bp  (1077373535 bp excl N/X-runs)
GC level:         36.58 %
bases masked:  152816516 bp ( 14.18 %)
==================================================
               number of      length   percentage
               elements*    occupied  of sequence
--------------------------------------------------
Retroelements       193250     67253771 bp    6.24 %
   SINEs:             2087       284274 bp    0.03 %
   Penelope         158576     56080082 bp    5.21 %
   LINEs:           179430     61300904 bp    5.69 %
    CRE/SLACS            0            0 bp    0.00 %
     L2/CR1/Rex        675       348273 bp    0.03 %
     R1/LOA/Jockey       0            0 bp    0.00 %
     R2/R4/NeSL          7        10781 bp    0.00 %
     RTE/Bov-B        7051      1827344 bp    0.17 %
     L1/CIN4             0            0 bp    0.00 %
   LTR elements:     11733      5668593 bp    0.53 %
     BEL/Pao          1517       871288 bp    0.08 %
     Ty1/Copia          78        72481 bp    0.01 %
     Gypsy/DIRS1      9151      4445789 bp    0.41 %
       Retroviral        0            0 bp    0.00 %

DNA transposons     233691     33727339 bp    3.13 %
   hobo-Activator    17578      1886743 bp    0.18 %
   Tc1-IS630-Pogo    39184      6403235 bp    0.59 %
   En-Spm                0            0 bp    0.00 %
   MuDR-IS905            0            0 bp    0.00 %
   PiggyBac           7261      1003937 bp    0.09 %
   Tourist/Harbinger  8635       823434 bp    0.08 %
   Other (Mirage,        0            0 bp    0.00 %
    P-element, Transib)

Rolling-circles          0            0 bp    0.00 %

Unclassified:       157855     36675484 bp    3.40 %

Total interspersed repeats:   137656594 bp   12.78 %


Small RNA:             222        72690 bp    0.01 %

Satellites:           6260      1238331 bp    0.11 %
Simple repeats:     241081     11662466 bp    1.08 %
Low complexity:      38915      2347827 bp    0.22 %
==================================================

* most repeats fragmented by insertions or deletions
  have been counted as one element
  Runs of >=20 X/Ns in query were excluded in % calcs


The query species was assumed to be crassostrea gigas
RepeatMasker Combined Database: Dfam_Consensus-20170127, RepBase-20170127
        
run with rmblastn version 2.6.0+
RUN 3 (species – Crassostrea virginica)

Output folder:

Summary table (text):

Output table (GFF):

SUMMARY TABLE

file name: Olurida_v081.fa          
sequences:        159429
total length: 1140787867 bp  (1077373535 bp excl N/X-runs)
GC level:         36.58 %
bases masked:   36996910 bp ( 3.43 %)
==================================================
               number of      length   percentage
               elements*    occupied  of sequence
--------------------------------------------------
Retroelements        59806      9886111 bp    0.92 %
   SINEs:            59806      9886111 bp    0.92 %
   Penelope              0            0 bp    0.00 %
   LINEs:                0            0 bp    0.00 %
    CRE/SLACS            0            0 bp    0.00 %
     L2/CR1/Rex          0            0 bp    0.00 %
     R1/LOA/Jockey       0            0 bp    0.00 %
     R2/R4/NeSL          0            0 bp    0.00 %
     RTE/Bov-B           0            0 bp    0.00 %
     L1/CIN4             0            0 bp    0.00 %
   LTR elements:         0            0 bp    0.00 %
     BEL/Pao             0            0 bp    0.00 %
     Ty1/Copia           0            0 bp    0.00 %
     Gypsy/DIRS1         0            0 bp    0.00 %
       Retroviral        0            0 bp    0.00 %

DNA transposons       8720      2230426 bp    0.21 %
   hobo-Activator        0            0 bp    0.00 %
   Tc1-IS630-Pogo        0            0 bp    0.00 %
   En-Spm                0            0 bp    0.00 %
   MuDR-IS905            0            0 bp    0.00 %
   PiggyBac              0            0 bp    0.00 %
   Tourist/Harbinger     0            0 bp    0.00 %
   Other (Mirage,        0            0 bp    0.00 %
    P-element, Transib)

Rolling-circles          0            0 bp    0.00 %

Unclassified:        47005      9434652 bp    0.88 %

Total interspersed repeats:    21551189 bp    2.00 %


Small RNA:           60030      9959172 bp    0.92 %

Satellites:              8         5100 bp    0.00 %
Simple repeats:     259134     12795379 bp    1.19 %
Low complexity:      42184      2581162 bp    0.24 %
==================================================

* most repeats fragmented by insertions or deletions
  have been counted as one element
  Runs of >=20 X/Ns in query were excluded in % calcs


The query species was assumed to be crassostrea virginica
RepeatMasker Combined Database: Dfam_Consensus-20170127, RepBase-20170127
        
run with rmblastn version 2.6.0+
RUN 4 (species – Ostrea lurida)

Output folder:

Summary table (text):

Output table (GFF):

SUMMARY TABLE

==================================================
file name: Olurida_v081.fa          
sequences:        159429
total length: 1140787867 bp  (1077373535 bp excl N/X-runs)
GC level:         36.58 %
bases masked:   15918797 bp ( 1.48 %)
==================================================
               number of      length   percentage
               elements*    occupied  of sequence
--------------------------------------------------
Retroelements            0            0 bp    0.00 %
   SINEs:                0            0 bp    0.00 %
   Penelope              0            0 bp    0.00 %
   LINEs:                0            0 bp    0.00 %
    CRE/SLACS            0            0 bp    0.00 %
     L2/CR1/Rex          0            0 bp    0.00 %
     R1/LOA/Jockey       0            0 bp    0.00 %
     R2/R4/NeSL          0            0 bp    0.00 %
     RTE/Bov-B           0            0 bp    0.00 %
     L1/CIN4             0            0 bp    0.00 %
   LTR elements:         0            0 bp    0.00 %
     BEL/Pao             0            0 bp    0.00 %
     Ty1/Copia           0            0 bp    0.00 %
     Gypsy/DIRS1         0            0 bp    0.00 %
       Retroviral        0            0 bp    0.00 %

DNA transposons          0            0 bp    0.00 %
   hobo-Activator        0            0 bp    0.00 %
   Tc1-IS630-Pogo        0            0 bp    0.00 %
   En-Spm                0            0 bp    0.00 %
   MuDR-IS905            0            0 bp    0.00 %
   PiggyBac              0            0 bp    0.00 %
   Tourist/Harbinger     0            0 bp    0.00 %
   Other (Mirage,        0            0 bp    0.00 %
    P-element, Transib)

Rolling-circles          0            0 bp    0.00 %

Unclassified:            3          189 bp    0.00 %

Total interspersed repeats:         189 bp    0.00 %


Small RNA:             224        73061 bp    0.01 %

Satellites:              8         5100 bp    0.00 %
Simple repeats:     273098     13256460 bp    1.23 %
Low complexity:      42443      2592212 bp    0.24 %
==================================================

* most repeats fragmented by insertions or deletions
  have been counted as one element
  Runs of >=20 X/Ns in query were excluded in % calcs


The query species was assumed to be ostrea lurida 
RepeatMasker Combined Database: Dfam_Consensus-20170127, RepBase-20170127
        
run with rmblastn version 2.6.0+

Library Construction – Geoduck Water Filter Metagenome with Nextera DNA Flex Kit (Illumina)

Made Illumina libraries with goeduck metagenome water filter DNA I previously isolated on:

We used a free Nextera DNA Flex Kit (Illumina) that we won in a contest held by Illumina!

Followed the manufacturer’s protocol for input DNA quantities <10ng with the following changes/notes:

  • PCR steps performed in 200uL thin-walled PCR tubes.

  • Magnetic separations were performed in 1.7mL snap cap tubes.

  • Thermalcycler: PTC-200 (MJ Research)

  • Magnet: DynaMag 2 (Invitrogen)

See the Library Calcs sheet (link below) for original sample names and subsequent library sample names.

IMPORTANT!

The sheet also contains the indexes used for each library. This info will be necessary for sequencing facility.

Library Calcs (Google Sheet):

Links to the Illumina manuals are below:

After library construction was completed, individual libraries were quantified on the Roberts Lab Qubit 3.0 (Invitrogen) with the Qubit 1x dsDNA HS Assay Kit.

2uL of each sample was used for each assay.

Library quality was assessed using the Seeb Lab 2100 Bioanalyzer (Agilent) with a High Sensitivity DNA Kit, using 1uL of each sample.

Libraries were stored in the small -20C in FTR213:

Results:

Qubit Raw Data (Google Sheet):

Bioanalyzer File (XAD):

All libraries have DNA in them, so that’s good!

Except for one library (Library Geoduck MG #04 is bad), the other libraries look OK (i.e. not great). Compared to the example on Pg. 12 in the manual, these libraries all have some extra high molecular weight stuff.

When selecting the range listed in the Nextera Kit manual, the average fragment size is ~530bp – the expected size should be ~600bp.

Spoke with Steven about Library Geoduck MG #04 and we’ve opted to just leave it out.

All other samples were pooled into a single samples according to the manufacturer’s protocol.

This pooled sample was stored in the same -20C box as above, in position I4.

UPDATE 20180808

After some confusion with the sequencing facility, I contacted Illumina regarding adapter sequences. I used the sequences provided for the Nextera DNA 24 CD Indexes (which was the index kit we used) on p.18 of the Illumina Index Adapter Pooling Guide.

As it turns out, these sequences are incorrect. The correct sequences are on p.12 of that document (the Nextera DNA 96 CD Indexes).

I’ve updated the Google Sheet (linked above) to reflect the correct index sequences.

Email from Illumina is below. Even though he specifically references the H705 adapter, the correct sequence information for all i7 index adapters is found on p.12.

Hi Sam,

Thanks for the clarification! For the index sequence H705, this sequence is incorrect in the Index Adapters Pooling Guide. The correct information is found on page 12 of the same document and should be:

H705 “AGGAGTCC” (Bases in Adapter) and “GGACTCCT” (bases for sample sheet.

This is also consistent with the Illumina Adapters letter.

We have provided this feed back to our colleagues to update the document so that all the information is consistent.

Thanks for your patience and understanding while we evaluated this issue. If we do have any other questions or concerns, please let us know and we would be happy to discuss this further.

Best,

Russell

Russell Chan, Ph.D.

Technical Applications Scientist

Illumina Technical Support

Telephone available 24 hours

Monday through Friday

Technical Bulletins: https://support.illumina.com/bulletins.html

Trainings: http://support.illumina.com/traidexes

BS-seq Mapping – Olympia oyster bisulfite sequencing: Bismark Continued

Previously took the analysis just through the mapping, but didn’t realize Steven wanted me to fully process the data.

So, as en exercise, I followed through with deduplication and sorting of the BAM files.

Then, ran a quick analysis using MethylKit in R. The analysis simply copied what Steven had done with another data set and I haven’t examined it very thoroughly, so am not well-versed on what it’s doing and/or why.

Jupyter Notebook (GitHub):

R Studio Project (download the folder, load project in R Studio, and then run the script in the scripts subdirectory to run the analysis):

Will take the full data sets through this whole pipeline.

Transposable Element Mapping – Crassostrea virginica NCBI Genome Assembly using RepeatMasker 4.07

Genome used: NCBI GCA_002022765.4_C_virginica-3.0

I ran RepeatMasker (v4.07) with RepBase-20170127 and RMBlast 2.6.0 with species set to Crassotrea virginica.

All commands were documented in a Jupyter Notebook (GitHub):

RESULTS:

Output folder:

Output table (GFF):

Summary table (text):

==================================================
file name: GCF_002022765.2_C_virginica-3.0_genomic.fasta
sequences:            11
total length:  684741128 bp  (684675328 bp excl N/X-runs)
GC level:         34.83 %
bases masked:   46637065 bp ( 6.81 %)
==================================================
               number of      length   percentage
               elements*    occupied  of sequence
--------------------------------------------------
Retroelements        43139      8952068 bp    1.31 %
   SINEs:            43139      8952068 bp    1.31 %
   Penelope              0            0 bp    0.00 %
   LINEs:                0            0 bp    0.00 %
    CRE/SLACS            0            0 bp    0.00 %
     L2/CR1/Rex          0            0 bp    0.00 %
     R1/LOA/Jockey       0            0 bp    0.00 %
     R2/R4/NeSL          0            0 bp    0.00 %
     RTE/Bov-B           0            0 bp    0.00 %
     L1/CIN4             0            0 bp    0.00 %
   LTR elements:         0            0 bp    0.00 %
     BEL/Pao             0            0 bp    0.00 %
     Ty1/Copia           0            0 bp    0.00 %
     Gypsy/DIRS1         0            0 bp    0.00 %
       Retroviral        0            0 bp    0.00 %

DNA transposons       3538      1564942 bp    0.23 %
   hobo-Activator        0            0 bp    0.00 %
   Tc1-IS630-Pogo        0            0 bp    0.00 %
   En-Spm                0            0 bp    0.00 %
   MuDR-IS905            0            0 bp    0.00 %
   PiggyBac              0            0 bp    0.00 %
   Tourist/Harbinger     0            0 bp    0.00 %
   Other (Mirage,        0            0 bp    0.00 %
    P-element, Transib)

Rolling-circles          0            0 bp    0.00 %

Unclassified:        65151     23982146 bp    3.50 %

Total interspersed repeats:    34499156 bp    5.04 %


Small RNA:           43353      8992879 bp    1.31 %

Satellites:              1          222 bp    0.00 %
Simple repeats:     232627     10544162 bp    1.54 %
Low complexity:      29762      1561018 bp    0.23 %
==================================================

* most repeats fragmented by insertions or deletions
  have been counted as one element
  Runs of >=20 X/Ns in query were excluded in % calcs


The query species was assumed to be crassostrea virginica
RepeatMasker Combined Database: Dfam_Consensus-20170127, RepBase-20170127
        
run with rmblastn version 2.6.0+

Read Mapping – Olympia oyster 2bRAD Data with Bowtie2 (on Mox)

Per Steven’s request, mapped our Olympia oyster 2bRAD data.

Mapped to:

This was run on our Mox computing node.

Slurm script: 20180515_oly_2bRAD_bowtie2_mapping.sh

The script is far too long to paste here, due to the shear number of input files. However, here’s a snippet to show the command and options that were used:


/gscratch/srlab/programs/bowtie2-2.3.4.1-linux-x86_64/bowtie2 \
--threads 24 \
--no-unal \
--score-min L,16,1 \
--local \
-L 16 \
-S /gscratch/srlab/sam/outputs/20180515_oly_2bRAD_bowtie2_mapping/20180515_oly_2bRAD_bowtie2_mapping.sam \
-x /gscratch/srlab/sam/data/O_lurida/oly_genome_assemblies/20180515_oly_bowtie2_pbjelly_sjw_01_genome_index/pbjelly_sjw_01_ref \
-U

See the linked Slurm script above for the entire thing.

RESULTS:

Output folder:

SAM file (104GB)

Mapping summary:


20180515_oly_2bRAD_bowtie2_mapping$ cat slurm-180337.out 
729797535 reads; of these:
  729797535 (100.00%) were unpaired; of these:
    273989476 (37.54%) aligned 0 times
    310581308 (42.56%) aligned exactly 1 time
    145226751 (19.90%) aligned >1 times
62.46% overall alignment rate

Transposable Element Mapping – Olympia Oyster Genome Assembly using RepeatMasker 4.07

Steven wanted transposable elements (TEs) in the Olympia oyster genome identified.

After some minor struggles, I was able to get RepeatMasker installed on on both of our Apple Xserves (emu & roadrunner; running Ubuntu 16.04LTS).

Genome used: pbjelly_sjw_01

I ran RepeatMasker (v4.07) with RepBase-20170127 and RMBlast 2.6.0 four times:

  1. Default settings (i.e. no species select – will use human genome).

  2. Species = Crassostrea gigas (Pacific oyster)

  3. Species = Crassostrea virginica (Eastern oyster)

  4. Species = Ostrea lurida (Olympia oyster)

The idea was to get a sense of how the analyses would differ with species specifications. However, it’s likely that the only species setting that will make any difference will be Run #2 (Crassostrea gigas).

The reason I say this is that RepeatMasker has a built in tool to query which species are available in the RepBase database (e.g.):

RepeatMasker-4.0.7/util/queryRepeatDatabase.pl -species "crassostrea virginica" -stat

Here’s a very brief overview of what that yields:

  • Crassotrea gigas: 792 specific repeats

  • Crassostrea virginica: 4 Crassostrea virginica specific repeats

  • Ostrea lurida: 0 Ostrea lurida specific repeats

All runs were performed on roadrunner.

All commands were documented in a Jupyter Notebook (GitHub):

NOTE: RepeatMasker writes the desired output files (*.out, *.cat.gz, and *.gff) to the same directory that the genome is located in! If you conduct multiple runs with the same genome in the same directory, it will overwrite those files, as they are named using the genome assembly filename.

RESULTS:
RUN 1 (default settings – human genome)

Output folder:

Summary table (text):

Output table (GFF):

SUMMARY TABLE

==================================================
file name: jelly.out.fasta          
sequences:        696946
total length: 1253001795 bp  (1172226648 bp excl N/X-runs)
GC level:         36.51 %
bases masked:   20002806 bp ( 1.71 %)
==================================================
               number of      length   percentage
               elements*    occupied  of sequence
--------------------------------------------------
SINEs:            17794      1061170 bp    0.09 %
      ALUs          363        31340 bp    0.00 %
      MIRs         1166        92129 bp    0.01 %

LINEs:             4456       888114 bp    0.08 %
      LINE1         976       103929 bp    0.01 %
      LINE2         813        82891 bp    0.01 %
      L3/CR1        699        63627 bp    0.01 %

LTR elements:      1187       199118 bp    0.02 %
      ERVL          155        15828 bp    0.00 %
      ERVL-MaLRs    200        20737 bp    0.00 %
      ERV_classI    379        42833 bp    0.00 %
      ERV_classII    66         6896 bp    0.00 %

DNA elements:      2290       196866 bp    0.02 %
     hAT-Charlie    190        15468 bp    0.00 %
     TcMar-Tigger   732        37473 bp    0.00 %

Unclassified:       101        12946 bp    0.00 %

Total interspersed repeats:  2358214 bp    0.20 %


Small RNA:         5954       433422 bp    0.04 %

Satellites:         366        55705 bp    0.00 %
Simple repeats:  310641     14322152 bp    1.22 %
Low complexity:   47381      2844279 bp    0.24 %
==================================================

* most repeats fragmented by insertions or deletions
  have been counted as one element
  Runs of >=20 X/Ns in query were excluded in % calcs


The query species was assumed to be homo sapiens  
RepeatMasker Combined Database: Dfam_Consensus-20170127, RepBase-20170127
        
run with rmblastn version 2.6.0+
RUN 2 (species – Crassostrea gigas)

Output folder:

Summary table (text):

Output table (GFF):

SUMMARY TABLE

==================================================
file name: jelly.out.fasta          
sequences:        696946
total length: 1253001795 bp  (1172226648 bp excl N/X-runs)
GC level:         36.51 %
bases masked:  160759267 bp ( 13.71 %)
==================================================
               number of      length   percentage
               elements*    occupied  of sequence
--------------------------------------------------
Retroelements       213132     69887654 bp    5.96 %
   SINEs:             2374       311974 bp    0.03 %
   Penelope         171792     57862186 bp    4.94 %
   LINEs:           195605     63430615 bp    5.41 %
    CRE/SLACS            0            0 bp    0.00 %
     L2/CR1/Rex        731       357995 bp    0.03 %
     R1/LOA/Jockey       0            0 bp    0.00 %
     R2/R4/NeSL         13        11377 bp    0.00 %
     RTE/Bov-B        8085      1948581 bp    0.17 %
     L1/CIN4             0            0 bp    0.00 %
   LTR elements:     15153      6145065 bp    0.52 %
     BEL/Pao          2119       955773 bp    0.08 %
     Ty1/Copia         101        75372 bp    0.01 %
     Gypsy/DIRS1     11776      4815361 bp    0.41 %
       Retroviral        0            0 bp    0.00 %

DNA transposons     256292     35689117 bp    3.04 %
   hobo-Activator    19847      2059651 bp    0.18 %
   Tc1-IS630-Pogo    43269      6806311 bp    0.58 %
   En-Spm                0            0 bp    0.00 %
   MuDR-IS905            0            0 bp    0.00 %
   PiggyBac           7935      1060296 bp    0.09 %
   Tourist/Harbinger  9503       887332 bp    0.08 %
   Other (Mirage,        0            0 bp    0.00 %
    P-element, Transib)

Rolling-circles          0            0 bp    0.00 %

Unclassified:       174943     38299211 bp    3.27 %

Total interspersed repeats:   143875982 bp   12.27 %


Small RNA:             280        78768 bp    0.01 %

Satellites:           7383      1362194 bp    0.12 %
Simple repeats:     278809     12982714 bp    1.11 %
Low complexity:      44078      2622506 bp    0.22 %
==================================================

* most repeats fragmented by insertions or deletions
  have been counted as one element
  Runs of >=20 X/Ns in query were excluded in % calcs


The query species was assumed to be crassostrea gigas
RepeatMasker Combined Database: Dfam_Consensus-20170127, RepBase-20170127
        
run with rmblastn version 2.6.0+
RUN 3 (species – Crassostrea virginica)

Output folder:

Summary table (text):

Output table (GFF):

SUMMARY TABLE

==================================================
file name: jelly.out.fasta          
sequences:        696946
total length: 1253001795 bp  (1172226648 bp excl N/X-runs)
GC level:         36.51 %
bases masked:   39598953 bp ( 3.38 %)
==================================================
               number of      length   percentage
               elements*    occupied  of sequence
--------------------------------------------------
Retroelements        63882     10327611 bp    0.88 %
   SINEs:            63882     10327611 bp    0.88 %
   Penelope              0            0 bp    0.00 %
   LINEs:                0            0 bp    0.00 %
    CRE/SLACS            0            0 bp    0.00 %
     L2/CR1/Rex          0            0 bp    0.00 %
     R1/LOA/Jockey       0            0 bp    0.00 %
     R2/R4/NeSL          0            0 bp    0.00 %
     RTE/Bov-B           0            0 bp    0.00 %
     L1/CIN4             0            0 bp    0.00 %
   LTR elements:         0            0 bp    0.00 %
     BEL/Pao             0            0 bp    0.00 %
     Ty1/Copia           0            0 bp    0.00 %
     Gypsy/DIRS1         0            0 bp    0.00 %
       Retroviral        0            0 bp    0.00 %

DNA transposons       9433      2307292 bp    0.20 %
   hobo-Activator        0            0 bp    0.00 %
   Tc1-IS630-Pogo        0            0 bp    0.00 %
   En-Spm                0            0 bp    0.00 %
   MuDR-IS905            0            0 bp    0.00 %
   PiggyBac              0            0 bp    0.00 %
   Tourist/Harbinger     0            0 bp    0.00 %
   Other (Mirage,        0            0 bp    0.00 %
    P-element, Transib)

Rolling-circles          0            0 bp    0.00 %

Unclassified:        51558      9836468 bp    0.84 %

Total interspersed repeats:    22471371 bp    1.92 %


Small RNA:           64164     10406776 bp    0.89 %

Satellites:             10         5985 bp    0.00 %
Simple repeats:     298612     14185090 bp    1.21 %
Low complexity:      47510      2866522 bp    0.24 %
==================================================

* most repeats fragmented by insertions or deletions
  have been counted as one element
  Runs of >=20 X/Ns in query were excluded in % calcs


The query species was assumed to be crassostrea virginica
RepeatMasker Combined Database: Dfam_Consensus-20170127, RepBase-20170127
        
run with rmblastn version 2.6.0+
RUN 4 (species – Ostrea lurida)

Output folder:

Summary table (text):

Output table (GFF):

SUMMARY TABLE

==================================================
file name: jelly.out.fasta          
sequences:        696946
total length: 1253001795 bp  (1172226648 bp excl N/X-runs)
GC level:         36.51 %
bases masked:   17617763 bp ( 1.50 %)
==================================================
               number of      length   percentage
               elements*    occupied  of sequence
--------------------------------------------------
Retroelements            0            0 bp    0.00 %
   SINEs:                0            0 bp    0.00 %
   Penelope              0            0 bp    0.00 %
   LINEs:                0            0 bp    0.00 %
    CRE/SLACS            0            0 bp    0.00 %
     L2/CR1/Rex          0            0 bp    0.00 %
     R1/LOA/Jockey       0            0 bp    0.00 %
     R2/R4/NeSL          0            0 bp    0.00 %
     RTE/Bov-B           0            0 bp    0.00 %
     L1/CIN4             0            0 bp    0.00 %
   LTR elements:         0            0 bp    0.00 %
     BEL/Pao             0            0 bp    0.00 %
     Ty1/Copia           0            0 bp    0.00 %
     Gypsy/DIRS1         0            0 bp    0.00 %
       Retroviral        0            0 bp    0.00 %

DNA transposons          0            0 bp    0.00 %
   hobo-Activator        0            0 bp    0.00 %
   Tc1-IS630-Pogo        0            0 bp    0.00 %
   En-Spm                0            0 bp    0.00 %
   MuDR-IS905            0            0 bp    0.00 %
   PiggyBac              0            0 bp    0.00 %
   Tourist/Harbinger     0            0 bp    0.00 %
   Other (Mirage,        0            0 bp    0.00 %
    P-element, Transib)

Rolling-circles          0            0 bp    0.00 %

Unclassified:            3          189 bp    0.00 %

Total interspersed repeats:         189 bp    0.00 %


Small RNA:             282        79165 bp    0.01 %

Satellites:             10         5985 bp    0.00 %
Simple repeats:     313082     14662647 bp    1.25 %
Low complexity:      47785      2878201 bp    0.25 %
==================================================

* most repeats fragmented by insertions or deletions
  have been counted as one element
  Runs of >=20 X/Ns in query were excluded in % calcs


The query species was assumed to be ostrea lurida 
RepeatMasker Combined Database: Dfam_Consensus-20170127, RepBase-20170127
        
run with rmblastn version 2.6.0+