DML Analysis Part 23

DMR-mRNA gene product information

Since I didn’t get much information from my previous gene enrichment, I thought I would start describing the function of coding regions with DMRs in them. When I looked at the DMR-mRNA overlap file, I saw that there was gene product information buried in the last column:

ID=rna48;Parent=gene35;Dbxref=GeneID:111114201,Genbank:XM_022452489.1;Name=XM_022452489.1;Note=The sequence of the model RefSeq transcript was modified relative to this genomic sequence to represent the inferred CDS: inserted 2 bases in 2 codons;exception=unclassified transcription discrepancy;gbkey=mRNA;gene=LOC111114201;model_evidence=Supporting evidence includes similarity to: 4 Proteins%2C and 99%25 coverage of the annotated genomic feature by RNAseq alignments%2C including 9 samples with support for all annotated introns;product=vacuolar protein sorting-associated protein 13B-like;transcript_id=XM_022452489.1

My first step was to isolate the product= information from this column. The easiest thing to do would be to use awk to separate the text into multiple columns based on a ; delimiter. However, there are different numbers of ; in each line, so the product informaiton would not consistently be in the same column throughout the document. I wanted to separate out all product information, either by creating a custom delimiter or extracting all information after product=. I figured there’d be an elegant way to do this with bash, so I posted this issue. Unfortunately Sam couldn’t help me with a solution! I took the easy way out and used Excel.

I created a duplicate column, replaced product= with >, then used > as a delimiter to separate product information from the rest of the column. I then used ; as a delimiter with the column I just generated to separate the product information from the transcript ID. Finally, I deleted columns without product information that I generated throughout this process. My final document, found here, looks like this:

screen shot 2019-02-25 at 4 14 47 pm

I know you can use sed for a find-and-replace to do something similar in bash, but I couldn’t get that to work:

screen shot 2019-02-25 at 4 02 13 pm

Now that I had the product information isolated, I wanted to create a new document with summary information (gene product, percent methylation difference, number of transcript variants the DMR was found in). I figured this summary document would be a good starting place when I start writing. The summary document can be found here. DMRs were found in interesting genes, including calcium uptake (could help with calcification), cilia and flagella associated protein (sperm motility, cellular structure), cytochrome P450 (oxidative stress protein), tubulin-specific chaperones (motility-related), telomere-associated protein (could be related to cell replication and apoptosis), sperm-tail PG-rich repeat-containing protein (no idea what this does but my guess is that it’s sperm-related), and zygotic DNA replication. There were also 37 uncharacterized gene products.

Going forward

  1. Repeat this process with DMR-exon, DMR-intron, and DMR-TE overlaps
  2. Visualize gene product information
  3. Relate this information to gene enrichment
Written on February 26, 2019