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Please help!! Completely new to pre-processing Drop-Seq SRA file from database
Dear all great helpers,
I'm completely new to Drop-seq analysis, and I do have no clue how to preprocess Drop-Seq data acquired from SRA database. For example, I have tried downloading and spiting SRR11014434 data file. Now I have two fastq files as follows: SRR11014434_1.fastq and SRR11014434_2.fastq.
I've started by learning from the Drop-seq cookbook (https://github.com/broadinstitute/Dr...t_Cookbook.pdf). As far as I understand the SRR11014434_2.fastq file contains data about the UMI and Cell barcode, while the SRR11014434_1.fastq file contains expression data of the cell.
Since the cookbook demonstrate step-by-step starting from raw read counts acquired from sequencer, I'm now totally confused with what I'm doing. Some of the very basic but critical questions are as follows:
1) Is the data already demultiplexed?
2) Am I supposed to align SRR11014434_2.fastq by STAR? What should I do after this step? The cookbook talked about merging mapped and unmapped BAM file, tagging exon/gene annotations. But I totally how am I suppose to do this without the unmapped bam file (All I could think about is trying to include unmaaped read the output sam file acquired from STAR using --outSAMunmapped Within option and use it as the merged file).
Please help me!!
Kaj
I'm completely new to Drop-seq analysis, and I do have no clue how to preprocess Drop-Seq data acquired from SRA database. For example, I have tried downloading and spiting SRR11014434 data file. Now I have two fastq files as follows: SRR11014434_1.fastq and SRR11014434_2.fastq.
I've started by learning from the Drop-seq cookbook (https://github.com/broadinstitute/Dr...t_Cookbook.pdf). As far as I understand the SRR11014434_2.fastq file contains data about the UMI and Cell barcode, while the SRR11014434_1.fastq file contains expression data of the cell.
Since the cookbook demonstrate step-by-step starting from raw read counts acquired from sequencer, I'm now totally confused with what I'm doing. Some of the very basic but critical questions are as follows:
1) Is the data already demultiplexed?
2) Am I supposed to align SRR11014434_2.fastq by STAR? What should I do after this step? The cookbook talked about merging mapped and unmapped BAM file, tagging exon/gene annotations. But I totally how am I suppose to do this without the unmapped bam file (All I could think about is trying to include unmaaped read the output sam file acquired from STAR using --outSAMunmapped Within option and use it as the merged file).
Please help me!!
Kaj