--- name: bio-epitranscriptomics-m6a-peak-calling description: Call m6A peaks from MeRIP-seq IP vs input comparisons. Use when identifying m6A modification sites from methylated RNA immunoprecipitation data. tool_type: mixed primary_tool: exomePeak2 --- # m6A Peak Calling ## exomePeak2 (Recommended) ```r library(exomePeak2) # Peak calling with biological replicates result <- exomePeak2( bam_ip = c('IP_rep1.bam', 'IP_rep2.bam'), bam_input = c('Input_rep1.bam', 'Input_rep2.bam'), gff = 'genes.gtf', genome = 'hg38', paired_end = TRUE ) # Export peaks exportResults(result, format = 'BED') ``` ## MACS3 Alternative ```bash # Call peaks treating input as control macs3 callpeak \ -t IP_rep1.bam IP_rep2.bam \ -c Input_rep1.bam Input_rep2.bam \ -f BAMPE \ -g hs \ -n m6a_peaks \ --nomodel \ --extsize 150 \ -q 0.05 ``` ## MeTPeak ```r library(MeTPeak) # GTF-aware peak calling metpeak( IP_BAM = c('IP_rep1.bam', 'IP_rep2.bam'), INPUT_BAM = c('Input_rep1.bam', 'Input_rep2.bam'), GENE_ANNO_GTF = 'genes.gtf', OUTPUT_DIR = 'metpeak_output' ) ``` ## Peak Filtering ```bash # Filter by fold enrichment and q-value # FC > 2, q < 0.05 typical thresholds awk '$7 > 2 && $9 < 0.05' peaks.xls > filtered_peaks.bed ``` ## Related Skills - merip-preprocessing - Prepare data for peak calling - m6a-differential - Compare peaks between conditions - chip-seq/peak-calling - Similar concepts