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🧬 Multi-Omics Architecture DNA • RNA • Protein • Metabolite Systems Biology Framework

The Multi-Omics Landscape: Genomics, Transcriptomics, Proteomics & Metabolomics

Biological systems operate through dynamic, multi-layered regulatory networks. Explore comprehensive guides, technologies, computational toolchains, and data architectures across every major omics discipline—from the genomic blueprint to the metabolic phenotype.

🧬 Genomics 📊 Transcriptomics 🔬 Proteomics 🧪 Metabolomics 🧬 Epigenomics 🦠 Metagenomics 🌱 Plant & Polyploid 🌐 Multi-Omics Integration
🔬 MULTI-OMICS PRODUCTION MATRIX · v3.2

Functional & Regulatory Omics Workbench

Select an omic layer to inspect its end-to-end tool stack, statistical normalization model, and toy dataset.

Raw Input & Conversion
Thermo .raw / Bruker .d → .mzML
ThermoRawFileParser / msconvert
Primary Quantification Engine
DIA-NN / FragPipe (MSFragger)
In-silico spectral lib + MaxLFQ MBR
Normalization & Statistics
VSN + MinProb/QRILC + Limma
Bioconductor DEP / MSstats / KSEA
Practice Dataset & Specs
proteomics_mini_diann.tsv (4.2 MB)
⚡ 16–32 Cores · 64 GB RAM

🔄 The Central Dogma & The Hierarchy of Life

Each omics layer captures a unique phase in the flow of biological information. Combining these orthogonal dimensions provides an unprecedented systems-level view of health and disease:

The Central Dogma & Multi-Omics Information Flow Scientific diagram depicting the flow of biological information from DNA (Genomics) through RNA (Transcriptomics) and Proteins (Proteomics) to Metabolites (Metabolomics), regulated by Epigenomics and Microbiome. 1. GENOMICS (DNA) The Static Blueprint 3.2 Gb • 23 Chr Pairs • SNVs • NovaSeq X (Short-Read) • PacBio HiFi / ONT • BWA-MEM2 • GATK4 Transcription RNA Pol II 2. TRANSCRIPTOMICS m7G AAAA The Dynamic Message Isoforms • scRNA • Spatial • STAR • Salmon • DESeq2 • 10x Chromium • Seurat • Visium • Xenium ST Translation Ribosome 80S 3. PROTEOMICS P The Cellular Machinery Abundance • PTMs • Folding • LC-MS/MS • Orbitrap • MaxQuant • DIA-NN • AlphaFold 3 • ESMFold Enzymatic Metabolism 4. METABOLOMICS The Final Phenotype Flux • Lipids • Pathway State • Untargeted LC/GC-MS • XCMS • MetaboAnalyst • KEGG • HMDB 5.0
Figure 1.1: The Multi-Omics Continuum of Life — Orthogonal information flow from genomic sequence to metabolic phenotype, orchestrated by transcriptional regulation, ribosomal translation, and biochemical pathway flux.
Layer 1: The Blueprint

Genomics (DNA)

What can happen: Static genetic code, germline mutations, somatic variants, and structural rearrangements.

Layer 2: The Message

Transcriptomics (RNA)

What appears to be happening: Dynamic gene expression levels, alternative splicing, non-coding RNAs, and single-cell states.

Layer 3: The Machinery

Proteomics (Proteins)

What is doing the work: Protein abundance, 3D structures, post-translational modifications (PTMs), and enzymatic complexes.

Layer 4: The Phenotype

Metabolomics (Small Mol.)

What has actually happened: Cellular metabolites, biochemical pathway flux, lipids, sugars, and environmental readouts.

🧬 1. Genomics: Deciphering the DNA Blueprint

DNA • Variants • Assembly

Genomics investigates the complete genetic complement of an organism. Modern computational genomics revolves around high-throughput sequencing (NGS), aligning billions of short or long reads to human reference genomes (GRCh38, T2T-CHM13), and discovering genetic variations that govern disease, development, and evolution.

Sequencing Architectures & Genomic Variant Spectrum Comparative schematic of Short-Read Illumina SBS vs Long-Read PacBio HiFi and Oxford Nanopore, and classification of single nucleotide variants, indels, and structural rearrangements. A. Illumina SBS (Short-Read) Grafted Oligo Lawn (Flow Cell) Bridge Amplification & SBS Reversible 3'-O-azidomethyl terminators 2×150 bp • Q30 >90% • NovaSeq X B. Long-Read Single-Molecule PacBio HiFi CCS 15-20 kb hairpins • >Q30 accuracy pA Ionic Shift Resolves Repeats • Structural Variants Centromeres • Telomeres • T2T Pangenomics 10 kb – 100+ kb • hifiasm / Flye C. Genomic Variant Classification 1. SNV: C T G A G C T A → Mut: G 2. Indel: A T +CAG G C A Insertion/Del 3. CNV: Tandem Dup (2x) 4. SV: Translocation GATK4 HaplotypeCaller • DeepVariant VCF / BCF • Ensembl VEP • ClinVar
Figure 1.2: High-Throughput Sequencing Chemistries & Variant Detection Spectrum — Short-read Illumina SBS cluster optics, long-read single-molecule real-time architectures, and resolution of variant classes from SNVs to multi-megabase structural translocations.

Sequencing Platforms

Illumina NovaSeq X (2×150 bp short reads, Q30+ accuracy), Pacific Biosciences (PacBio) HiFi long reads (15-20 kb, >99.9% accuracy), and Oxford Nanopore (ONT) ultra-long reads for resolving complex repeats and telomeres.

Compare NGS Technologies →

Variant Discovery (SNVs, Indels, SVs)

Standardized alignment with BWA-MEM2 or Minimap2, coordinate sorting and duplicate marking with samtools, and variant calling using GATK HaplotypeCaller or Google DeepVariant.

Practical Genomics Track →

De Novo Genome Assembly

Reconstructing complete chromosomal contigs using overlap-layout-consensus (OLC) or de Bruijn graphs (hifiasm, Flye, SPAdes) combined with optical mapping and Hi-C scaffolding.

Genome Assembly Guide →

📊 2. Transcriptomics: Profiling the Expressed Genome

RNA-Seq • Single-Cell • Spatial

Transcriptomics captures the quantity and identity of all RNA transcripts (mRNA, lncRNA, miRNA) active in a biological specimen at a given snapshot in time. It measures dynamic responses to environmental stimuli, drugs, and genetic perturbations.

Bulk RNA-Seq Splicing & Single-Cell Resolution Schematic depicting RNA alternative splicing coverage tracks with Sashimi plot junction arcs and 10x Chromium single-cell microfluidics with UMAP cell clustering. A. Bulk RNA-Seq Splicing Architecture (Sashimi Plot) Exon 1 Exon 2 (Alt) Exon 3 1,240 reads 1,180 reads Skipped: 312 reads (Ψ = 0.79) STAR • Salmon • tximport • DESeq2 • rMATS B. 10x Chromium Single-Cell & Spatial UMAP UMAP_1 UMAP_2 T-Cells B-Cells Monocytes NK Cells 1. Cell Ranger Count Barcode + UMI De-dup 2. Seurat v5 SCTransform Variance Stabilization 3. scVI Generative Batch Latent Space Integration 10x Chromium • Seurat • Scanpy • Visium • Xenium
Figure 1.3: Transcriptomics Quantification Modes — Bulk RNA-Seq exon splicing coverage models (Sashimi plot) juxtaposed with single-cell droplet microfluidic barcoding and 2D UMAP non-linear manifold clustering.

Bulk RNA-Seq & Differential Expression

Splice-aware alignment with STAR or pseudo-alignment with Salmon/Kallisto. Negative binomial dispersion modeling and gene shrinkage with DESeq2 and edgeR in R.

Transcriptomics Guide →

Single-Cell RNA-Seq (scRNA-seq)

Droplet microfluidics (10x Genomics Chromium) capturing single-cell transcriptomes with UMIs. Cellular heterogeneity clustering and trajectory modeling via Seurat and Scanpy.

Single-Cell Course (13 Ch) →

Spatial Transcriptomics

Preserving the 2D architectural coordinates of gene expression in intact histology tissue sections using 10x Visium, Xenium In Situ, and NanoString CosMx.

Spatial Biology Module →

🔬 3. Quantitative Proteomics: DIA / DDA & Phosphoproteomics

Mass Spec • 3D Structures • PTMs

Proteomics measures the ultimate functional machinery of the cell. Because post-transcriptional attenuation and protein degradation decouple mRNA expression from protein abundance, quantitative liquid chromatography tandem mass spectrometry (LC-MS/MS) provides direct insight into active signaling cascades, post-translational modifications (PTMs), and druggable target complexes.

Standard 5-Stage Architecture

Quantitative Proteomics Pipeline (DIA / DDA & Phosphoproteomics)

📦 Toy Dataset: proteomics_mini_diann_report.tsv (500 Proteins)
STAGE 1

Raw Conversion & Peak Centroiding

Convert proprietary vendor files (.raw, .d) to open indexed centroided .mzML using ThermoRawFileParser or ProteoWizard msconvert.

STAGE 2

Spectral Library & Quantification

DDA (LFQ/TMT): MSFragger + Philosopher + IonQuant.
DIA: Library-free deep learning in-silico spectral library prediction directly from FASTA proteome in DIA-NN.

STAGE 3

QC & Hybrid Imputation

Filter reverse decoys and contaminants (cRAP), enforce ≥2 unique peptides, apply Variance Stabilizing Normalization (VSN), and impute left-censored MNAR values via MinProb / QRILC.

STAGE 4

Differential Abundance

Linear modeling via MSstats or empirical Bayes moderated t-testing in limma / DEP (|log2FC| > 1, Benjamini-Hochberg FDR < 0.05).

STAGE 5

Phospho & PPI Networks

Kinase-Substrate Enrichment Analysis via KSEAapp for phosphoproteomics and protein-protein interaction (PPI) network hub clustering via STRINGdb / Cytoscape.

Step 01: Raw Vendor File Standardization (ThermoRawFileParser)
# Convert all Thermo .raw files in directory to indexed centroided .mzML (-p = peak picking)
ThermoRawFileParser.sh   -d ./raw_spectra/   -o ./mzml_centroided/   -f 2   -g   -p
Step 02: Library-Free DIA-NN Execution (Two-Pass Deep Learning)
# Step 2A: Generate in-silico predicted spectral library (.predicted.speclib) from FASTA
diann   --lib ""   --threads 32   --verbose 1   --out-lib reference_insilico.speclib   --gen-spec-lib   --predictor   --fasta reference_proteome_canonical.fasta   --fasta-search   --min-fr-mz 200 --max-fr-mz 1800   --min-pep-len 7 --max-pep-len 30   --min-pr-mz 300 --max-pr-mz 1800   --min-pr-charge 1 --max-pr-charge 4   --cut K*,R* --missed-cleavages 1   --unimod4   --var-mods 1 --var-mod UniMod:35,15.994915,M

# Step 2B: Quantify samples against the predicted library with MBR (--reanalyse) & MaxLFQ
diann   --f ./mzml_centroided/ctrl_01.mzML ./mzml_centroided/ctrl_02.mzML ./mzml_centroided/ctrl_03.mzML       ./mzml_centroided/treat_01.mzML ./mzml_centroided/treat_02.mzML ./mzml_centroided/treat_03.mzML   --lib reference_insilico.speclib.predicted.speclib   --threads 32   --out diann_report.tsv   --qvalue 0.01   --matrices   --pg-level 1   --reanalyse   --smart-profiling
Toy Dataset (proteomics_mini_diann_report.tsv)
Protein.Group	Genes	Ctrl_1	Ctrl_2	Ctrl_3	Treat_1	Treat_2	Treat_3	Phospho_Site
P04637	TP53	2450000	2510000	2390000	8900000	9120000	8850000	S315-p
P38398	BRCA1	1820000	1790000	1850000	1950000	1880000	1910000	S1524-p
P00533	EGFR	6200000	6350000	6120000	1200000	1150000	1280000	Y1068-p
P42224	STAT1	3100000	2980000	3250000	7400000	7650000	7300000	Y701-p
P60709	ACTB	45000000	44500000	45800000	45200000	44800000	45100000	Unmodified
P04406	GAPDH	62000000	61800000	62500000	61900000	62200000	62100000	Unmodified
Step 03: VSN Normalization & MinProb Imputation
# R Production Script: VSN Normalization, MinProb Imputation & Limma Differential Abundance
library(DEP)
library(dplyr)
library(SummarizedExperiment)

# 1. Load DIA-NN Protein Group Matrix & filter reverse decoys/contaminants
pg_raw <- read.delim("diann_report.pg_matrix.tsv", stringsAsFactors = FALSE, check.names = FALSE)
pg_clean <- pg_raw %>%
  filter(!grepl("cRAP_|CON__|REV__", Protein.Group)) %>%
  make_unique("Genes", "Protein.Group", delim = ";")

# 2. Experimental design table
exp_design <- data.frame(
  label = c("ctrl_01", "ctrl_02", "ctrl_03", "treat_01", "treat_02", "treat_03"),
  condition = c("Control", "Control", "Control", "Treated", "Treated", "Treated"),
  replicate = c(1, 2, 3, 1, 2, 3)
)

# 3. Construct SummarizedExperiment & filter missing values
sample_cols <- which(colnames(pg_clean) %in% exp_design$label)
se <- make_se(pg_clean, sample_cols, exp_design)
se_filt <- filter_missval(se, thr = 1)

# 4. VSN Normalization & MinProb (q=0.01) left-censored MNAR imputation
se_norm <- normalize_vsn(se_filt)
se_imp <- impute(se_norm, fun = "MinProb", q = 0.01)

# 5. Empirical Bayes testing with limma
se_diff <- test_diff(se_imp, type = "control", control = "Control")
dep_res <- add_rejections(se_diff, alpha = 0.05, lfc = log2(2.0))
write.csv(get_results(dep_res), "proteomics_diff_results.csv", row.names = FALSE)
Step 04: Phosphoproteomics & Kinase Activity Inference (KSEAapp)
# R Production Script: Kinase-Substrate Enrichment Analysis (KSEA)
library(KSEAapp)

# Input format: Protein, Gene, Peptide, Residue.Both (e.g. "S473"), p, FC
px_data <- read.csv("phospho_class1_sites_limma.csv")

# Infer upstream kinase z-scores using PhosphoSitePlus + NetworKIN
KSEA.Complete(
  KSData = KSData,
  PX = px_data,
  NetworKIN = TRUE,
  NetworKIN.cutoff = 5,
  m.cutoff = 5,
  p.cutoff = 0.05
)

🧪 4. Untargeted Metabolomics: XCMS, MZmine 3 & GNPS

Small Molecules • OPLS-DA VIP • Lipids

Metabolomics profiles the downstream metabolic flux resulting from genomic, transcriptomic, and environmental interactions. High-resolution liquid chromatography tandem mass spectrometry (LC-MS/MS) captures thousands of small molecules (<1500 Da), requiring sophisticated peak alignment, signal drift correction across pooled quality controls, and molecular networking.

Standard 5-Stage Architecture

Untargeted LC-MS/MS Metabolomics Pipeline

📦 Toy Dataset: metabolomics_xcms_feature_table.csv (300 Features)
STAGE 1

Centroiding & Peak Picking

Convert vendor files to centroided .mzML via msconvert. Execute XCMS4 CentWave peak detection (ppm = 15, peakwidth = c(5, 30)).

STAGE 2

Alignment & Adduct Deconvolution

Align retention times using Obiwarp, group peak correspondence across sample classes, and deconvolute isotopes/adducts ([M+H]+, [M+Na]+) via CAMERA.

STAGE 3

QC Drift & PQN Scaling

Blank subtraction (Sample/Blank > 3x), pooled QC LOESS drift correction (QC-RLSC), filter features by QC RSD < 20%, and apply Probabilistic Quotient Normalization (PQN) with Pareto scaling.

STAGE 4

Multivariate Chemometrics

Unsupervised PCA (verifying QC cluster tightness) and supervised OPLS-DA with 1,000-permutation testing (R2Y, Q2) in ropls to extract VIP > 1.0 markers.

STAGE 5

MS/MS Matching & Pathways

Structure prediction using SIRIUS 5 + CSI:FingerID, GNPS Feature-Based Molecular Networking (FBMN), and KEGG pathway topological impact enrichment.

Step 01: Peak Detection, RT Alignment & Gap Filling (xcms v4)
# R Production Script: XCMS v4 Peak Picking, Alignment & MS2 Export for GNPS
library(xcms)
library(MsExperiment)
library(Spectra)

# 1. Load metadata & raw files
meta <- read.csv("lcms_injection_sequence.csv")
mse <- readMsExperiment(spectraFiles = meta$file_path, sampleData = meta)

# 2. CentWave Peak Detection
cwp <- CentWaveParam(ppm = 15, peakwidth = c(5, 30), snthresh = 10, prefilter = c(3, 5000), noise = 1000)
xdata <- findChromPeaks(mse, param = cwp)

# 3. Retention Time Alignment (Obiwarp) & Peak Density Correspondence
xdata <- adjustRtime(xdata, param = ObiwarpParam(binSize = 0.6))
pdp <- PeakDensityParam(sampleGroups = sampleData(xdata)$sample_group, minFraction = 0.70, bw = 5, binSize = 0.015)
xdata <- groupChromPeaks(xdata, param = pdp)

# 4. Fill Missing Peaks & Export Feature Matrix
xdata <- fillChromPeaks(xdata, param = ChromPeakAreaParam())
feature_mat <- featureValues(xdata, value = "into", method = "maxint")
feature_def <- as.data.frame(featureDefinitions(xdata))
write.csv(cbind(feature_def[, c("mzmed", "rtmed")], feature_mat), "xcms_raw_feature_table.csv")
Toy Dataset (metabolomics_xcms_feature_table.csv)
Feature_ID,mz,RT_min,Compound,QC_RSD,Ctrl_1,Ctrl_2,Ctrl_3,Dis_1,Dis_2,Dis_3,VIP
FT001,89.0238,1.25,L-Alanine,4.8,48200,47900,49100,51200,50800,51500,0.42
FT002,174.0401,3.42,cis-Aconitate,6.2,124000,121000,126000,38000,36500,39200,2.15
FT003,191.0192,4.81,Citric_Acid,5.1,310000,305000,318000,92000,89000,94500,2.41
FT004,117.0188,2.15,Succinic_Acid,7.4,85000,83000,86500,245000,251000,242000,2.08
FT005,146.0691,5.10,L-Glutamate,8.3,62000,60500,63000,185000,192000,181000,1.89
FT006,203.0531,1.88,D-Glucose,3.9,520000,515000,528000,518000,522000,519000,0.18
Step 02: QC-RLSC Drift & OPLS-DA (pmp + ropls)
library(pmp)
library(ropls)

# 1. Blank Subtraction & Pooled QC LOESS Drift Correction (QC-RLSC)
keep_blk <- rowMeans(feature_mat[, bio_idx], na.rm=TRUE) > (3 * rowMeans(feature_mat[, blank_idx], na.rm=TRUE))
mat_clean <- feature_mat[keep_blk, -blank_idx]
mat_corr  <- QCRSC(df=mat_clean, order=meta_sub$injection_order, batch=rep(1, nrow(meta_sub)), classes=meta_sub$sample_group)
mat_filt  <- filter_peaks_by_rsd(df=mat_corr, classes=meta_sub$sample_group, qc_label="QC", max_rsd=20)

# 2. kNN Imputation & Probabilistic Quotient Normalization (PQN)
mat_imp <- mv_imputation(mat_filt, method="knn")
mat_pqn <- pqn_normalisation(mat_imp, classes=meta_sub$sample_group, qc_label="QC")

# 3. Supervised OPLS-DA (Pareto Scaling, 1000 Permutations)
X_bio <- t(log2(mat_pqn[, bio_mask] + 1))
Y_bio <- factor(meta_sub$sample_group[bio_mask])
opls_mod <- opls(x=X_bio, y=Y_bio, predI=1, orthoI=NA, scaleC="pareto", permI=1000)
vip_scores <- getVipVn(opls_mod)
write.csv(data.frame(Feature=names(vip_scores), VIP=vip_scores), "oplsda_vip_features.csv")
Step 03: In-Silico Structure Annotation (SIRIUS 5 + CSI:FingerID CLI)
# Run SIRIUS + ZODIAC + CSI:FingerID + CANOPUS on exported MS2 .mgf spectra
sirius   --input xcms_ms2_features.mgf   --output ./sirius_project/   --max-mz 850   --cores 16   formula -p orbitrap --ppm-max 5 --candidates 10   zodiac   fingerid --db BIO   canopus   write-summaries --output ./sirius_summaries/

🧬 5. Epigenomics: WGBS/EM-Seq, ATAC-Seq & CUT&Tag

DNA Methylation • Chromatin • Footprinting

Epigenomics reveals how identical genomic sequences produce divergent cellular phenotypes. By profiling 5-methylcytosine (5mC) CpG methylation, Tn5 transposase-accessible chromatin, and histone post-translational modifications, epigenomics uncovers active promoters, distant enhancers, and transcription factor occupancy across development and disease.

Standard 5-Stage Architecture

Epigenomics Pipeline (WGBS/EM-Seq Methylation, ATAC-Seq & CUT&Tag)

📦 Toy Dataset: chr1_mini_bismark.cov.gz & atac_mini_peaks.narrowPeak
STAGE 1

Trimming & Conversion QC

fastp adapter trimming and Bismark 3-letter alignment. Verify C-to-T non-conversion rate on unmethylated lambda phage or chloroplast spike-in controls (>99% conversion efficiency required).

STAGE 2

Context Methylation & DMRs

Extract context-specific methylation (CpG, CHG, CHH) via bismark_methylation_extractor and call Differentially Methylated Regions (DMRs) using DSS beta-binomial models.

STAGE 3

Chromatin Accessibility

ATAC-Seq: Shift Tn5 cut sites (+4 bp / -5 bp via alignmentSieve --ATACshift), filter fragments <100 bp, and call peaks with MACS3 --nomodel --shift -100 --extsize 200.
CUT&Tag: Sparse peak calling with SEACR normalized to IgG control.

STAGE 4

Feature & Motif Footprinting

Annotate peak distribution relative to TSS (±3 kb) using ChIPseeker, generate TSS/TES matrix profiles with deepTools, and scan TF footprints with TOBIAS and HOMER findMotifsGenome.pl.

STAGE 5

Chromatin-to-Expression

Multi-omics integration: Correlate promoter DMR hypomethylation and ATAC-Seq open chromatin peak gains with downstream gene upregulation in paired DESeq2 RNA-Seq datasets.

Track A: WGBS & EM-Seq Methylome Pipeline (Bismark + DSS)
# 1. Prepare Bisulfite/EM-Seq Reference Index & Align Paired-End Reads
bismark_genome_preparation --bowtie2 --parallel 8 ./ref_genome_dir/
bismark --genome ./ref_genome_dir/ -1 R1.fq.gz -2 R2.fq.gz --parallel 4 -p 4 --output_dir ./bismark_aligned/
deduplicate_bismark --bam -p ./bismark_aligned/sample_bismark_bt2_pe.bam

# 2. Extract CpG/CHG/CHH Context Methylation Ratios
bismark_methylation_extractor --paired-end --no_overlap --comprehensive --bedGraph --CX_context   --cytosine_report --genome_folder ./ref_genome_dir/ --parallel 8   sample_bismark_bt2_pe.deduplicated.bam
Track B: ATAC-Seq Tn5 Shift, MACS3 Peaks & TOBIAS Footprinting
# 1. Align with Bowtie2, remove chrM, and filter MAPQ >= 30
bowtie2 --very-sensitive -X 2000 -p 16 -x ref_index -1 atac_R1.fq.gz -2 atac_R2.fq.gz |   samtools view -b -u -q 30 -F 1804 -f 2 - |   samtools idxstats - | cut -f 1 | grep -v -E 'chrM|chrPt|Mt|Pt' |   xargs samtools view -b raw.bam > atac_nuclear_filtered.bam

# 2. Shift Reads for Tn5 Cut-Site (+4 bp / -5 bp) & Call Peaks with MACS3
alignmentSieve --numberOfProcessors 16 --ATACshift --maxFragmentLength 100 --bam dedup.bam -o atac_NFR_shifted.bam
macs3 callpeak -t atac_NFR_shifted.bam -f BAM -g 2.7e9 -n sample_atac --nomodel --shift -100 --extsize 200 --keep-dup all -q 0.01

# 3. Bias-Corrected Transcription Factor Footprinting with TOBIAS
TOBIAS ATACorrect --bam atac_NFR_shifted.bam --genome ref.fa --peaks consensus_peaks.bed --outdir tobias_out --cores 16
TOBIAS ScoreBigwig --signal tobias_out/atac_NFR_shifted_corrected.bw --regions consensus_peaks.bed --output footprints.bw --cores 16
TOBIAS BINDetect --motifs JASPAR_motifs.meme --signals footprints.bw --genome ref.fa --peaks consensus_peaks.bed --outdir bindetect_out --cores 16
Track C: CUT&Tag E. coli Spike-In Scaling & SEACR Sparse Peak Calling
# 1. Scale fragments by E. coli spike-in factor (10,000 / ecoli_reads)
SCALE_FACTOR=$(awk -v ecoli_reads=12500 'BEGIN {print 10000 / ecoli_reads}')
bedtools bamtobed -bedpe -i cutandtag_namesorted.bam | awk '$1==$4 && $6-$2 < 700 {print $1"\t"$2"\t"$6}' | sort -k1,1 -k2,2n > fragments.bed
bedtools genomecov -bg -scale "$SCALE_FACTOR" -i fragments.bed -g ref.chrom.sizes > sample_norm.bedgraph

# 2. Call Stringent Enriched Domains Against IgG Control with SEACR
bash SEACR_1.3.sh sample_norm.bedgraph igg_control_norm.bedgraph non stringent sample_cutandtag_seacr
Toy Dataset (atac_mini_peaks.narrowPeak)
chr1	1002500	1003100	ATAC_Peak_001	450	.	8.42	12.5	9.8	320
chr1	1245000	1245800	ATAC_Peak_002	890	.	15.10	24.8	18.2	410
chr2	3205000	3205900	ATAC_Peak_003	320	.	5.80	8.1	6.4	510
chr3	8420000	8420700	ATAC_Peak_004	920	.	18.25	32.4	26.1	390
chr7	5515000	5516200	ATAC_Peak_005	1100	.	22.40	45.1	38.5	620
chr11	65280000	65280800	ATAC_Peak_006	780	.	12.90	19.5	15.4	400
Executable R ChIPseeker & DSS Recipe
library(ChIPseeker)
library(TxDb.Hsapiens.UCSC.hg38.knownGene)
txdb <- TxDb.Hsapiens.UCSC.hg38.knownGene

# 1. Load atac_mini_peaks.narrowPeak & annotate relative to TSS (+/- 3kb)
peaks <- readPeakFile("atac_mini_peaks.narrowPeak")
peakAnno <- annotatePeak(peaks, tssRegion=c(-3000, 3000), TxDb=txdb)
print(as.data.frame(peakAnno)[, c("seqnames", "start", "end", "annotation", "distanceToTSS")])

# 2. Beta-Binomial DMR Calling with DSS
library(DSS)
# dml_test <- DMLtest(BSobj, group1 = c("C1", "C2"), group2 = c("T1", "T2"), smoothing = TRUE)
# dmrs <- callDMR(dml_test, delta = 0.20, p.threshold = 1e-4)

🌱 6. Plant, Polyploid & Non-Model Genomics: Pangenomes, TEs & Crop GWAS

Wheat • EDTA • SubPhaser • Minigraph-Cactus

Agricultural crops and wild non-model plants represent the frontier of computational biology complexity. Species like allohexaploid bread wheat (Triticum aestivum, 16 Gb), polyploid sugarcane (10 Gb), and octoploid strawberry possess multi-subgenome architectures, extreme repeat densities (>80% retrotransposons), and rampant homoeologous exchange that break standard mammalian analysis pipelines.

🧬

Polyploid Phasing & Subgenomes

Resolve subgenome assemblies (A, B, D) without ancestral references using SubPhaser k-mer enrichment, PacBio HiFi string graphs in Hifiasm, and MCScan collinear synteny mapping.

📦

EDTA De Novo TE Annotation

Structure-based identification of Ty1/Copia, Ty3/Gypsy, Helitrons, and TIR transposons using the EDTA pipeline, with LTR Assembly Index (LAI) validation to certify telomere-to-telomere continuity.

🌾

Crop Graph Pan-Genomics & GWAS

Capture dispensable crop resistance genes with Minigraph-Cactus variation graphs, and map complex quantitative traits with GEMMA mixed models accounting for breeding population structure.

Full Plant Track (13 Chapters) →
SYSTEMS BIOLOGY FUSION

🌐 7. Multi-Omics Data Integration & Machine Learning

Single-omics analyses only capture isolated slices of biological reality. Modern precision medicine increasingly relies on Multi-Omics Data Fusion—combining genomics (germline/somatic mutations), transcriptomics (expression), proteomics, and metabolomics into integrated statistical models.

Multi-Omics Factor Analysis & Data Integration Matrix factorization workflow for Multi-Omics Factor Analysis (MOFA+) combining DNA methylation, RNA expression, proteomics, and metabolomics into shared latent factors. Multi-Omics Factor Analysis (MOFA+) Integration Framework Y₁: DNA Methylation Y₂: mRNA Expression Y₃: Protein Abundance Y₄: Metabolite Levels Heterogeneous Views ≈ Factors (Z) Latent Space × W₁: Methyl Weights W₂: RNA Weights W₃: Protein Weights W₄: Metabolite Weights Downstream Biological Insights: • Patient Subtype Stratification & Survival Risk • Disentangled Molecular Drivers Across Modalities • Imputation of Missing Omics Assays • Single-Cell Multi-Modal CITE-Seq & Multiome Integration MOFA+ • CITE-Seq • Seurat WNN • mixOmics • Graph Neural Networks
Figure 1.7: Multi-Omics Factor Analysis Integration Architecture — Unsupervised Bayesian matrix decomposition combining orthogonal molecular layers into latent factors for biomarker discovery and clinical outcome prediction.

Unsupervised Matrix Factorization (MOFA+)

Multi-Omics Factor Analysis identifies latent dimensions of variation that explain shared vs. assay-specific biological variance across heterogeneous sample cohorts.

Single-Cell Multi-Modal Assays

Assaying multiple molecular layers simultaneously from the exact same single cell: CITE-seq (RNA + cell-surface antibodies), 10x Multiome (RNA + ATAC accessibility).

Network Biology & Graph Neural Networks

Overlaying multi-omics signatures onto biological knowledge graphs (STRING protein-protein interactions, KEGG metabolic reactions) to discover robust clinical biomarkers.

📋 Master Omics Disciplines Comparison Matrix

Quick Reference
Omics DisciplineTarget MoleculePrimary TechnologyCore Data FormatsStandard Software ToolsGlobal Public Repository
GenomicsNuclear / Mt DNAIllumina, PacBio HiFi, ONTFASTQ, BAM, VCFBWA-MEM2, GATK4, DeepVariantNCBI SRA, ENA
TranscriptomicsmRNA, lncRNA, miRNARNA-Seq, 10x Chromium, VisiumFASTQ, Counts, MTXSTAR, Salmon, DESeq2, SeuratNCBI GEO, ArrayExpress
ProteomicsProteins, Peptides, PTMsLC-MS/MS, Cryo-EM, X-rayRAW, mzML, PDBMaxQuant, DIA-NN, AlphaFold 3PRIDE, ProteomeXchange, PDB
MetabolomicsMetabolites (<1.5 kDa)LC-MS, GC-MS, NMRmzML, netCDF, Peak tablesXCMS, MetaboAnalyst, GNPSMetaboLights, Metabolomics Workbench
Epigenomics5mC DNA, Histones, Open ChromatinWGBS, ATAC-seq, ChIP-seqBAM, BigWig, narrowPeakMACS3, Bismark, chromHMMENCODE Portal, GEO
MetagenomicsMicrobial Community DNA16S Amplicon, Shotgun WMSFASTQ, BIOM, FASTA (MAGs)DADA2, QIIME 2, Kraken 2, CheckMMG-RAST, NCBI SRA, ENA