quarTeT: Telomere-to-telomere Toolkit

This page is mainly same as github readme.

However, this page updated not as frequently as on github.


quarTeT is a collection of tools for T2T genome assembly and basic analysis in automatic workflow.

Task include:

Getting Started

Dependencies

  • Python3 (>3.6, tested on 3.7.4 and 3.9.12)
  • Minimap2 (tested on 2.24-r1122 and 2.24-r1155-dirty)
  • MUMmer4 (tested on 4.0.0rc1)
  • trf (tested on 4.09)
  • CD-hit (tested on 4.6 and 4.8.1)
  • BLAST+ (tested on 2.8.1 and 2.11.0)
  • tidk (tested on 0.2.1 and 0.2.31)
  • gnuplot (tested on 4.6 patchlevel 2 and 6)
  • R (>3.5.0, tested on 3.6.0 and 4.2.2)
  • RIdeogram (tested on 0.2.2)

Installation

quarTeT do not require installation.
  1. Download quarTeT
  2. Extract files by tar -xf {path}/quartet.tar.gz
  3. Run python3 {path}/quartet.py to start.

Usage

quarTeT: Telomere-to-telomere Toolkit


Usage: python3 quartet.py <module> <parameters>

Modules:

AssemblyMapper am Assemble draft genome.
GapFiller gf Fill gaps in draft genome.
TeloExplorer te Identify telomeres.
CentroMiner cm Identify centromere candidates.

Use <module> -h for module usage.

AssemblyMapper

AssemblyMapper is a reference-guided assemble tool.

A phased contig-level assembly and a close-related reference genome are required as input, both in fasta format.

Note that contigs should be phased.

It's recommended to obtain such an assembly using hifiasm .

You can convert {prefix}.bp.hap1.p_ctg.gfa and {prefix}.bp.hap2.p_ctg.gfa generated by hifiasm to FASTA format as input, separately.

Usage: python3 quartet.py AssemblyMapper <parameters>

-h, --help show this help message and exit
-r REFERENCE_GENOME (*Required) Reference genome file, FASTA format.
-q CONTIGS (*Required) phased contigs file, FASTA format.
-c MIN_CONTIG_LENGTH Contigs shorter than INT (bp) will be removed, default: 50000
-l MIN_ALIGNMENT_LENGTH The min alignment length to be select (bp), default: 10000
-i MIN_ALIGNMENT_IDENTITY The min alignment identity to be select (%), default: 90
-p PREFIX The prefix used on generated files, default: quarTeT
-t THREADS Use number of threads, default: 1
-a {minimap2,mummer} Specify alignment program (support minimap2 and mummer), default: minimap2
--plot Plot a colinearity graph for draft genome to reference alignments. (will cost more time)
--overwrite Overwrite existing alignment file instead of reuse.
--minimapoption MINIMAPOPTION Pass additional parameters to minimap2 program, default: -x asm5
--nucmeroption NUCMEROPTION Pass additional parameters to nucmer program.
--deltafilteroption DELTAFILTEROPTION Pass additional parameters to delta-filter program.

Output files should be as follow:

{prefix}.draftgenome.fasta The pseudo-chromosome-level assembly, fasta format.
{prefix}.draftgenome.agp The structure of this assembly, AGP format.
{prefix}.draftgenome.stat The statistic of this assembly, including total size and each chromosome's size, GC content, gap count and locations.
{prefix}.draftgenome.png The figure draws relative length of chromosomes and gap locations for assembly.
{prefix}.contig.mapinfo The statistic of input contigs, including total mapped and discarded size, and each contig's destination.
{prefix}.contig_map_ref.png The alignment colinearity graph between contigs and reference genome.
{prefix}.draftgenome_map_ref.png The alignment colinearity graph between this assembly genome and reference genome. Only available with --plot.

GapFiller

GapFiller is a long-reads based gapfilling tool.

A gap-tied genome and corresponding long-reads are required as input, both in fasta format.

If possible, using long-reads assembled and polished contigs instead of reads may improve the quality.

Usage: python3 quartet.py GapFiller <parameters>

-h, --help show this help message and exit
-d DRAFT_GENOME (*Required) Draft genome file to be filled, FASTA format.
-g GAPCLOSER_CONTIG [GAPCLOSER_CONTIG ...] (*Required) All contigs files (accept multiple file) used to fill gaps, FASTA format.
-f FLANKING_LEN The flanking seq length of gap used to anchor (bp), default: 5000
-l MIN_ALIGNMENT_LENGTH The min alignment length to be select (bp), default: 1000
-i MIN_ALIGNMENT_IDENTITY The min alignment identity to be select (%), default: 40
-m MAX_FILLING_LEN The max sequence length acceptable to fill any gaps, default: 1000000
-p PREFIX The prefix used on generated files, default: quarTeT
-t THREADS Use number of threads, default: 1
--overwrite Overwrite existing alignment file instead of reuse.
--minimapoption MINIMAPOPTION Pass additional parameters to minimap2 program, default: -x asm5

Output files should be as follow:

{prefix}.genome.filled.fasta The gap-filled genome, fasta format.
{prefix}.genome.filled.detail Detailed information for each gap, including gap closed and remains, total filled size and closer's ID, range, etc.
{prefix}.genome.filled.stat The statistic of filled genome, including total size and each chromosome's size, GC content, gap count and locations.
{prefix}.genome.filled.png The figure draws relative length of chromosomes and gap locations for assembly.

TeloExplorer

TeloExplorer is a telomere identification tool.

A genome file in fasta format is required as input.

Usage: python3 quartet.py TeloExplorer <parameters>

-h, --help show this help message and exit
-i GENOME (*Required) Genome file to be identified, FASTA format.
-c {plant,animal,other} Specify clade of this genome. Plant will search TTTAGGG, animal will search TTAGGG, other will use tidk explore's suggestion, default: other
-m MIN_REPEAT_TIMES The min repeat times to be reported, default: 100
-p PREFIX The prefix used on generated files, default: quarTeT

Output files should be as follow:

{prefix}.telo.info The statistic of telomere, including monomer, repeat times on both end of each chromosome.
{prefix}.telo.png The figure draws telomere location, alongside relative length of chromosomes and gap locations for assembly.

CentroMiner

CentroMiner is a centromere prediction tool.

A genome file in fasta format is required as input.

Optionally, an addition input of TE annotation (or just LTR annotation) in gff3 format can improve the performance.

It's recommended to obtain TE annotation using EDTA.

{genome file}.mod.EDTA.TEanno.gff3 generated by EDTA can directly feed CentroMiner, unless you have sequence ID longer than 15 characters.

Note that the sequence ID in first column should be consistent with in genome. Some tools may change sequence ID if ID is too long.

The sequence ontology in the third column should include "LTR" to be recognized.

Usage: python3 quartet.py CentroMiner <parameters>

-h, --help show this help message and exit
-i GENOME_FASTA (*Required) Genome file, FASTA format.
--TE TE TE annotation file, gff3 format.
-n MIN_PERIOD Min period to be consider as centromere repeat monomer. Default: 100
-m MAX_PERIOD Max period to be consider as centromere repeat monomer. Default: 200
-s CLUSTER_IDENTITY Min identity between TR monomers to be clustered (Cannot be smaller than 0.8). Default: 0.8
-d CLUSTER_MAX_DELTA Max period delta for TR monomers in a cluster. Default: 10
-e EVALUE E-value threholds in blast. Default: 0.00001
-g MAX_GAP Max allowed gap size between two tandem repeats to be considered as in one tandem repeat region. Default: 50000
-l MIN_LENGTH Min size of tandem repeat region to be selected as candidate. Default: 100000
-t THREADS Limit number of using threads, default: 1
-p PREFIX Prefix used by generated files. Default: quarTeT
--trf [TRF_PARAMETER ...] Change TRF parameters: <match> <mismatch> <delta> <PM> <PI> <minscore> Default: 2 7 7 80 10 50
--overwrite Overwrite existing trf dat file instead of reuse.

Output files should be as follow:

{prefix}.best.candidate The best centromere candidate on each chromosome, and corresponding monomers.
{prefix}.centro.png The figure draws best centromere candidate location, alongside relative length of chromosomes and gap locations for assembly.
candidate/ The folder of all centromere candidates. Check here if the best candidate doesn't look well.
TRfasta/ The folder of all tandem repeat monomers identified by trf and cluster result on each chromosome.
TRgff3/ The folder of all tandem repeat hit by BLAST on each chromosome, in gff3 format.