In [1]:
from collections import defaultdict, OrderedDict
import warnings
import logging
import gffutils
import pybedtools
import pandas as pd
import copy
import re
from gffutils.pybedtools_integration import tsses

logging.basicConfig(level=logging.INFO)

In [2]:
gtf = '/home/cmb-panasas2/skchoudh/genomes/rn6/annotation/Rattus_norvegicus.Rnor_6.0.91.gtf'
gtf_db = '/home/cmb-panasas2/skchoudh/genomes/rn6/annotation/Rattus_norvegicus.Rnor_6.0.91.gtf.db'
prefix = '/home/cmb-panasas2/skchoudh/genomes/rn6/annotation/Rattus_norvegicus.Rnor_6.0.91.gffutils'
chrsizes = '/home/cmb-panasas2/skchoudh/genomes/rn6/fasta/Rattus_norvegicus.Rnor_6.0.dna.toplevel.sizes'

In [3]:
db = gffutils.create_db(gtf, dbfn=gtf_db, disable_infer_genes=True, disable_infer_transcripts=True, merge_strategy='merge', force=True)
def create_gene_dict(db):
    '''
    Store each feature line db.all_features() as a dict of dicts
    '''
    gene_dict = defaultdict(lambda: defaultdict(lambda: defaultdict(list)))
    for line_no, feature in enumerate(db.all_features()):
        gene_ids = feature.attributes['gene_id']
        feature_type = feature.featuretype
        if feature_type == 'gene':
            if len(gene_ids)!=1:
                logging.warning('Found multiple gene_ids on line {} in gtf'.format(line_no))
                break
            else:
                gene_id = gene_ids[0]
                gene_dict[gene_id]['gene'] = feature
        else:
            transcript_ids = feature.attributes['transcript_id']

            for gene_id in gene_ids:
                for transcript_id in transcript_ids:
                    gene_dict[gene_id][transcript_id][feature_type].append(feature)
    return gene_dict

In [4]:
db = gffutils.FeatureDB(gtf_db, keep_order=True)
gene_dict = create_gene_dict(db)

In [5]:
for x in db.featuretypes():
    print(x)


CDS
Selenocysteine
exon
five_prime_utr
gene
start_codon
stop_codon
three_prime_utr
transcript

In [6]:
def get_gene_list(gene_dict):
    return list(set(gene_dict.keys()))

def get_UTR_regions(gene_dict, gene_id, transcript, cds):
    if len(cds)==0:
        return [], []
    utr5_regions = []
    utr3_regions = []
    utrs = gene_dict[gene_id][transcript]['UTR']
    first_cds = cds[0]
    last_cds = cds[-1]
    for utr in utrs:
        ## Push all cds at once
        ## Sort later to remove duplicates
        strand = utr.strand
        if strand == '+':
            if utr.stop < first_cds.start:
                utr.feature_type = 'five_prime_UTR'
                utr5_regions.append(utr)
            elif utr.start > last_cds.stop:
                utr.feature_type = 'three_prime_UTR'
                utr3_regions.append(utr)
            else:
                raise RuntimeError('Error with cds')
        elif strand == '-':
            if utr.stop < first_cds.start:
                utr.feature_type = 'three_prime_UTR'
                utr3_regions.append(utr)
            elif utr.start > last_cds.stop:
                utr.feature_type = 'five_prime_UTR'
                utr5_regions.append(utr)                
            else:
                raise RuntimeError('Error with cds')    
    return utr5_regions, utr3_regions
    
def create_bed(regions, bedtype='0'):
    '''Create bed from list of regions
    bedtype: 0 or 1
        0-Based or 1-based coordinate of the BED
    '''
    bedstr = ''
    for region in regions:
        assert len(region.attributes['gene_id']) == 1
        ## GTF start is 1-based, so shift by one while writing 
        ## to 0-based BED format
        if bedtype == '0':
            start = region.start - 1
        else:
            start = region.start
        bedstr += '{}\t{}\t{}\t{}\t{}\t{}\n'.format(region.chrom,
                                             start,
                                             region.stop,
                                             re.sub('\.\d+', '', region.attributes['gene_id'][0]),
                                             '.',
                                             region.strand)
    # Remove duplicates
    bedstr = '\n'.join(list(OrderedDict.fromkeys(bedstr.split('\n'))))
    return bedstr

def rename_regions(regions, gene_id):
    regions = list(regions)
    if len(regions) == 0:
        return []
    for region in regions:
        region.attributes['gene_id'] = gene_id
    return regions

def merge_regions(db, regions):
    if len(regions) == 0:
        return []
    merged = db.merge(sorted(list(regions), key=lambda x: x.start))
    return merged

def merge_regions_nostrand(db, regions):
    if len(regions) == 0:
        return []
    merged = db.merge(sorted(list(regions), key=lambda x: x.start), ignore_strand=True)
    return merged

In [7]:
utr5_bed = ''
utr3_bed = ''



gene_bed = ''
exon_bed = ''
intron_bed = ''
start_codon_bed = ''
stop_codon_bed = ''
cds_bed = ''

gene_list = []

for gene_id in get_gene_list(gene_dict):
    gene_list.append(gene_dict[gene_id]['gene'])
    
    utr5_regions, utr3_regions = [], []
    exon_regions, intron_regions = [], []
    star_codon_regions, stop_codon_regions = [], []
    cds_regions = []
    
    for feature in gene_dict[gene_id].keys():
        if feature == 'gene':
            continue
        cds = list(gene_dict[gene_id][feature]['CDS'])
        exons = list(gene_dict[gene_id][feature]['exon'])
        merged_exons = merge_regions(db, exons)
        introns = db.interfeatures(merged_exons)
        utr5_region = list(gene_dict[gene_id][feature]['five_prime_utr'])
        utr3_region = list(gene_dict[gene_id][feature]['three_prime_utr'])
        utr5_regions += utr5_region
        utr3_regions += utr3_region
        exon_regions += exons
        intron_regions += introns
        cds_regions += cds
        
    merged_utr5 = merge_regions(db, utr5_regions)
    renamed_utr5 = rename_regions(merged_utr5, gene_id)
    
    merged_utr3 = merge_regions(db, utr3_regions)
    renamed_utr3 = rename_regions(merged_utr3, gene_id)
    
    merged_exons = merge_regions(db, exon_regions)
    renamed_exons = rename_regions(merged_exons, gene_id)
    
    merged_introns = merge_regions(db, intron_regions)
    renamed_introns = rename_regions(merged_introns, gene_id)
    
    merged_cds = merge_regions(db, cds_regions)
    renamed_cds = rename_regions(merged_cds, gene_id)
    
    utr3_bed += create_bed(renamed_utr3)
    utr5_bed += create_bed(renamed_utr5)
    exon_bed += create_bed(renamed_exons)
    intron_bed += create_bed(renamed_introns)
    cds_bed += create_bed(renamed_cds)
    
    
gene_bed = create_bed(gene_list)
gene_bedtool = pybedtools.BedTool(gene_bed, from_string=True)
utr5_bedtool = pybedtools.BedTool(utr5_bed, from_string=True)
utr3_bedtool = pybedtools.BedTool(utr3_bed, from_string=True)
exon_bedtool = pybedtools.BedTool(exon_bed, from_string=True)
intron_bedtool = pybedtools.BedTool(intron_bed, from_string=True)
cds_bedtool = pybedtools.BedTool(cds_bed, from_string=True)

gene_bedtool.remove_invalid().sort().saveas('{}.genes.bed'.format(prefix))
utr5_bedtool.remove_invalid().sort().saveas('{}.UTR5.bed'.format(prefix))
utr3_bedtool.remove_invalid().sort().saveas('{}.UTR3.bed'.format(prefix))
exon_bedtool.remove_invalid().sort().saveas('{}.exon.bed'.format(prefix))
intron_bedtool.remove_invalid().sort().saveas('{}.intron.bed'.format(prefix))
cds_bedtool.remove_invalid().sort().saveas('{}.cds.bed'.format(prefix))


Out[7]:
<BedTool(/home/cmb-panasas2/skchoudh/genomes/rn6/annotation/Rattus_norvegicus.Rnor_6.0.91.gffutils.cds.bed)>

In [8]:
utr5_region_bed = ''
utr3_region_bed = ''


for gene_id in get_gene_list(gene_dict):
    utr5_regions = []
    utr3_regions = []
    for utr5_region in db.children(gene_id, featuretype='five_prime_utr'):
        utr5_regions.append(utr5_region)
    for utr3_region in db.children(gene_id, featuretype='three_prime_utr'):
        utr3_regions.append(utr3_region)
    merged_utr5_regions = merge_regions(db, utr5_regions)
    renamed_utr5_regions = rename_regions(merged_utr5_regions, gene_id)
    merged_utr3_regions = merge_regions(db, utr3_regions)
    renamed_utr3_regions = rename_regions(merged_utr3_regions, gene_id)
    
    utr5_region_bed += create_bed(renamed_utr5_regions)    
    utr3_region_bed += create_bed(renamed_utr3_regions)


    
utr5_region_bedtool = pybedtools.BedTool(utr5_region_bed, from_string=True)
utr3_region_bedtool = pybedtools.BedTool(utr3_region_bed, from_string=True)

In [9]:
utr5_region_bedtool.remove_invalid().sort().saveas('{}.utr5_region.bed'.format(prefix))
utr3_region_bedtool.remove_invalid().sort().saveas('{}.utr3_region.bed'.format(prefix))


Out[9]:
<BedTool(/home/cmb-panasas2/skchoudh/genomes/rn6/annotation/Rattus_norvegicus.Rnor_6.0.91.gffutils.utr3_region.bed)>

In [10]:
'{}.utr5_region.bed'.format(prefix)


Out[10]:
'/home/cmb-panasas2/skchoudh/genomes/rn6/annotation/Rattus_norvegicus.Rnor_6.0.91.gffutils.utr5_region.bed'

In [11]:
!bedSort /home/cmb-panasas2/skchoudh/genomes/rn6/annotation/Rattus_norvegicus.Rnor_6.0.91.gffutils.utr5_region.bed /home/cmb-panasas2/skchoudh/genomes/rn6/annotation/Rattus_norvegicus.Rnor_6.0.91.gffutils.utr5_region.bed

In [12]:
!bedSort /home/cmb-panasas2/skchoudh/genomes/rn6/annotation/Rattus_norvegicus.Rnor_6.0.91.gffutils.utr3_region.bed /home/cmb-panasas2/skchoudh/genomes/rn6/annotation/Rattus_norvegicus.Rnor_6.0.91.gffutils.utr3_region.bed

In [13]:
tRNA_sites = []
tRNA_bed = ''
for gene_id in get_gene_list(gene_dict):
    for transcript in db.children(gene_id, featuretype='transcript'):
        if 'tRNA' in transcript.attributes['gene_biotype'] or 'Mt_tRNA' in transcript.attributes['transcript_biotype']:
            tRNA_sites.append(transcript)
    #merged_tRNA_sites = merge_regions_nostrand(db, tRNA_sites)
    #renamed_tRNA_sites = rename_regions(merged_tRNA_sites, gene_id)
    tRNA_bed += create_bed(tRNA_sites)

tRNA_bed = '\n'.join(list(OrderedDict.fromkeys(tRNA_bed.split('\n'))))
tRNA_sites_bedtool = pybedtools.BedTool(tRNA_bed, from_string=True)
tRNA_sites_bedtool.remove_invalid().sort().saveas('{}.tRNA_sites.bed'.format(prefix))


Out[13]:
<BedTool(/home/cmb-panasas2/skchoudh/genomes/rn6/annotation/Rattus_norvegicus.Rnor_6.0.91.gffutils.tRNA_sites.bed)>

In [14]:
tRNA_sites_bedtool.to_dataframe()


Out[14]:
chrom start end name score strand
0 MT 1025 1093 ENSRNOG00000029171 . +
1 MT 3760 3831 ENSRNOG00000033545 . -
2 MT 5009 5078 ENSRNOG00000033932 . -
3 MT 9799 9867 ENSRNOG00000032320 . +
4 MT 11664 11735 ENSRNOG00000031667 . +
5 MT 15279 15346 ENSRNOG00000030339 . +
6 MT 3834 3903 ENSRNOG00000032274 . +
7 MT 5255 5321 ENSRNOG00000029954 . -
8 MT 6864 6933 ENSRNOG00000032882 . -
9 MT 6936 7004 ENSRNOG00000031685 . +
10 MT 5080 5152 ENSRNOG00000032609 . -
11 MT 2664 2739 ENSRNOG00000032112 . +
12 MT 3694 3763 ENSRNOG00000029301 . +
13 MT 9382 9450 ENSRNOG00000029389 . +
14 MT 11605 11665 ENSRNOG00000032578 . +
15 MT 15347 15415 ENSRNOG00000029145 . -
16 MT 7692 7756 ENSRNOG00000029070 . +
17 MT 5184 5252 ENSRNOG00000031333 . -
18 MT 0 67 ENSRNOG00000031780 . +
19 MT 14061 14130 ENSRNOG00000032997 . -
20 MT 4942 5008 ENSRNOG00000029677 . +
21 MT 11537 11605 ENSRNOG00000033957 . +

In [15]:
rRNA_sites = []
rRNA_bed = ''
for gene_id in get_gene_list(gene_dict):
    for transcript in db.children(gene_id, featuretype='transcript'):
        if 'rRNA' in transcript.attributes['gene_biotype']:
            rRNA_sites.append(transcript)
    #renamed_rRNA_sites = rename_regions(rRNA_sites, gene_id)
    rRNA_bed += create_bed(rRNA_sites)
rRNA_bed = '\n'.join(list(OrderedDict.fromkeys(rRNA_bed.split('\n'))))
rRNA_sites_bedtool = pybedtools.BedTool(rRNA_bed, from_string=True)
rRNA_sites_bedtool.remove_invalid().sort().saveas('{}.rRNA_sites.bed'.format(prefix))


Out[15]:
<BedTool(/home/cmb-panasas2/skchoudh/genomes/rn6/annotation/Rattus_norvegicus.Rnor_6.0.91.gffutils.rRNA_sites.bed)>

In [16]:
rRNA_sites_bedtool.to_dataframe()


Out[16]:
chrom start end name score strand
0 1 71911839 71911956 ENSRNOG00000035686 . +
1 X 40233279 40233412 ENSRNOG00000044409 . +
2 X 22375179 22375302 ENSRNOG00000057146 . +
3 2 128826107 128826252 ENSRNOG00000055218 . +
4 13 51976772 51976852 ENSRNOG00000044610 . -
5 5 91134984 91135137 ENSRNOG00000056172 . +
6 6 72181426 72181547 ENSRNOG00000035437 . -
7 12 9651828 9651948 ENSRNOG00000036163 . +
8 9 96705076 96705194 ENSRNOG00000044330 . +
9 7 32471289 32471411 ENSRNOG00000044338 . -
10 1 262963568 262963688 ENSRNOG00000048483 . -
11 X 9541226 9541333 ENSRNOG00000049449 . -
12 12 42025660 42025779 ENSRNOG00000035103 . -
13 4 153099267 153099386 ENSRNOG00000036453 . +
14 2 161553281 161553434 ENSRNOG00000052601 . +
15 17 25470866 25470995 ENSRNOG00000044699 . -
16 18 64976334 64976448 ENSRNOG00000044715 . -
17 5 25704483 25704585 ENSRNOG00000044719 . +
18 17 12278480 12278592 ENSRNOG00000042007 . +
19 3 114919676 114919766 ENSRNOG00000050064 . -
20 14 9278880 9278990 ENSRNOG00000045148 . -
21 KL568337.1 50361 50514 ENSRNOG00000061546 . -
22 3 66007446 66007559 ENSRNOG00000034920 . +
23 14 60192138 60192257 ENSRNOG00000040878 . -
24 KL568337.1 48815 48968 ENSRNOG00000054432 . -
25 X 106830662 106830781 ENSRNOG00000035238 . +
26 X 92069988 92070113 ENSRNOG00000041845 . -
27 1 255816887 255816993 ENSRNOG00000044566 . +
28 18 11640200 11640300 ENSRNOG00000041864 . +
29 7 29252547 29252666 ENSRNOG00000036071 . -
... ... ... ... ... ... ...
299 8 64903583 64903692 ENSRNOG00000044880 . -
300 9 81051936 81052027 ENSRNOG00000044889 . +
301 13 7160200 7160310 ENSRNOG00000043886 . +
302 6 30630901 30631054 ENSRNOG00000058896 . +
303 8 126876672 126876824 ENSRNOG00000058530 . +
304 16 47464313 47464429 ENSRNOG00000041010 . -
305 16 15660278 15660304 ENSRNOG00000044126 . -
306 20 46580450 46580567 ENSRNOG00000044128 . +
307 4 125508103 125508199 ENSRNOG00000044767 . -
308 13 58460921 58461036 ENSRNOG00000036200 . +
309 13 100451993 100452108 ENSRNOG00000060813 . -
310 10 8469911 8470006 ENSRNOG00000045175 . +
311 3 137613124 137613245 ENSRNOG00000045172 . +
312 16 20205910 20206005 ENSRNOG00000050776 . +
313 11 11978347 11978454 ENSRNOG00000040821 . +
314 8 39495975 39496084 ENSRNOG00000041053 . +
315 11 89141609 89141718 ENSRNOG00000045755 . -
316 6 44933673 44933779 ENSRNOG00000041834 . +
317 9 26776808 26776927 ENSRNOG00000045032 . -
318 2 66694827 66694947 ENSRNOG00000045036 . +
319 1 221520758 221520838 ENSRNOG00000044076 . +
320 6 116965664 116965762 ENSRNOG00000044660 . -
321 9 34271708 34271827 ENSRNOG00000035416 . -
322 12 346961 347106 ENSRNOG00000059668 . -
323 18 59603993 59604115 ENSRNOG00000035926 . -
324 3 159426717 159426836 ENSRNOG00000045650 . +
325 9 15728072 15728184 ENSRNOG00000043884 . -
326 2 161559585 161559738 ENSRNOG00000059464 . +
327 10 78714985 78715086 ENSRNOG00000045070 . +
328 2 230213323 230213440 ENSRNOG00000049473 . +

329 rows × 6 columns


In [17]:
for gene_id in get_gene_list(gene_dict):
    start_codons = []
    stop_codons = []
    for start_codon in db.children(gene_id, featuretype='start_codon'):
        ## 1 -based stop
        ## 0-based start handled while converting to bed
        start_codon.stop = start_codon.start
        start_codons.append(start_codon)
    for stop_codon in db.children(gene_id, featuretype='stop_codon'):
        stop_codon.start = stop_codon.stop
        stop_codon.stop = stop_codon.stop+1
        stop_codons.append(stop_codon)
    merged_start_codons = merge_regions(db, start_codons)
    renamed_start_codons = rename_regions(merged_start_codons, gene_id)
    merged_stop_codons = merge_regions(db, stop_codons)
    renamed_stop_codons = rename_regions(merged_stop_codons, gene_id)
    
    start_codon_bed += create_bed(renamed_start_codons)    
    stop_codon_bed += create_bed(renamed_stop_codons)


    
start_codon_bedtool = pybedtools.BedTool(start_codon_bed, from_string=True)
stop_codon_bedtool = pybedtools.BedTool(stop_codon_bed, from_string=True)
start_codon_bedtool.remove_invalid().sort().saveas('{}.start_codon.bed'.format(prefix))
stop_codon_bedtool.remove_invalid().sort().saveas('{}.stop_codon.bed'.format(prefix))


Out[17]:
<BedTool(/home/cmb-panasas2/skchoudh/genomes/rn6/annotation/Rattus_norvegicus.Rnor_6.0.91.gffutils.stop_codon.bed)>

In [18]:
## TSS
polyA_sites_bed = ''
tss_sites_bed = ''
for gene_id in get_gene_list(gene_dict):
    tss_sites = []
    polyA_sites = []
    for transcript in db.children(gene_id, featuretype='transcript'):
        start_t = copy.deepcopy(transcript)
        stop_t = copy.deepcopy(transcript)
        
        start_t.stop = start_t.start + 1
        
        stop_t.start = stop_t.stop
        
        if transcript.strand == '-':
            start_t, stop_t = stop_t, start_t
        polyA_sites.append(start_t)
        tss_sites.append(stop_t)
    merged_polyA_sites = merge_regions(db, polyA_sites)
    renamed_polyA_sites = rename_regions(merged_polyA_sites, gene_id)    
    merged_tss_sites = merge_regions(db, tss_sites)
    renamed_tss_sites = rename_regions(merged_tss_sites, gene_id)
    polyA_sites_bed += create_bed(renamed_polyA_sites)    
    tss_sites_bed += create_bed(renamed_tss_sites)

polyA_sites_bedtool = pybedtools.BedTool(polyA_sites_bed, from_string=True)
tss_sites_bedtool = pybedtools.BedTool(tss_sites_bed, from_string=True)
polyA_sites_bedtool.remove_invalid().sort().saveas('{}.polyA_sites.bed'.format(prefix))
tss_sites_bedtool.remove_invalid().sort().saveas('{}.tss_sites.bed'.format(prefix))


Out[18]:
<BedTool(/home/cmb-panasas2/skchoudh/genomes/rn6/annotation/Rattus_norvegicus.Rnor_6.0.91.gffutils.tss_sites.bed)>

In [19]:
tss = tsses(db, as_bed6=True)#, merge_overlapping=True)
tss.remove_invalid().sort().saveas('{}.tss_temp.bed'.format(prefix))
promoter = tss.slop(l=1000, r=1000, s=True, g=chrsizes)
promoter.remove_invalid().sort().saveas('{}.promoter.1000.bed'.format(prefix))


Out[19]:
<BedTool(/home/cmb-panasas2/skchoudh/genomes/rn6/annotation/Rattus_norvegicus.Rnor_6.0.91.gffutils.promoter.1000.bed)>

In [20]:
for l in [1000, 2000, 3000, 4000, 5000]:
    promoter = tss.slop(l=l, r=l, s=True, g=chrsizes)
    promoter.remove_invalid().sort().saveas('{}.promoter.{}.bed'.format(prefix, l))

In [ ]: