CROT

gene
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Also known as COT

Summary

CROT (carnitine O-octanoyltransferase, HGNC:2366) is a protein-coding gene on chromosome 7q21.12, encoding Peroxisomal carnitine O-octanoyltransferase (Q9UKG9). Beta-oxidation of fatty acids.

This gene encodes a member of the carnitine/choline acetyltransferase family. The encoded protein converts 4,8-dimethylnonanoyl-CoA to its corresponding carnitine ester. This transesterification occurs in the peroxisome and is necessary for transport of medium- and long- chain acyl-CoA molecules out of the peroxisome to the cytosol and mitochondria. The protein thus plays a role in lipid metabolism and fatty acid beta-oxidation. Alternatively spliced transcript variants have been described.

Source: NCBI Gene 54677 — RefSeq curated summary.

At a glance

  • GWAS associations: 2
  • Clinical variants (ClinVar): 39 total
  • Druggable target: yes
  • MANE Select transcript: NM_021151

Identifiers

Gene identifiers

FieldValue
HGNC IDHGNC:2366
Approved symbolCROT
Namecarnitine O-octanoyltransferase
Location7q21.12
Locus typegene with protein product
StatusApproved
AliasesCOT
Ensembl geneENSG00000005469
Ensembl biotypeprotein_coding
OMIM606090
Entrez54677

Gene structure

Transcript identifiers

Ensembl transcripts: 11 — 8 protein_coding, 3 retained_intron

ENST00000331536, ENST00000412227, ENST00000419147, ENST00000442291, ENST00000469785, ENST00000479014, ENST00000488850, ENST00000881399, ENST00000881400, ENST00000881401, ENST00000947266

RefSeq mRNA: 3 — MANE Select: NM_021151 NM_001143935, NM_001243745, NM_021151

CCDS: CCDS47634, CCDS5604, CCDS59062

Canonical transcript exons

ENST00000331536 — 18 exons

ExonStartEnd
ENSE000007038028739294887393067
ENSE000007038068739273087392823
ENSE000007038108739256687392644
ENSE000007038148739158987391712
ENSE000007038178738241387382543
ENSE000007038198738207487382181
ENSE000007038298737582887375953
ENSE000007038328737563287375725
ENSE000007038358736937687369484
ENSE000007038418736139087361571
ENSE000007038448735920687359330
ENSE000008771438734904887349183
ENSE000010166818734634087346430
ENSE000013186338739852487399794
ENSE000019131798734566487345767
ENSE000034720718738191087381993
ENSE000035262508736172887361852
ENSE000036822678737734987377450

Expression profiles

Bgee: expression breadth ubiquitous, 287 present calls, max score 95.66.

FANTOM5 (CAGE): breadth ubiquitous, TPM avg 6.9320 / max 185.4348, expressed in 1642 samples.

FANTOM5 promoters (4 alternative TSS)

Promoter IDTPM avgSamples expressed
793933.84491526
793941.8295878
793950.8436387
793960.4140192

Top tissues by expression

295 total, by Bgee expression score (0-100, higher = more expressed):

TissueAnatomy IDExpression scoreQuality
esophagus squamous epitheliumUBERON:000692095.66gold quality
cervix squamous epitheliumUBERON:000692295.35gold quality
seminal vesicleUBERON:000099895.33gold quality
jejunal mucosaUBERON:000039995.27gold quality
mucosa of urinary bladderUBERON:000125994.79gold quality
epithelium of esophagusUBERON:000197694.74gold quality
squamous epitheliumUBERON:000691494.73gold quality
upper leg skinUBERON:000426294.22gold quality
duodenumUBERON:000211493.35gold quality
tongue squamous epitheliumUBERON:000691992.88gold quality
palpebral conjunctivaUBERON:000181292.78gold quality
urethraUBERON:000005792.73gold quality
hair follicleUBERON:000207392.52gold quality
gingival epitheliumUBERON:000194992.15gold quality
cervix epitheliumUBERON:000480192.01gold quality
gingivaUBERON:000182891.78gold quality
epithelium of nasopharynxUBERON:000195191.43gold quality
left lobe of thyroid glandUBERON:000112091.36gold quality
right lobe of thyroid glandUBERON:000111991.35gold quality
germinal epithelium of ovaryUBERON:000130491.26gold quality
jejunumUBERON:000211591.26gold quality
choroid plexus epitheliumUBERON:000391191.19gold quality
mammalian vulvaUBERON:000099791.13gold quality
thyroid glandUBERON:000204690.89gold quality
corpus epididymisUBERON:000435990.31gold quality
cauda epididymisUBERON:000436090.19gold quality
oral cavityUBERON:000016790.16gold quality
skin of hipUBERON:000155489.83gold quality
urinary bladderUBERON:000125589.73gold quality
parietal pleuraUBERON:000240089.73gold quality

Single-cell (SCXA)

Detected in 1 experiment(s), a significant marker in 1.

ExperimentMarker?Max mean expression
E-ANND-3no0.00

Regulation

Is transcription factor: no

miRNA regulators (miRDB)

79 targeting CROT, top 30 by miRDB confidence (max_score; target_count = how many genes the miRNA targets in total — lower means more specific):

miRNAMax scoreAvg scoremiRNA target_count
HSA-MIR-6867-5P100.0082.213464
HSA-MIR-6758-5P100.0066.211470
HSA-MIR-6856-5P100.0065.471298
HSA-MIR-33A-5P99.9968.621055
HSA-MIR-33B-5P99.9968.581062
HSA-MIR-513B-5P99.9969.962150
HSA-MIR-569699.9872.364487
HSA-MIR-302E99.9670.742669
HSA-MIR-548AJ-3P99.9673.385345
HSA-MIR-548X-3P99.9673.385345
HSA-MIR-548J-3P99.9472.614881
HSA-MIR-548AE-3P99.9372.664867
HSA-MIR-548AH-3P99.9372.544872
HSA-MIR-548AM-3P99.9372.544872
HSA-MIR-548AQ-3P99.9372.664867
HSA-MIR-7-1-3P99.9171.534384
HSA-MIR-7-2-3P99.9171.404394
HSA-MIR-6809-3P99.9171.453814
HSA-MIR-106A-5P99.9073.942683
HSA-MIR-4753-3P99.9071.033786
HSA-MIR-302A-3P99.8971.231777
HSA-MIR-302B-3P99.8971.231777
HSA-MIR-302C-3P99.8971.201778
HSA-MIR-302D-3P99.8971.251777
HSA-MIR-17-5P99.8973.832665
HSA-MIR-153-5P99.8973.866317
HSA-MIR-106B-5P99.8874.722795
HSA-MIR-20A-5P99.8874.762769
HSA-MIR-526B-3P99.8874.062587
HSA-MIR-20B-5P99.8874.012621

Literature-anchored findings (GeneRIF, showing 6)

  • CROT encodes carnitine octanoyltransferase, an enzyme known from rat studies to act on products of peroxisomal fatty acid oxidation. Medium-chain acylcarnitines are thought to be transported from peroxisomes to mitochondria. (PMID:11001805)
  • Human CPT1A, CPT1B, CPT2, CROT and CRAT are known to encode active carnitine acyltransferases. Earlier pfam annotations refer to the non-existing compound CARNITATE. In 2000 this has been changed to CARNITINE. (PMID:11001805)
  • Selected ‘Tpl2/Cot-YL ribozyme’ efficiently cleaves its target sequence in cis and in trans; furthermore, the ribozyme efficiently cleaves a longer target sequence of 54 nucleotides in trans, as well as the full-length mRNA. (PMID:19054068)
  • These results suggest that CROT activity, by controlling the peroxisomal amount of medium chain acyls, may control the peroxisomal oxidative pathway. (PMID:21619872)
  • CROT (Carnitine O-Octanoyltransferase) Is a Novel Contributing Factor in Vascular Calcification via Promoting Fatty Acid Metabolism and Mitochondrial Dysfunction. (PMID:33356393)
  • Carnitine octanoyltransferase is important for the assimilation of exogenous acetyl-L-carnitine into acetyl-CoA in mammalian cells. (PMID:36587768)

Cross-species orthologs

6 orthologs

OrganismSymbolGene ID
danio_reriocrotENSDARG00000040352
mus_musculusCrotENSMUSG00000003623
rattus_norvegicusCrotENSRNOG00000006779
drosophila_melanogasterCROTFBGN0039543
caenorhabditis_elegansWBGENE00009622
caenorhabditis_elegansWBGENE00011850

Paralogs (6): CHAT (ENSG00000070748), CRAT (ENSG00000095321), CPT1A (ENSG00000110090), CPT2 (ENSG00000157184), CPT1C (ENSG00000169169), CPT1B (ENSG00000205560)

Protein

Protein identifiers

Peroxisomal carnitine O-octanoyltransferaseQ9UKG9 (reviewed: Q9UKG9)

All UniProt accessions (2): Q9UKG9, C9J3D7

UniProt curated annotations — full annotation on UniProt →

Function. Beta-oxidation of fatty acids. The highest activity concerns the C6 to C10 chain length substrate. Converts the end product of pristanic acid beta oxidation, 4,8-dimethylnonanoyl-CoA, to its corresponding carnitine ester.

Subunit / interactions. Monomer.

Subcellular location. Peroxisome.

Pathway. Lipid metabolism; fatty acid beta-oxidation.

Similarity. Belongs to the carnitine/choline acetyltransferase family.

Isoforms (3)

UniProt IDNamesCanonical?
Q9UKG9-11yes
Q9UKG9-22
Q9UKG9-33

RefSeq proteins (3): NP_001137407, NP_001230674, NP_066974* (*=MANE)

Domains & families (InterPro)

IDNameType
IPR000542Carn_acyl_transFamily
IPR023213CAT-like_dom_sfHomologous_superfamily
IPR039551Cho/carn_acyl_trans_1_2Domain
IPR042231Cho/carn_acyl_trans_2Homologous_superfamily
IPR042572Carn_acyl_trans_NHomologous_superfamily

Pfam: PF00755

Enzyme classification (BRENDA):

  • EC 2.3.1.137 — carnitine O-octanoyltransferase (BRENDA: 12 organisms, 103 substrates, 23 inhibitors, 63 Km, 1 kcat entries)

Substrate kinetics (BRENDA)

19 substrates with measured Km, best-characterized 15. Km ranges are aggregated across organisms/conditions.

SubstrateKm (mM)Measurements
DECANOYL-COA0.0002–0.79421
L-CARNITINE0.0948–16016
PALMITOYL-COA0.0005–0.65
ACETYL-COA0.077–163
ACYL-COA0.002–0.0343
OCTANOYL-COA0.015–0.0242
ACETYL-L-CARNITINE0.7831
BUTYRYL-COA0.0581
CHOLINE1431
COA0.00741
COASH0.111
DECANOYL-L-CARNITINE8.41
HEXADECANOYL-L-CARNITINE0.0361
HEXANOYL-COA0.0551
L-ACYLCARNITINE0.00741

Catalyzed reactions (Rhea), 2 shown:

  • octanoyl-CoA + (R)-carnitine = O-octanoyl-(R)-carnitine + CoA (RHEA:17177)
  • 4,8-dimethylnonanoyl-CoA + (R)-carnitine = O-4,8-dimethylnonanoyl-(R)-carnitine + CoA (RHEA:44860)

UniProt features (20 total): modified residue 5, binding site 5, splice variant 3, sequence variant 2, sequence conflict 2, chain 1, short sequence motif 1, active site 1

Structure

Experimental structures (PDB)

0 structures.

Predicted structure (AlphaFold)

ModelpLDDTFraction very-high
AF-Q9UKG9-F197.220.98

Functional residue map

Curated UniProt residues grouped by drug-discovery relevance — catalytic, ligand-binding, modification, and mutation-validated positions. Source: UniProtKB sequence features.

Catalytic / active sites (1): 327 (proton acceptor)

Ligand- & substrate-binding residues (5): 406; 410–417; 439; 441; 452

Post-translational modifications (5): 57, 406, 406, 1, 40

Function

Pathways and Gene Ontology

Reactome pathways

2 pathways

IDPathway
R-HSA-389887Beta-oxidation of pristanoyl-CoA
R-HSA-9033241Peroxisomal protein import

MSigDB gene sets: 234 (showing top): GSE45365_HEALTHY_VS_MCMV_INFECTION_CD8_TCELL_IFNAR_KO_UP, GSE45365_NK_CELL_VS_CD8A_DC_MCMV_INFECTION_DN, GOBP_LIPID_MODIFICATION, GOBP_FATTY_ACID_CATABOLIC_PROCESS, LEE_NEURAL_CREST_STEM_CELL_DN, GOBP_COENZYME_A_METABOLIC_PROCESS, GRAESSMANN_APOPTOSIS_BY_DOXORUBICIN_UP, GRAESSMANN_RESPONSE_TO_MC_AND_DOXORUBICIN_UP, GOBP_ORGANOPHOSPHATE_METABOLIC_PROCESS, GOBP_MONOCARBOXYLIC_ACID_METABOLIC_PROCESS, GOBP_ORGANIC_ACID_TRANSPORT, GOBP_NUCLEOBASE_CONTAINING_SMALL_MOLECULE_METABOLIC_PROCESS, GOBP_GENERATION_OF_PRECURSOR_METABOLITES_AND_ENERGY, GOBP_FATTY_ACID_BETA_OXIDATION_USING_ACYL_COA_OXIDASE, NF1_Q6_01

GO Biological Process (9): generation of precursor metabolites and energy (GO:0006091), fatty acid metabolic process (GO:0006631), fatty acid beta-oxidation (GO:0006635), carnitine metabolic process (GO:0009437), fatty acid transport (GO:0015908), coenzyme A metabolic process (GO:0015936), fatty acid beta-oxidation using acyl-CoA oxidase (GO:0033540), medium-chain fatty acid metabolic process (GO:0051791), lipid metabolic process (GO:0006629)

GO Molecular Function (4): carnitine O-octanoyltransferase activity (GO:0008458), protein binding (GO:0005515), transferase activity (GO:0016740), acyltransferase activity (GO:0016746)

GO Cellular Component (3): peroxisome (GO:0005777), peroxisomal matrix (GO:0005782), cytosol (GO:0005829)

Reactome top-level categories

Rollup of top-2 pathways:

CategoryPathways
Peroxisomal lipid metabolism1
Protein localization1

GO top-level categories

Rollup of top GO terms by namespace:

CategoryTerms
metabolic process1
lipid metabolic process1
monocarboxylic acid metabolic process1
fatty acid catabolic process1
fatty acid ligase activity1
fatty acid oxidation1
amino-acid betaine metabolic process1
lipid transport1
monocarboxylic acid transport1
nucleoside phosphate metabolic process1
sulfur compound metabolic process1
purine-containing compound metabolic process1
fatty acid beta-oxidation1
fatty acid metabolic process1
primary metabolic process1
carnitine O-acyltransferase activity1
binding1
catalytic activity1
transferase activity1
microbody1
peroxisome1
microbody lumen1
cytoplasm1
cellular anatomical structure1

Protein interactions and networks

STRING

917 interactions, top by confidence (×1000):

Protein AProtein BPartner UniProtScore
CROTHADHBP55084777
CROTHADHQ16836706
CROTSREBF2Q12772622
CROTABCA1O95477614
CROTECHS1P30084593
CROTNPC1O15118570
CROTSREBF1P36956567
CROTABCG1P45844554
CROTACAA1P09110542
CROTRUNDC3BQ96NL0538
CROTPRKAA1Q13131529
CROTATP8B1O43520497
CROTACOX3O15254487
CROTECH1Q13011483
CROTSLC25A20O43772483

IntAct

9 interactions, top by confidence:

ABTypeScore
ALBCNOT1psi-mi:“MI:0914”(association)0.350
CROTFBP1psi-mi:“MI:0914”(association)0.350
CD36TTMPpsi-mi:“MI:0914”(association)0.350
GAS2L2ANKRD17psi-mi:“MI:0914”(association)0.350
CROTKLHDC4psi-mi:“MI:0914”(association)0.350
FECHPOTEFpsi-mi:“MI:0914”(association)0.350
CATVWA8psi-mi:“MI:2364”(proximity)0.270

BioGRID (25): VWA9 (Affinity Capture-MS), EIF2AK4 (Affinity Capture-MS), KLHDC4 (Affinity Capture-MS), USP25 (Affinity Capture-MS), CROT (Affinity Capture-MS), KLHDC4 (Affinity Capture-MS), USP25 (Affinity Capture-MS), FBP1 (Affinity Capture-MS), EIF2AK4 (Affinity Capture-MS), GATAD2B (Affinity Capture-MS), CROT (Proximity Label-MS), CROT (Proximity Label-MS), CROT (Affinity Capture-MS), CROT (Affinity Capture-MS), USP25 (Affinity Capture-MS)

ESM2 similar proteins: A2RTX5, A2Z8S0, B2ZGJ1, F1LN46, O19094, P07668, P11035, P11466, P13222, P17569, P18886, P23786, P28329, P32198, P32738, P32756, P32796, P36859, P43155, P47934, P49696, P50416, P52825, P52826, P56523, P80235, P97742, Q03059, Q0V9S0, Q2KJB7, Q58DK1, Q5U3U3, Q60HG9, Q63704, Q68Y62, Q6P4X5, Q704S8, Q75G68, Q7ZXE1, Q80VY9

Diamond homologs: B2ZGJ1, O19094, P11466, P13222, P18886, P32198, P32738, P43155, P47934, P52825, P52826, Q704S8, Q9DC50, Q9UKG9, P28329, P50416, P97742, Q03059, Q8HY46, Q92523, P23786, P80235, Q2KJB7, Q5U3U3, Q60HG9, Q6P4X5, Q7ZXE1, F1LN46, P07668, P32756, P32796, Q58DK1, Q63704, Q68Y62, Q90YJ9, Q924X2, Q8BGD5, Q8TCG5, Q00614

SIGNOR signaling

0 interactions.

Disease & clinical

Clinical variants and AI predictions

ClinVar

39 variants total. Per-class counts are floors (≥ shown; pagination cap):

ClassificationCount (floor)
Pathogenic0
Likely pathogenic0
Uncertain significance30
Likely benign1
Benign1

Top pathogenic / likely-pathogenic (0)

SpliceAI

2437 predictions. Top by Δscore:

VariantEffectΔscore
7:87346338:A:AGacceptor_gain1.0000
7:87346339:G:GGacceptor_gain1.0000
7:87346427:ACTGG:Adonor_loss1.0000
7:87346429:TGGTA:Tdonor_loss1.0000
7:87346430:GGT:Gdonor_loss1.0000
7:87346431:G:GAdonor_loss1.0000
7:87346432:T:Gdonor_loss1.0000
7:87349043:TTTA:Tacceptor_loss1.0000
7:87349044:TTAGG:Tacceptor_loss1.0000
7:87349045:TAGG:Tacceptor_loss1.0000
7:87349046:A:AGacceptor_gain1.0000
7:87349046:AG:Aacceptor_gain1.0000
7:87349047:G:GCacceptor_loss1.0000
7:87349047:G:GGacceptor_gain1.0000
7:87349047:GG:Gacceptor_gain1.0000
7:87349180:TCAGG:Tdonor_loss1.0000
7:87349184:G:GAdonor_loss1.0000
7:87349184:G:GGdonor_gain1.0000
7:87349185:T:Gdonor_loss1.0000
7:87359204:A:AGacceptor_gain1.0000
7:87359205:G:GGacceptor_gain1.0000
7:87359205:GT:Gacceptor_gain1.0000
7:87359317:G:GTdonor_gain1.0000
7:87359318:A:Tdonor_gain1.0000
7:87359323:GAAAT:Gdonor_gain1.0000
7:87359327:T:Gdonor_gain1.0000
7:87359327:T:TGdonor_gain1.0000
7:87361501:G:GTdonor_gain1.0000
7:87361502:A:Tdonor_gain1.0000
7:87361523:G:GTdonor_gain1.0000

AlphaMissense

4027 scored. Top likely-pathogenic:

VariantProtein changeam_pathogenicity
7:87377388:T:AW306R0.997
7:87377388:T:CW306R0.997
7:87391638:C:AR451S0.997
7:87391639:G:CR451P0.997
7:87392979:A:CS544R0.997
7:87392981:T:AS544R0.997
7:87392981:T:GS544R0.997
7:87375832:G:CR252P0.996
7:87391680:T:AW465R0.996
7:87391680:T:CW465R0.996
7:87359328:T:AW80R0.995
7:87359328:T:CW80R0.995
7:87375637:T:CL221P0.995
7:87375717:T:AW248R0.995
7:87375717:T:CW248R0.995
7:87375891:A:CS272R0.995
7:87375893:T:AS272R0.995
7:87375893:T:GS272R0.995
7:87361402:T:AW85R0.994
7:87361402:T:CW85R0.994
7:87361825:G:CD174H0.994
7:87377394:G:CD308H0.994
7:87381923:A:TD331V0.994
7:87391636:G:AG450D0.994
7:87369424:G:CR199P0.993
7:87377390:G:CW306C0.993
7:87377390:G:TW306C0.993
7:87391609:C:TT441I0.993
7:87392980:G:TS544I0.993
7:87381912:T:AH327Q0.992

dbSNP variants (sampled 300 via entrez): RS1000088915 (7:87389713 T>A,C), RS1000158745 (7:87358338 C>T), RS1000198256 (7:87368314 T>A), RS1000198773 (7:87377287 A>G), RS1000468452 (7:87346069 G>A), RS1000541873 (7:87369995 A>G), RS1000651115 (7:87350477 G>A), RS1000654141 (7:87376930 G>A), RS1000719203 (7:87351905 C>T), RS1000792315 (7:87375226 A>G), RS1000804986 (7:87345216 G>A,C), RS1000849009 (7:87389448 AG>A), RS1000893678 (7:87370236 G>A), RS1000927458 (7:87349988 T>C), RS1000934366 (7:87396909 T>C)

Disease associations

OMIM: gene MIM:606090 | disease phenotypes:

GenCC curated gene-disease

Mondo (0):

Orphanet (0):

HPO phenotypes

0 total (0 of 0 shown, HPO-id order):

GWAS associations

2 associations (top):

StudyTraitp-value
GCST004748_126Lung cancer1.000000e-06
GCST006585_1202Blood protein levels2.000000e-13

Drugs & pharmacology

Drug and pharmacology data

Is drug target: yes

ChEMBL targets (1): CHEMBL2206 (SINGLE PROTEIN)

PharmGKB: 1 entry (VIP=true, CPIC=false)

CTD chemical–gene interactions

58 total (human), top 30 by PubMed support.

ChemicalActions (top 5)PubMed papers
Valproic Acidaffects expression, decreases methylation, increases expression5
Cyclosporinedecreases expression4
trichostatin Aaffects cotreatment, decreases expression, increases expression3
bisphenol Aincreases methylation, decreases expression2
sodium arsenitedecreases expression, affects cotreatment, increases abundance, increases expression2
Air Pollutantsdecreases expression, increases abundance2
Arsenicincreases methylation, affects cotreatment, increases abundance, increases expression2
Phenylmercuric Acetateaffects cotreatment, increases expression2
Aflatoxin B1decreases methylation, increases expression2
2,4,6-tribromophenolincreases expression1
methylmercuric chloridedecreases expression1
triphenyl phosphateaffects expression1
glycidyl methacrylatedecreases expression1
decabromobiphenyl etherincreases expression1
tris(2-butoxyethyl) phosphateaffects expression1
perfluorooctanoic acidincreases expression1
manganese chlorideaffects cotreatment, increases abundance, increases expression1
potassium chromate(VI)decreases expression, affects cotreatment1
S-(1,2-dichlorovinyl)cysteineaffects response to substance, increases expression1
epigallocatechin gallateaffects cotreatment, decreases expression1
di-n-butylphosphoric acidaffects expression1
CGP 52608affects binding, increases reaction1
perfluoro-n-nonanoic aciddecreases expression1
entinostatdecreases expression, affects cotreatment1
4-(5-benzo(1,3)dioxol-5-yl-4-pyridin-2-yl-1H-imidazol-2-yl)benzamideaffects cotreatment, decreases expression, increases expression1
abrinedecreases expression1
2,2’,4,4’-tetrabromodiphenyl etherdecreases expression1
dorsomorphinaffects cotreatment, decreases expression, increases expression1
pentabrominated diphenyl ether 100decreases expression1
jinfukangaffects cotreatment, increases expression1

ChEMBL screening assays

4 unique, capped per target: 4 binding

Representative assays (with source publication via chembl_document):

Assay IDTypeDescriptionSource paper
CHEMBL5658344BindingInhibition of COT (unknown origin) at 100 nM relative to controlSelective JAK3 Inhibitors with a Covalent Reversible Binding Mode Targeting a New Induced Fit Binding Pocket. — Cell Chem Biol

Clinical trials (associated diseases)

0 trials via MONDO — disease-level, not drug-specific.

No linked Atlas pages yet — the cross-entity mesh grows as the corpus expands.