KRTAP20-4

Summary

KRTAP20-4 (keratin associated protein 20-4, HGNC:34002) is a protein-coding gene on chromosome 21q22.11, encoding Putative keratin-associated protein 20-4 (Q3LI62). In the hair cortex, hair keratin intermediate filaments are embedded in an interfilamentous matrix, consisting of hair keratin-associated proteins (KRTAP), which are essential for the formation of a rigid and resistant hair shaft through their extensive disulfide bond cross-link….

Predicted to be located in intermediate filament.

Source: NCBI Gene 100151643 — RefSeq curated summary.

At a glance

• Clinical variants (ClinVar): 1 total
• MANE Select transcript: NM_001350977

Identifiers

Gene identifiers

Field	Value
HGNC ID	HGNC:34002
Approved symbol	KRTAP20-4
Name	keratin associated protein 20-4
Location	21q22.11
Locus type	gene with protein product
Status	Approved
Aliases	KAP20.4
Ensembl gene	ENSG00000206105
Ensembl biotype	protein_coding
Entrez	100151643

Gene structure

Transcript identifiers

Ensembl transcripts: 1 — 1 protein_coding

ENST00000382828

RefSeq mRNA: 1 — MANE Select: NM_001350977 NM_001350977

CCDS: CCDS86982

Canonical transcript exons

ENST00000382828 — 1 exons

Exon	Start	End
ENSE00001493468	30620627	30620850

Expression profiles

Bgee: expression breadth broad, 24 present calls, max score 98.56.

Top tissues by expression

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

Tissue	Anatomy ID	Expression score	Quality
primordial germ cell in gonad	CL:0000670 ∩ UBERON:0000991	98.56	gold quality
male germ line stem cell (sensu Vertebrata) in testis	CL:0000089 ∩ UBERON:0000473	96.99	gold quality
right testis	UBERON:0004534	55.01	gold quality
left testis	UBERON:0004533	52.95	gold quality
testis	UBERON:0000473	52.27	gold quality
colonic epithelium	UBERON:0000397	37.20	gold quality
ventricular zone	UBERON:0003053	36.48	gold quality
cortical plate	UBERON:0005343	36.47	gold quality
bone marrow cell	CL:0002092	36.16	gold quality
ganglionic eminence	UBERON:0004023	35.49	gold quality
skeletal muscle tissue	UBERON:0001134	33.38	gold quality
hindlimb stylopod muscle	UBERON:0004252	32.15	gold quality
bone marrow	UBERON:0002371	31.74	gold quality
muscle tissue	UBERON:0002385	31.06	gold quality
sural nerve	UBERON:0015488	30.93	gold quality
stromal cell of endometrium	CL:0002255	29.87	gold quality
placenta	UBERON:0001987	29.51	gold quality
prefrontal cortex	UBERON:0000451	29.04	gold quality
duodenum	UBERON:0002114	28.14	gold quality
liver	UBERON:0002107	28.04	gold quality
lymph node	UBERON:0000029	27.57	gold quality
islet of Langerhans	UBERON:0000006	27.30	gold quality
tonsil	UBERON:0002372	27.05	gold quality
vermiform appendix	UBERON:0001154	26.42	gold quality
leukocyte	CL:0000738	26.23	gold quality
monocyte	CL:0000576	26.09	gold quality
gall bladder	UBERON:0002110	25.98	gold quality
blood	UBERON:0000178	25.96	gold quality
olfactory segment of nasal mucosa	UBERON:0005386	25.89	gold quality
urinary bladder	UBERON:0001255	25.72	gold quality

Single-cell (SCXA)

Detected in 1 experiment(s), a significant marker in 0.

Experiment	Marker?	Max mean expression
E-ANND-3	no	1.22

Regulation

Is transcription factor: no

Cross-species orthologs

0 orthologs

Protein

Protein identifiers

Putative keratin-associated protein 20-4 — Q3LI62 (reviewed: Q3LI62)

All UniProt accessions (1): Q3LI62

UniProt curated annotations — full annotation on UniProt →

Function. In the hair cortex, hair keratin intermediate filaments are embedded in an interfilamentous matrix, consisting of hair keratin-associated proteins (KRTAP), which are essential for the formation of a rigid and resistant hair shaft through their extensive disulfide bond cross-linking with abundant cysteine residues of hair keratins. The matrix proteins include the high-sulfur and high-glycine-tyrosine keratins.

Subunit / interactions. Interacts with hair keratins.

Similarity. Belongs to the KRTAP type 20 family.

RefSeq proteins (1): NP_001337906* (*=MANE)

Domains & families (InterPro)

UniProt features (1 total): chain 1

Structure

Experimental structures (PDB)

0 structures.

Predicted structure (AlphaFold)

Model	pLDDT	Fraction very-high
AF-Q3LI62-F1	57.74	0.00

Function

Pathways and Gene Ontology

Reactome pathways

0 pathways

MSigDB gene sets: 5 (showing top): chr21q22, GOCC_INTERMEDIATE_FILAMENT_CYTOSKELETON, GOCC_SUPRAMOLECULAR_COMPLEX, GOCC_POLYMERIC_CYTOSKELETAL_FIBER, GOCC_SUPRAMOLECULAR_POLYMER

GO Biological Process (0):

GO Molecular Function (0):

GO Cellular Component (1): intermediate filament (GO:0005882)

GO top-level categories

Rollup of top GO terms by namespace:

Category	Terms
intermediate filament cytoskeleton	1
polymeric cytoskeletal fiber	1

Protein interactions and networks

STRING

24 interactions, top by confidence (×1000):

Protein A	Protein B	Partner UniProt	Score
KRTAP20-4	GFOD1	Q9NXC2	724
KRTAP20-4	ARHGAP42	A6NI28	710
KRTAP20-4	ZNF629	Q9UEG4	310
KRTAP20-4	ZNF44	P15621	310
KRTAP20-4	K7ESF6	K7ESF6	310
KRTAP20-4	ZNF501	Q96CX3	310
KRTAP20-4	ZNF436	Q9C0F3	308
KRTAP20-4	ZNF569	Q5MCW4	306
KRTAP20-4	GFOD2	Q3B7J2	166
KRTAP20-4	OPHN1	O60890	161
KRTAP20-4	ARHGAP26	Q9UNA1	160
KRTAP20-4	KRTAP22-2	Q3LI68	0

IntAct

0 interactions, top by confidence:

ESM2 similar proteins: A1X8C6, C0HLA2, C0HLB8, C0HLK6, C0HLL0, D6C4J4, L8BU87, P01154, P04869, P0C577, P0C578, P0DJJ7, P0DKR4, P0DKT9, P0DKU3, P0DKU4, P0DL25, P0DM50, P0DMD2, P0DMG7, P0DOZ2, P0DUW7, P0DV82, P0DV97, P23252, P25436, P25513, P29137, P58516, P59069, P81056, P81720, P83048, P83604, P83629, P84886, P85060, P85062, P85198, P85217

SIGNOR signaling

0 interactions.

Disease & clinical

Clinical variants and AI predictions

ClinVar

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

Classification	Count (floor)
Pathogenic	0
Likely pathogenic	0
Uncertain significance	1
Likely benign	0
Benign	0

Top pathogenic / likely-pathogenic (0)

SpliceAI

35 predictions. Top by Δscore:

Variant	Effect	Δscore
21:30620740:C:G	donor_gain	0.6500
21:30620739:GC:G	donor_gain	0.6300
21:30620722:G:GT	donor_gain	0.6100
21:30620785:CCAG:C	donor_loss	0.5500
21:30620787:AG:A	donor_loss	0.5500
21:30620788:GGTAA:G	donor_loss	0.5500
21:30620789:G:A	donor_loss	0.5500
21:30620790:T:G	donor_loss	0.5500
21:30620722:G:T	donor_gain	0.5400
21:30620750:C:T	donor_gain	0.5200
21:30620685:G:GA	donor_gain	0.5100
21:30620716:C:G	donor_gain	0.5100
21:30620784:GCCAG:G	donor_gain	0.5100
21:30620755:GC:G	donor_gain	0.4500
21:30620830:T:G	donor_gain	0.4400
21:30620684:T:TA	donor_gain	0.3700
21:30620738:GGC:G	donor_gain	0.3700
21:30620789:G:GG	donor_gain	0.3300
21:30620791:A:C	donor_loss	0.3100
21:30620789:G:GC	donor_gain	0.3000
21:30620790:TAA:T	donor_gain	0.3000
21:30620788:G:GT	donor_gain	0.2800
21:30620736:GTGGC:G	donor_gain	0.2700
21:30620737:TGGCT:T	donor_gain	0.2700
21:30620738:GGCTG:G	donor_gain	0.2700
21:30620787:AGG:A	donor_gain	0.2700
21:30620791:A:T	donor_gain	0.2600
21:30620786:CAG:C	donor_gain	0.2500
21:30620768:C:A	acceptor_gain	0.2200
21:30620785:CCAGG:C	donor_gain	0.2200

AlphaMissense

272 scored. Top likely-pathogenic:

Variant	Protein change	am_pathogenicity
21:30620756:C:G	C33W	0.573

dbSNP variants (sampled 300 via entrez): RS1000768502 (21:30621193 C>A,G,T), RS1001759968 (21:30619245 C>T), RS1002982367 (21:30620848 T>C,G), RS1003220781 (21:30619625 C>T), RS1003294954 (21:30621124 T>C), RS1003725051 (21:30619205 G>A), RS1004420889 (21:30619262 G>A,C), RS1004909302 (21:30618745 A>G,T), RS1004929016 (21:30619561 G>T), RS1004981517 (21:30619127 G>A,T), RS1007170406 (21:30620408 A>G), RS1008493995 (21:30620395 CCAAGA>C), RS1011037472 (21:30619220 A>G), RS1012028621 (21:30621187 C>T), RS1016208325 (21:30618892 C>A)

Disease associations

OMIM: gene `` | disease phenotypes:

GenCC curated gene-disease

Mondo (0):

Orphanet (0):

HPO phenotypes

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

GWAS associations

0 associations (top):

Drugs & pharmacology

Drug and pharmacology data

Is drug target: no

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

CTD chemical–gene interactions

7 total (human), top 7 by PubMed support.

Chemical	Actions (top 5)	PubMed papers
bisphenol F	affects cotreatment, decreases methylation	1
bisphenol A	affects methylation	1
butyraldehyde	decreases expression	1
Resveratrol	affects cotreatment, decreases expression	1
Fulvestrant	decreases methylation, affects cotreatment	1
Endosulfan	increases expression	1
Plant Extracts	affects cotreatment, decreases expression	1

Clinical trials (associated diseases)

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