KRTAP13-2

Summary

KRTAP13-2 (keratin associated protein 13-2, HGNC:18923) is a protein-coding gene on chromosome 21q22.11, encoding Keratin-associated protein 13-2 (Q52LG2). 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 enable structural molecule activity. Predicted to be located in cytosol.

Source: NCBI Gene 337959 — RefSeq curated summary.

At a glance

• Clinical variants (ClinVar): 36 total
• MANE Select transcript: NM_181621

Identifiers

Gene identifiers

Field	Value
HGNC ID	HGNC:18923
Approved symbol	KRTAP13-2
Name	keratin associated protein 13-2
Location	21q22.11
Locus type	gene with protein product
Status	Approved
Aliases	KAP13-2
Ensembl gene	ENSG00000182816
Ensembl biotype	protein_coding
Entrez	337959

Gene structure

Transcript identifiers

Ensembl transcripts: 1 — 1 protein_coding

ENST00000399889

RefSeq mRNA: 1 — MANE Select: NM_181621 NM_181621

CCDS: CCDS13589

Canonical transcript exons

ENST00000399889 — 1 exons

Exon	Start	End
ENSE00001540640	30371390	30372271

Expression profiles

Bgee: expression breadth broad, 27 present calls, max score 65.16.

FANTOM5 (CAGE): breadth tissue_specific, TPM avg 0.0607 / max 42.7273, expressed in 11 samples.

FANTOM5 promoters (1 alternative TSS)

Promoter ID	TPM avg	Samples expressed
190123	0.0607	11

Top tissues by expression

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

Tissue	Anatomy ID	Expression score	Quality
rectum	UBERON:0001052	65.16	gold quality
transverse colon	UBERON:0001157	45.69	gold quality
colon	UBERON:0001155	37.77	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
intestine	UBERON:0000160	36.34	gold quality
bone marrow cell	CL:0002092	36.16	gold quality
ganglionic eminence	UBERON:0004023	35.49	gold quality
prostate gland	UBERON:0002367	34.82	gold quality
skin of abdomen	UBERON:0001416	33.71	gold quality
skeletal muscle tissue	UBERON:0001134	33.38	gold quality
small intestine Peyer’s patch	UBERON:0003454	32.48	gold quality
small intestine	UBERON:0002108	32.29	gold quality
zone of skin	UBERON:0000014	32.19	gold quality
hindlimb stylopod muscle	UBERON:0004252	32.15	gold quality
bone marrow	UBERON:0002371	31.74	gold quality
right lung	UBERON:0002167	31.51	silver quality
skin of leg	UBERON:0001511	31.22	gold quality
sural nerve	UBERON:0015488	30.93	gold quality
stromal cell of endometrium	CL:0002255	29.87	gold quality
smooth muscle tissue	UBERON:0001135	29.76	silver quality
muscle layer of sigmoid colon	UBERON:0035805	29.26	gold quality
liver	UBERON:0002107	29.23	gold quality
gall bladder	UBERON:0002110	29.14	gold quality
prefrontal cortex	UBERON:0000451	29.04	gold quality
duodenum	UBERON:0002114	28.14	gold quality
olfactory segment of nasal mucosa	UBERON:0005386	27.68	silver quality
lymph node	UBERON:0000029	27.57	gold quality
tonsil	UBERON:0002372	27.05	gold quality

Single-cell (SCXA)

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

Experiment	Marker?	Max mean expression
E-ANND-3	no	1.14

Regulation

Is transcription factor: no

miRNA regulators (miRDB)

12 targeting KRTAP13-2, top 30 by miRDB confidence (max_score; target_count = how many genes the miRNA targets in total — lower means more specific):

miRNA	Max score	Avg score	miRNA target_count
HSA-MIR-3646	100.00	73.56	5283
HSA-MIR-27A-3P	99.98	72.13	2955
HSA-MIR-27B-3P	99.98	72.13	2955
HSA-MIR-9985	99.98	72.11	2939
HSA-MIR-6885-3P	99.75	70.36	3187
HSA-MIR-4766-5P	99.75	69.23	2662
HSA-MIR-545-5P	99.66	70.18	2308
HSA-MIR-325	99.58	66.55	358
HSA-MIR-622	98.99	66.48	1050
HSA-MIR-421	98.90	67.04	1883
HSA-MIR-4709-5P	98.51	67.25	1335
HSA-MIR-6500-3P	97.42	67.20	867

Literature-anchored findings (GeneRIF, showing 1)

• The KRTAP13-2 promoter is activated by Trichostatin A (TSA) treatment according to promoter reporter assays in HEK 293 cells. (PMID:20494980)

Cross-species orthologs

2 orthologs

Organism	Symbol	Gene ID
mus_musculus	Krtap13-1	ENSMUSG00000056350
rattus_norvegicus	Krtap13-1	ENSRNOG00000042531

Paralogs (8): KRTAP11-1 (ENSG00000182591), KRTAP15-1 (ENSG00000186970), KRTAP13-4 (ENSG00000186971), KRTAP26-1 (ENSG00000197683), KRTAP13-1 (ENSG00000198390), KRTAP27-1 (ENSG00000206107), KRTAP25-1 (ENSG00000232263), KRTAP13-3 (ENSG00000240432)

Protein

Protein identifiers

Keratin-associated protein 13-2 — Q52LG2 (reviewed: Q52LG2)

All UniProt accessions (1): Q52LG2

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 PMG family.

RefSeq proteins (1): NP_853652* (*=MANE)

Domains & families (InterPro)

ID	Name	Type
IPR007659	Keratin_matx	Family
IPR007951	KRTAP_PMG	Family

Pfam: PF05287

UniProt features (9 total): repeat 5, sequence variant 2, chain 1, region of interest 1

Structure

Experimental structures (PDB)

0 structures.

Predicted structure (AlphaFold)

Model	pLDDT	Fraction very-high
AF-Q52LG2-F1	46.50	0.00

Function

Pathways and Gene Ontology

Reactome pathways

2 pathways

ID	Pathway
R-HSA-6805567	Keratinization
R-HSA-1266738	Developmental Biology

MSigDB gene sets: 44 (showing top): CATRRAGC_UNKNOWN, FREAC3_01, MARTINEZ_RB1_TARGETS_DN, BRN2_01, TGANTCA_AP1_C, TGACATY_UNKNOWN, YY1_01, YYCATTCAWW_UNKNOWN, chr21q22, GOCC_INTERMEDIATE_FILAMENT_CYTOSKELETON, GOCC_KERATIN_FILAMENT, YKACATTT_UNKNOWN, GOMF_STRUCTURAL_MOLECULE_ACTIVITY, CERIBELLI_PROMOTERS_INACTIVE_AND_BOUND_BY_NFY, GOCC_SUPRAMOLECULAR_COMPLEX

GO Biological Process (0):

GO Molecular Function (2): structural molecule activity (GO:0005198), protein binding (GO:0005515)

GO Cellular Component (3): cytosol (GO:0005829), keratin filament (GO:0045095), intermediate filament (GO:0005882)

Reactome top-level categories

Rollup of top-1 pathways:

Category	Pathways
Developmental Biology	1

GO top-level categories

Rollup of top GO terms by namespace:

Category	Terms
molecular_function	1
binding	1
cytoplasm	1
cellular anatomical structure	1
intermediate filament	1
intermediate filament cytoskeleton	1
polymeric cytoskeletal fiber	1

Protein interactions and networks

STRING

192 interactions, top by confidence (×1000):

Protein A	Protein B	Partner UniProt	Score
KRTAP13-2	KRTAP19-3	Q7Z4W3	720
KRTAP13-2	SRRM5	B3KS81	667
KRTAP13-2	KRTAP19-6	Q3LI70	623
KRTAP13-2	KRTAP19-2	Q3LHN2	590
KRTAP13-2	KRTAP19-5	Q3LI72	575
KRTAP13-2	KRTAP7-1	Q8IUC3	575
KRTAP13-2	OR1B1	Q8NGR6	573
KRTAP13-2	KRTAP19-1	Q8IUB9	570
KRTAP13-2	KRTAP1-1	Q07627	537
KRTAP13-2	KRTAP9-2	Q9BYQ4	524
KRTAP13-2	KRTAP8-1	Q8IUC2	513
KRTAP13-2	LCE2C	Q5TA81	445
KRTAP13-2	LCE2A	Q5TA79	435
KRTAP13-2	LCE2D	Q5TA82	434
KRTAP13-2	KRTAP10-11	P60412	412

IntAct

241 interactions, top by confidence:

A	B	Type	Score
NOTCH2NLC	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
CYSRT1	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
GEMIN4	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
KLHL38	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
KRTAP13-2	MAGOHB	psi-mi:“MI:0915”(physical association)	0.560
HOXA1	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
KRTAP13-2	TNS2	psi-mi:“MI:0915”(physical association)	0.560
STK16	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
KRTAP1-1	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
KRTAP12-2	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
KRTAP12-3	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
KRTAP13-2	SLC25A18	psi-mi:“MI:0915”(physical association)	0.560
KRTAP13-2	MEOX2	psi-mi:“MI:0915”(physical association)	0.560
KRTAP13-2	TSPYL6	psi-mi:“MI:0915”(physical association)	0.560
KRTAP13-2	SPMIP9	psi-mi:“MI:0915”(physical association)	0.560
KRTAP13-2	KRTAP9-2	psi-mi:“MI:0915”(physical association)	0.560
GATA3	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
KRTAP13-2	UNC5CL	psi-mi:“MI:0915”(physical association)	0.560
POU2AF1	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
KRTAP13-2	KRTAP4-5	psi-mi:“MI:0915”(physical association)	0.560
ZIC1	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
VGLL3	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
KRTAP13-2	SAXO4	psi-mi:“MI:0915”(physical association)	0.560
HNRNPH1	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
KRTAP13-2	KCTD9	psi-mi:“MI:0915”(physical association)	0.560
GRN	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
KRTAP10-5	KRTAP13-2	psi-mi:“MI:0915”(physical association)	0.560
KRTAP13-2	KPRP	psi-mi:“MI:0915”(physical association)	0.560

BioGRID (98): KRTAP13-2 (Two-hybrid), KRTAP13-2 (Two-hybrid), KRTAP13-2 (Two-hybrid), KRTAP13-2 (Two-hybrid), KRTAP13-2 (Two-hybrid), KRTAP13-2 (Two-hybrid), KRTAP13-2 (Two-hybrid), KRTAP13-2 (Two-hybrid), KRTAP13-2 (Two-hybrid), KRTAP13-2 (Two-hybrid), KRTAP13-2 (Two-hybrid), KRTAP13-2 (Two-hybrid), KRTAP13-2 (Two-hybrid), KRTAP13-2 (Two-hybrid), KRTAP13-2 (Two-hybrid)

ESM2 similar proteins: A8MUX0, O08640, O13152, O93499, O93500, P02438, P02439, P02440, P02448, P02449, P02450, P02451, P04458, P04459, P07521, P08131, P08335, P20307, P20308, P25692, P60329, Q05B44, Q24JX9, Q28580, Q3LI76, Q3LI77, Q3LI83, Q3SY46, Q4W7G7, Q4W7G8, Q4W7G9, Q4W7H0, Q4W7H1, Q52LG2, Q6PEX3, Q6R645, Q6R648, Q8IUC0, Q8IUC1, Q8IUC3

Diamond homologs: A1A580, Q3LI77, Q3SY46, Q4W7H0, Q4W7H1, Q52LG2, Q8IUC0, O08640, Q3LI76, Q4W7G7, Q4W7G8, Q4W7G9, Q6R645, Q9QZU5, Q8IUC1

SIGNOR signaling

0 interactions.

Enriched among interaction partners

Reactome pathways and GO biological processes over-represented among this gene’s 76 IntAct physical interaction partners (hypergeometric vs the genome-wide background, BH-FDR, gene-set size 15–500, ranked by fold). A functional readout of the neighbourhood — distinct from this gene’s own memberships above, and biased toward well-studied / hub proteins, so read it as themes rather than proof.

Reactome pathways:

Pathway	Partners	Fold	FDR
Keratinization	13	16.5×	7e-11

Disease & clinical

Clinical variants and AI predictions

ClinVar

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

Classification	Count (floor)
Pathogenic	0
Likely pathogenic	0
Uncertain significance	33
Likely benign	3
Benign	0

Top pathogenic / likely-pathogenic (0)

SpliceAI

403 predictions. Top by Δscore:

Variant	Effect	Δscore
21:30372167:C:CT	donor_gain	0.8000
21:30371815:T:TA	donor_gain	0.7600
21:30371855:A:AC	donor_gain	0.7600
21:30371856:C:CC	donor_gain	0.7600
21:30371914:TAGAG:T	donor_gain	0.7600
21:30371915:AGAGA:A	donor_gain	0.7600
21:30372138:G:C	donor_gain	0.7400
21:30372163:G:C	donor_gain	0.7400
21:30371837:C:CT	donor_gain	0.7200
21:30371662:A:AC	donor_gain	0.7000
21:30371663:C:CC	donor_gain	0.7000
21:30371689:G:C	donor_gain	0.6900
21:30371790:AG:A	donor_gain	0.6900
21:30371794:G:T	acceptor_gain	0.6800
21:30371910:AGCCT:A	acceptor_gain	0.6800
21:30371848:ACAG:A	donor_gain	0.6700
21:30371849:CAGC:C	donor_gain	0.6700
21:30371880:AG:A	donor_gain	0.6600
21:30372000:C:CA	donor_gain	0.6600
21:30371791:G:C	donor_gain	0.6400
21:30371838:C:CT	donor_gain	0.6400
21:30371911:GCCT:G	acceptor_gain	0.6400
21:30371462:A:AC	donor_gain	0.6300
21:30371463:C:CC	donor_gain	0.6300
21:30371549:G:A	donor_gain	0.6300
21:30371656:TGAGA:T	donor_gain	0.6300
21:30371793:C:CT	acceptor_gain	0.6300
21:30372190:T:A	donor_gain	0.6300
21:30372051:CC:C	acceptor_gain	0.6200
21:30372052:CC:C	acceptor_gain	0.6200

AlphaMissense

1103 scored. Top likely-pathogenic:

Variant	Protein change	am_pathogenicity
21:30371908:A:C	F102L	0.805
21:30371908:A:T	F102L	0.805
21:30371910:A:G	F102L	0.805
21:30371803:G:C	F137L	0.791
21:30371803:G:T	F137L	0.791
21:30371805:A:G	F137L	0.791
21:30371776:G:C	F146L	0.781
21:30371776:G:T	F146L	0.781
21:30371778:A:G	F146L	0.781
21:30371704:G:C	F170L	0.744
21:30371704:G:T	F170L	0.744
21:30371706:A:G	F170L	0.744
21:30372184:G:C	F10L	0.710
21:30372184:G:T	F10L	0.710
21:30372186:A:G	F10L	0.710

dbSNP variants (sampled 300 via entrez): RS1000010431 (21:30372975 C>T), RS1000043056 (21:30373216 A>C), RS1000874994 (21:30373869 C>T), RS1001929949 (21:30371663 CT>C), RS1002354362 (21:30374262 T>G), RS1002718791 (21:30373617 A>C), RS1003118790 (21:30373345 G>A,C), RS1003546482 (21:30371337 A>G), RS1003718944 (21:30372470 C>G,T), RS1004198558 (21:30372434 G>A,C), RS1005938400 (21:30373296 C>A), RS1006245974 (21:30373821 C>A), RS1006627324 (21:30373594 G>A), RS1007392540 (21:30370996 C>A), RS1011131955 (21:30372504 T>C)

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

8 total (human), top 8 by PubMed support.

Chemical	Actions (top 5)	PubMed papers
sodium arsenite	affects expression	2
perfluorooctanoic acid	increases expression	1
CGP 52608	affects binding, increases reaction	1
perfluoro-n-nonanoic acid	increases expression	1
perfluorohexanesulfonic acid	decreases expression	1
Grape Seed Proanthocyanidins	affects cotreatment, decreases expression	1
Benzo(a)pyrene	decreases methylation	1
Catechin	affects cotreatment, decreases expression	1

Clinical trials (associated diseases)

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