DEFB107B

Summary

DEFB107B (defensin beta 107B, HGNC:31918) is a protein-coding gene on chromosome 8p23.1, encoding Beta-defensin 107 (Q8IZN7). Has antibacterial activity.

Defensins form a family of antimicrobial and cytotoxic peptides made by neutrophils. Defensins are short, processed peptide molecules that are classified by structure into three groups: alpha-defensins, beta-defensins and theta-defensins. All beta-defensin genes are densely clustered in four to five syntenic chromosomal regions. Chromosome 8p23 contains at least two copies of the duplicated beta-defensin cluster. This duplication results in two identical copies of defensin, beta 107, DEFB107A and DEFB107B, in tail-to-tail orientation. This gene, DEFB107B, represents the more telomeric copy.

Source: NCBI Gene 503614 — RefSeq curated summary.

At a glance

• Clinical variants (ClinVar): 1 total
• MANE Select transcript: NM_001040705

Identifiers

Gene identifiers

Field	Value
HGNC ID	HGNC:31918
Approved symbol	DEFB107B
Name	defensin beta 107B
Location	8p23.1
Locus type	gene with protein product
Status	Approved
Aliases	HsT21816
Ensembl gene	ENSG00000198129
Ensembl biotype	protein_coding
Entrez	503614

Gene structure

Transcript identifiers

Ensembl transcripts: 1 — 1 protein_coding

ENST00000355602

RefSeq mRNA: 1 — MANE Select: NM_001040705 NM_001040705

CCDS: CCDS43696

Canonical transcript exons

ENST00000355602 — 2 exons

Exon	Start	End
ENSE00001664881	7509081	7509311
ENSE00001741579	7495911	7496003

Expression profiles

Bgee: expression breadth broad, 45 present calls, max score 56.38.

FANTOM5 (CAGE): breadth tissue_specific, TPM avg 0.0296 / max 52.3278, expressed in 2 samples.

FANTOM5 promoters (1 alternative TSS)

Promoter ID	TPM avg	Samples expressed
205051	0.0296	2

Top tissues by expression

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

Tissue	Anatomy ID	Expression score	Quality
lower esophagus mucosa	UBERON:0035834	56.38	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
endometrium	UBERON:0001295	31.26	silver 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
prefrontal cortex	UBERON:0000451	29.04	gold quality
ectocervix	UBERON:0012249	28.81	gold quality
monocyte	CL:0000576	28.56	gold quality
leukocyte	CL:0000738	28.47	gold quality
duodenum	UBERON:0002114	28.14	gold quality
uterine cervix	UBERON:0000002	27.78	gold quality
lymph node	UBERON:0000029	27.57	gold quality
tonsil	UBERON:0002372	27.05	gold quality
blood	UBERON:0000178	26.70	gold quality
islet of Langerhans	UBERON:0000006	26.55	gold quality
vermiform appendix	UBERON:0001154	26.42	gold quality
gall bladder	UBERON:0002110	25.98	gold quality
olfactory segment of nasal mucosa	UBERON:0005386	25.89	gold quality
placenta	UBERON:0001987	25.81	gold quality
urinary bladder	UBERON:0001255	25.72	gold quality
muscle of leg	UBERON:0001383	25.26	silver quality
fundus of stomach	UBERON:0001160	25.19	gold quality

Single-cell (SCXA)

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

Experiment	Marker?	Max mean expression
E-ANND-3	no	0.08

Regulation

Is transcription factor: no

Literature-anchored findings (GeneRIF, showing 1)

• This protein is thought to have antimicrobial activity. (PMID:16033865)

Cross-species orthologs

2 orthologs

Organism	Symbol	Gene ID
mus_musculus	Defb13	ENSMUSG00000044222
rattus_norvegicus	Defb13	ENSRNOG00000038157

Paralogs (1): DEFB107A (ENSG00000186572)

Protein

Protein identifiers

Beta-defensin 107 — Q8IZN7 (reviewed: Q8IZN7)

Alternative names: Beta-defensin 7, Defensin, beta 107

All UniProt accessions (1): Q8IZN7

UniProt curated annotations — full annotation on UniProt →

Function. Has antibacterial activity.

Subcellular location. Secreted.

Tissue specificity. Specifically expressed in testis.

Similarity. Belongs to the beta-defensin family.

RefSeq proteins (1): NP_001035795* (*=MANE)

Domains & families (InterPro)

ID	Name	Type
IPR025933	Beta_defensin_dom	Domain

Pfam: PF13841

UniProt features (5 total): disulfide bond 2, signal peptide 1, peptide 1, sequence conflict 1

Structure

Experimental structures (PDB)

0 structures.

Predicted structure (AlphaFold)

Model	pLDDT	Fraction very-high
AF-Q8IZN7-F1	83.39	0.30

Functional residue map

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

Disulfide bonds (2): 41–55, 45–64

Function

Pathways and Gene Ontology

Reactome pathways

2 pathways

ID	Pathway
R-HSA-1461957	Beta defensins
R-HSA-1461973	Defensins

MSigDB gene sets: 12 (showing top): REACTOME_INNATE_IMMUNE_SYSTEM, GOBP_DEFENSE_RESPONSE_TO_OTHER_ORGANISM, GOBP_DEFENSE_RESPONSE_TO_GRAM_NEGATIVE_BACTERIUM, GOBP_DEFENSE_RESPONSE_TO_GRAM_POSITIVE_BACTERIUM, GOBP_DEFENSE_RESPONSE_TO_BACTERIUM, GOBP_RESPONSE_TO_BACTERIUM, GOMF_LIPID_BINDING, REACTOME_ANTIMICROBIAL_PEPTIDES, GOBP_BIOLOGICAL_PROCESS_INVOLVED_IN_INTERSPECIES_INTERACTION_BETWEEN_ORGANISMS, REACTOME_DEFENSINS, REACTOME_BETA_DEFENSINS, chr8p23

GO Biological Process (3): defense response to bacterium (GO:0042742), innate immune response (GO:0045087), defense response (GO:0006952)

GO Molecular Function (1): lipid binding (GO:0008289)

GO Cellular Component (1): extracellular region (GO:0005576)

Reactome top-level categories

Rollup of top-2 pathways:

Category	Pathways
Defensins	1
Antimicrobial peptides	1

GO top-level categories

Rollup of top GO terms by namespace:

Category	Terms
defense response	1
response to bacterium	1
immune response	1
defense response to symbiont	1
response to stress	1
binding	1
cellular anatomical structure	1

Protein interactions and networks

STRING

180 interactions, top by confidence (×1000):

Protein A	Protein B	Partner UniProt	Score
DEFB107B	DEFB105A	Q8NG35	883
DEFB107B	DEFB106A	Q8N104	865
DEFB107B	DEFB104A	Q8WTQ1	831
DEFB107B	A0A0G2JN59	A0A0G2JN59	825
DEFB107B	DEFB103A	P81534	770
DEFB107B	DEFB108B	Q8NET1	749
DEFB107B	DEFB110	Q30KQ9	697
DEFB107B	DEFB1	P60022	690
DEFB107B	PRR23D1	E9PI22	661
DEFB107B	USP17L4	A6NCW7	584
DEFB107B	USP17L7	P0C7H9	573
DEFB107B	FAM90A10	A6NDY2	572
DEFB107B	PRR23B	Q6ZRT6	545
DEFB107B	PRR23A	A6NEV1	545
DEFB107B	DEFA5	Q01523	519

IntAct

2 interactions, top by confidence:

A	B	Type	Score
DEFB107A	ZZEF1	psi-mi:“MI:0914”(association)	0.350

BioGRID (12): SPIN3 (Affinity Capture-MS), HSPA5 (Affinity Capture-MS), LEPR (Affinity Capture-MS), ITGA4 (Affinity Capture-MS), SPIN2B (Affinity Capture-MS), IDE (Affinity Capture-MS), SPIN1 (Affinity Capture-MS), CACNA2D2 (Affinity Capture-MS), SUSD1 (Affinity Capture-MS), ZZEF1 (Affinity Capture-MS), ADAM11 (Affinity Capture-MS), MICA (Affinity Capture-MS)

ESM2 similar proteins: A0A7G6KN55, A4H200, A4H215, A4H216, A4H217, A4H218, A4H235, A4H236, A8MXU0, O18794, P0C8A7, P46156, P46157, P46158, P60022, P61261, P61262, P61263, P80392, P81534, Q0E4V3, Q0W9P9, Q30KK5, Q30KN4, Q30KP9, Q30KU3, Q32ZF8, Q32ZG2, Q32ZH8, Q32ZI4, Q5IAA9, Q5J5D0, Q5J5Z9, Q6QLR1, Q7JGL8, Q7JGL9, Q7JGM0, Q7JGM1, Q7JGM2, Q8IZN7

Diamond homologs: A4H215, A4H216, A4H217, A4H218, P0C8A7, Q32ZH8, Q5IAA9, Q8IZN7, Q8R2I4

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

120 predictions. Top by Δscore:

Variant	Effect	Δscore
8:7496003:GGTAA:G	donor_loss	0.9600
8:7496004:G:GA	donor_loss	0.9600
8:7496005:T:A	donor_loss	0.9600
8:7509079:AGC:A	acceptor_gain	0.8400
8:7496004:G:GG	donor_gain	0.8100
8:7498965:GAT:G	donor_gain	0.8100
8:7498843:T:G	acceptor_gain	0.7800
8:7498864:A:AG	acceptor_gain	0.7800
8:7498860:C:CA	acceptor_gain	0.7700
8:7505843:T:G	donor_gain	0.7700
8:7500705:TAGA:T	acceptor_gain	0.7500
8:7498920:T:G	donor_gain	0.7400
8:7498842:A:AG	acceptor_gain	0.7300
8:7498865:A:G	acceptor_gain	0.7300
8:7498841:C:G	acceptor_gain	0.7100
8:7496002:AG:A	donor_gain	0.6900
8:7496003:GG:G	donor_gain	0.6900
8:7509078:TAG:T	acceptor_gain	0.6900
8:7498957:C:T	donor_gain	0.5300
8:7498840:A:AG	acceptor_gain	0.5200
8:7500704:CTAGA:C	acceptor_gain	0.4900
8:7500706:AGATA:A	acceptor_gain	0.4900
8:7498988:T:TA	donor_gain	0.4800
8:7498989:A:AA	donor_gain	0.4800
8:7498920:T:TG	donor_gain	0.4600
8:7498869:C:A	acceptor_gain	0.4500
8:7496094:TTCC:T	donor_gain	0.4400
8:7509076:CTT:C	acceptor_gain	0.4400
8:7496001:AAG:A	donor_gain	0.4300
8:7509098:A:C	acceptor_gain	0.4300

AlphaMissense

463 scored. Top likely-pathogenic:

dbSNP variants (sampled 300 via entrez): RS1000529030 (8:7500671 T>A), RS1001153071 (8:7497573 C>A,G), RS1004999939 (8:7508187 G>A), RS1005338447 (8:7504151 C>G), RS1007870527 (8:7497072 T>C), RS1008315682 (8:7494058 G>A,C,T), RS1012437693 (8:7500831 C>G,T), RS1012839888 (8:7497647 T>C,G), RS1014960293 (8:7504162 C>G), RS1019524377 (8:7508466 T>G), RS1021177884 (8:7494148 G>A), RS10216932 (8:7503213 A>G,T), RS1025032346 (8:7497690 C>G,T), RS1025537596 (8:7500906 T>G), RS1026881833 (8:7504222 A>G)

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

4 total (human), top 4 by PubMed support.

Chemical	Actions (top 5)	PubMed papers
Cadmium	decreases expression, increases abundance	1
Aflatoxin B1	increases methylation	1
Cadmium Chloride	increases abundance, decreases expression	1
Acrylamide	increases expression	1

Clinical trials (associated diseases)

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