SNORD3A

Summary

SNORD3A (small nucleolar RNA, C/D box 3A, HGNC:33189) is a small nucleolar RNA gene on chromosome 17p11.2.

U3 RNA, an abundant small nucleolar RNA (snoRNA), is thought to play a role in the processing of ribosomal RNA precursors (Bernstein et al., 1983 [PubMed 6186397]).

Source: NCBI Gene 780851 — RefSeq curated summary.

At a glance

• Gene type: non-coding (snoRNA) — no protein product; not a drug target. Variant/disease associations are omitted (they would be positional, from an overlapping protein-coding gene).

Identifiers

Gene identifiers

Field	Value
HGNC ID	HGNC:33189
Approved symbol	SNORD3A
Name	small nucleolar RNA, C/D box 3A
Location	17p11.2
Locus type	RNA, small nucleolar
Status	Approved
Aliases	U3, RNU3
Ensembl gene	ENSG00000263934
Ensembl biotype	snoRNA
OMIM	180710
Entrez	780851
RNAcentral	URS000053962A — lncRNA, 217 nt, 2 organism(s)

Gene structure

Transcript identifiers

Ensembl transcripts: 1 — 1 snoRNA

ENST00000584923

RefSeq mRNA: 0 — MANE Select: None

Canonical transcript exons

ENST00000584923 — 1 exons

Exon	Start	End
ENSE00002693314	19188016	19188714

Expression profiles

Bgee: expression breadth ubiquitous, 132 present calls, max score 99.97.

FANTOM5 (CAGE): breadth broad, TPM avg 0.5851 / max 17.7092, expressed in 266 samples.

FANTOM5 promoters (1 alternative TSS)

Promoter ID	TPM avg	Samples expressed
159829	0.5851	266

Top tissues by expression

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

Tissue	Anatomy ID	Expression score	Quality
adrenal tissue	UBERON:0018303	99.97	gold quality
sural nerve	UBERON:0015488	99.87	gold quality
bone marrow cell	CL:0002092	98.80	gold quality
calcaneal tendon	UBERON:0003701	98.24	gold quality
bone marrow	UBERON:0002371	94.49	gold quality
lower esophagus mucosa	UBERON:0035834	92.59	gold quality
right testis	UBERON:0004534	92.45	gold quality
hindlimb stylopod muscle	UBERON:0004252	92.41	gold quality
mucosa of transverse colon	UBERON:0004991	92.34	gold quality
left testis	UBERON:0004533	91.27	gold quality
colonic epithelium	UBERON:0000397	90.87	gold quality
right uterine tube	UBERON:0001302	90.87	gold quality
testis	UBERON:0000473	90.12	gold quality
cortex of kidney	UBERON:0001225	86.83	gold quality
minor salivary gland	UBERON:0001830	86.70	gold quality
male germ line stem cell (sensu Vertebrata) in testis	CL:0000089 ∩ UBERON:0000473	86.66	gold quality
liver	UBERON:0002107	86.32	gold quality
granulocyte	CL:0000094	86.18	gold quality
apex of heart	UBERON:0002098	85.83	gold quality
saliva-secreting gland	UBERON:0001044	85.46	gold quality
monocyte	CL:0000576	85.23	gold quality
tibial nerve	UBERON:0001323	84.71	gold quality
right lobe of liver	UBERON:0001114	83.59	gold quality
kidney	UBERON:0002113	83.44	gold quality
corpus callosum	UBERON:0002336	83.41	gold quality
prostate gland	UBERON:0002367	83.07	gold quality
primary visual cortex	UBERON:0002436	83.03	gold quality
superior frontal gyrus	UBERON:0002661	81.54	gold quality
duodenum	UBERON:0002114	81.09	gold quality
placenta	UBERON:0001987	81.03	gold quality

Single-cell (SCXA)

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

Experiment	Marker?	Max mean expression
E-ANND-3	yes	22.03

Regulation

Is transcription factor: no

Literature-anchored findings (GeneRIF, showing 4)

• PHAX and CRM1 have roles in transporting U3 snoRNA to nucleoli (PMID:15574332)
• U3 snoRNP is assembled and matures in the nucleoplasm in a large dynamic multiprotein complex (PMID:15574333)
• Data show that U3 snoRNP assembly, and therefore U3 snoRNA accumulation, is regulated through the U3-specific protein hU3-55K. (PMID:21505065)
• LncRNA SNORD3A specifically sensitizes breast cancer cells to 5-FU by sponging miR-185-5p to enhance UMPS expression. (PMID:32382150)

Cross-species orthologs

0 orthologs

Protein

Non-coding RNA — no protein product; not a drug target.

Function

No curated pathway, Gene-Ontology, or interaction data.

Disease & clinical

No curated disease, variant, or cancer-driver associations.

Drugs & pharmacology

No drug or pharmacology data — not an established drug target.