IDH3B (isocitrate dehydrogenase (NAD(+)) 3 non-catalytic subunit beta)

Gene

• Entrez ID: 3420
• Gene name: Isocitrate dehydrogenase (NAD(+)) 3 non-catalytic subunit beta
• Gene symbol: IDH3B
• Synonyms: RP46
• Chromosome: 20
• Chromosome location: 20p13
• Summary: Isocitrate dehydrogenases catalyze the oxidative decarboxylation of isocitrate to 2-oxoglutarate. These enzymes belong to two distinct subclasses, one of which utilizes NAD(+) as the electron acceptor and the other NADP(+). Five isocitrate dehydrogenases have been reported: three NAD(+)-dependent isocitrate dehydrogenases, which localize to the mitochondrial matrix, and two NADP(+)-dependent isocitrate dehydrogenases, one of which is mitochondrial and the other predominantly cytosolic. NAD(+)-dependent isocitrate dehydrogenases catalyze the allosterically regulated rate-limiting step of the tricarboxylic acid cycle. Each isozyme is a heterotetramer that is composed of two alpha subunits, one beta subunit, and one gamma subunit. The protein encoded by this gene is the beta subunit of one isozyme of NAD(+)-dependent isocitrate dehydrogenase. Multiple alternatively spliced transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Sep 2016]

SNPs

SNP ID	Visualize variation	Clinical significance	Consequence
rs137853020	A>G	Pathogenic	Coding sequence variant, non coding transcript variant, missense variant
rs191680997	G>A,T	Conflicting-interpretations-of-pathogenicity, uncertain-significance, benign	Intron variant
rs747812567	G>-	Likely-pathogenic	Coding sequence variant, non coding transcript variant, frameshift variant
rs776399707	C>T	Conflicting-interpretations-of-pathogenicity	Non coding transcript variant, coding sequence variant, synonymous variant
rs1600169350	T>-	Pathogenic	Non coding transcript variant, coding sequence variant, frameshift variant

miRNA

miRTarBase ID	miRNA	Experiments	Reference
MIRT035766	hsa-miR-103a-2-5p	CLASH	23622248
MIRT040424	hsa-miR-615-3p	CLASH	23622248
MIRT043662	hsa-miR-342-3p	CLASH	23622248
MIRT717079	hsa-miR-197-3p	HITS-CLIP	19536157
MIRT717080	hsa-miR-4709-5p	HITS-CLIP	19536157
MIRT717081	hsa-miR-6884-3p	HITS-CLIP	19536157

Gene ontology (GO)

GO ID	Ontology	Definition	Evidence	Reference
GO:0000287	Function	Magnesium ion binding	IEA
GO:0004449	Function	Isocitrate dehydrogenase (NAD+) activity	IBA	21873635
GO:0005634	Component	Nucleus	HDA	21630459
GO:0005739	Component	Mitochondrion	IBA	21873635
GO:0005739	Component	Mitochondrion	IDA
GO:0005759	Component	Mitochondrial matrix	TAS
GO:0006099	Process	Tricarboxylic acid cycle	IBA	21873635
GO:0006099	Process	Tricarboxylic acid cycle	TAS
GO:0006102	Process	Isocitrate metabolic process	IBA	21873635
GO:0009055	Function	Electron transfer activity	TAS	10601238
GO:0022900	Process	Electron transport chain	IEA
GO:0051287	Function	NAD binding	IEA

Other IDs

• MIM: 604526
• HGNC: 5385
• e!Ensembl: ENSG00000101365

Protein

• UniProt ID: O43837
• Protein name: Isocitrate dehydrogenase [NAD] subunit beta, mitochondrial (Isocitric dehydrogenase subunit beta) (NAD(+)-specific ICDH subunit beta)
• Protein function: Plays a structural role to facilitate the assembly and ensure the full activity of the enzyme catalyzing the decarboxylation of isocitrate (ICT) into alpha-ketoglutarate. The heterodimer composed of the alpha (IDH3A) and beta (IDH3B) subunits and the heterodimer composed of the alpha (IDH3A) and gamma (IDH3G) subunits, have considerable basal activity but the full activity of the heterotetramer (containing two subunits of IDH3A, one of IDH3B and one of IDH3G) requires the assembly and cooperative function of both heterodimers.
• PDB: 6KDE, 6KDF, 6KDY, 6KE3, 7CE3
• Family and domains:

  Pfam

  Accession	ID	Position in sequence	Description	Type
  PF00180	Iso_dh	50 → 376	Isocitrate/isopropylmalate dehydrogenase	Domain

• Sequence:

  MAALSGVRWLTRALVSAGNPGAWRGLSTSAAAHAASRSQAEDVRVEGSFPVTMLPGDGVG
  PELMHAVKEVFKAAAVPVEFQEHHLSEVQNMASEEKLEQVLSSMKENKVAIIGKIHTPME
  YKGELASYDMRLRRKLDLFANVVHVKSLPGYMTRHNNLDLVIIREQTEGEYSSLEHESAR
  GVIECLKIVTRAKSQRIAKFAFDYATKKGRGKVTAVHKANIMKLGDGLFLQCCEEVAELY
  PKIKFETMIIDNCCMQLVQNPYQFDVLVMPNLYGNIIDNLAAGLVGGAGVVPGESYSAEY
  AVFETGARHPFAQAVGRNIANPTAMLLSASNMLRHLNLEYHSSMIADAVKKVIKVGKVRT
  RDMGGYSTTTDFIKSVIGHLQTKGS

• Sequence length: 385