Search Results

Overview

Uniprot ID	Q13838
Protein Name	Spliceosome RNA helicase DDX39B
Gene Name	DDX39B
Organism	Homo sapiens

Kla Sites from experimental identification

Position	Flanking peptide
183	ILALARNKSLNLKHI
188	RNKSLNLKHIKHFIL
191	SLNLKHIKHFILDEC
334	LSRYQQFKDFQRRIL
36	APAKKDVKGSYVSIH

Function

Involved in nuclear export of spliced and unspliced mRNA (PubMed:15833825, PubMed:15998806, PubMed:17190602). Component of the TREX complex which is thought to couple mRNA transcription, processing and nuclear export, and specifically associates with spliced mRNA and not with unspliced pre-mRNA (PubMed:15833825, PubMed:15998806, PubMed:17190602). The TREX complex is recruited to spliced mRNAs by a transcription-independent mechanism, binds to mRNA upstream of the exon-junction complex (EJC) and is recruited in a splicing- and cap-dependent manner to a region near the 5' end of the mRNA where it functions in mRNA export to the cytoplasm via the TAP/NXF1 pathway (PubMed:15833825, PubMed:15998806, PubMed:17190602). The THOC1-THOC2-THOC3 core complex alone is sufficient to promote ATPase activity of DDX39B; in the complex THOC2 is the only component that directly interacts with DDX39B (PubMed:33191911). Associates with SARNP/CIP29, which facilitates RNA binding of DDX39B and likely plays a role in mRNA export (PubMed:37578863). May undergo several rounds of ATP hydrolysis during assembly of TREX to drive subsequent loading of components such as ALYREF/THOC4 and CHTOP onto mRNA. Also associates with pre-mRNA independent of ALYREF/THOC4. Involved in the nuclear export of intronless mRNA; the ATP-bound form is proposed to recruit export adapter ALYREF/THOC4 to intronless mRNA; its ATPase activity is cooperatively stimulated by RNA and ALYREF/THOC4 and ATP hydrolysis is thought to trigger the dissociation from RNA to allow the association of ALYREF/THOC4 and the NXF1-NXT1 heterodimer. Involved in transcription elongation and genome stability

Protein Sequence

10 MAENDVDNEL 20 LDYEDDEVET 30 AAGGDGAEAP 40 AKKDVKGSYV 50 SIHSSGFRDF 60 LLKPELLRAI 70 VDCGFEHPSE 80 VQHECIPQAI 90 LGMDVLCQAK 100 SGMGKTAVFV 110 LATLQQLEPV 120 TGQVSVLVMC 130 HTRELAFQIS 140 KEYERFSKYM 150 PNVKVAVFFG 160 GLSIKKDEEV 170 LKKNCPHIVV 180 GTPGRILALA 190 RNKSLNLKHI 200 KHFILDECDK 210 MLEQLDMRRD 220 VQEIFRMTPH 230 EKQVMMFSAT 240 LSKEIRPVCR 250 KFMQDPMEIF 260 VDDETKLTLH 270 GLQQYYVKLK 280 DNEKNRKLFD 290 LLDVLEFNQV 300 VIFVKSVQRC 310 IALAQLLVEQ 320 NFPAIAIHRG 330 MPQEERLSRY 340 QQFKDFQRRI 350 LVATNLFGRG 360 MDIERVNIAF 370 NYDMPEDSDT 380 YLHRVARAGR 390 FGTKGLAITF 400 VSDENDAKIL 410 NDVQDRFEVN 420 ISELPDEIDI SSYIEQTR

Gene Ontology

Classification	GO ID	Description
Cellular Component	GO:0005737	cytoplasm
Cellular Component	GO:0016607	nuclear speck
Cellular Component	GO:0005654	nucleoplasm
Cellular Component	GO:0005634	nucleus
Cellular Component	GO:0005681	spliceosomal complex
Cellular Component	GO:0000346	transcription export complex
Cellular Component	GO:0005687	U4 snRNP
Cellular Component	GO:0005688	U6 snRNP
Molecular Function	GO:0005524	ATP binding
Molecular Function	GO:0016887	ATP hydrolysis activity
Molecular Function	GO:0008186	ATP-dependent activity, acting on RNA
Molecular Function	GO:0043008	ATP-dependent protein binding
Molecular Function	GO:0042802	identical protein binding
Molecular Function	GO:0003729	mRNA binding
Molecular Function	GO:0003723	RNA binding
Molecular Function	GO:0003724	RNA helicase activity
Molecular Function	GO:0030621	U4 snRNA binding
Molecular Function	GO:0017070	U6 snRNA binding
Biological Process	GO:0006406	mRNA export from nucleus
Biological Process	GO:0000398	mRNA splicing, via spliceosome
Biological Process	GO:0006405	RNA export from nucleus
Biological Process	GO:0008380	RNA splicing
Biological Process	GO:0000245	spliceosomal complex assembly

Reference

[1] Yang D, Yin J, Shan L, Yi X, Zhang W et al.. Identification of lysine-lactylated substrates in gastric cancer cells.. iScience 25(7):104630. 2022 Jul 15. PMID: 35800753.

[2] Yang Z, Yan C, Ma J, Peng P, Ren X et al.. Lactylome analysis suggests lactylation-dependent mechanisms of metabolic adaptation in hepatocellular carcinoma.. Nat Metab 5(1):61-79. 2023 Jan. PMID: 36593272.

[3] Hong H, Chen X, Wang H, Gu X, Yuan Y et al.. Global profiling of protein lysine lactylation and potential target modified protein analysis in hepatocellular carcinoma.. Proteomics 23(9):e2200432. 2023 May. PMID: 36625413.

[4] He C, Zhang J, Bai X, Lu C, Zhang K. Lysine lactylation-based insight to understanding the characterization of cervical cancer.. Biochim Biophys Acta Mol Basis Dis 1870(7):167356. 2024 Oct. PMID: 39025375.

[5] Bao Q, Wan N, He Z, Cao J, Yuan W et al.. Subcellular Proteomic Mapping of Lysine Lactylation.. J Am Soc Mass Spectrom 35(12):3221-3232. 2024 Dec 4. PMID: 39569522.

[6] Shi CM, Wang QC, Li XL, Yang YH, Tang XY et al.. Global Profiling of Protein Lactylation in Human Hippocampi.. Proteomics Clin Appl 19(2):e202400061. 2025 Mar. PMID: 39610256.

[7] Guo X, Ren X, Yan C, Huang H. Quantitative Proteomics Reveals the Role of Lysine Lactylation in Lenalidomide-Resistance in Multiple Myeloma Cells.. ACS Chem Biol 20(7):1728-1738. 2025 Jul 18. PMID: 40590393.

[8] He J, Lai T, Zhou Z, Yang H, Lei Z et al.. Multiomics profiling reveals the involvement of protein lactylation in nonhomologous end joining pathway conferring radioresistance in lung adenocarcinoma cell.. Sci Rep 15(1):24651. 2025 Jul 9. PMID: 40634431.

[9] Wu Q, Li Z, Gong T, Zheng X, Zhou X et al.. Porphyromonas gingivalis infection induces lysine lactylation reprogramming in human umbilical vein endothelial cells.. Front Cell Infect Microbiol 16:1706727. 2026. PMID: 41696360.