InnateDB: Systems Biology of the Innate Immune Response

Homo sapiens Protein: PHAX

Summary

InnateDB Protein

IDBP-39426.6

Last Modified

2014-10-13 [Report errors or provide feedback]

Gene Symbol

PHAX

Protein Name

phosphorylated adaptor for RNA export

Synonyms

Species

Homo sapiens

Ensembl Protein

ENSP00000297540

InnateDB Gene

IDBG-39424 (PHAX)

Protein Structure

UniProt Annotation

Function

A phosphoprotein adapter involved in the XPO1-mediated U snRNA export from the nucleus. Bridge components required for U snRNA export, the cap binding complex (CBC)-bound snRNA on the one hand and the GTPase Ran in its active GTP-bound form together with the export receptor XPO1 on the other. Its phosphorylation in the nucleus is required for U snRNA export complex assembly and export, while its dephosphorylation in the cytoplasm causes export complex disassembly. It is recycled back to the nucleus via the importin alpha/beta heterodimeric import receptor. The directionality of nuclear export is thought to be conferred by an asymmetric distribution of the GTP- and GDP-bound forms of Ran between the cytoplasm and nucleus. Its compartmentalized phosphorylation cycle may also contribute to the directionality of export. Binds strongly to m7G-capped U1 and U5 small nuclear RNAs (snRNAs) in a sequence-unspecific manner and phosphorylation- independent manner (By similarity). Plays also a role in the biogenesis of U3 small nucleolar RNA (snoRNA). Involved in the U3 snoRNA transport from nucleoplasm to Cajal bodies. Binds strongly to m7G-capped U3, U8 and U13 precursor snoRNAs and weakly to trimethylated (TMG)-capped U3, U8 and U13 snoRNAs. Binds also to telomerase RNA. {ECO:0000250, ECO:0000269PubMed:15574332, ECO:0000269PubMed:15574333}.

Subcellular Localization

Nucleus, nucleoplasm. Nucleus, Cajal body. Cytoplasm. Note=Located in the nucleoplasm and Cajal bodies. Shuttles between the nucleus and the cytoplasm. Shuttles between the nucleoplasm and Cajal bodies.

Disease Associations

Tissue Specificity

Comments

Interactions

Number of Interactions

This gene and/or its encoded proteins are associated with 38 experimentally validated interaction(s) in this database.

Experimentally validated
Total	38 [view]
Protein-Protein	38 [view]
Protein-DNA	0
Protein-RNA	0
DNA-DNA	0
RNA-RNA	0
DNA-RNA	0

Gene Ontology

Molecular Function

Accession	GO Term
GO:0003723	RNA binding
GO:0015643	toxic substance binding

Biological Process

GO:0000387	spliceosomal snRNP assembly
GO:0006408	snRNA export from nucleus
GO:0010467	gene expression
GO:0015031	protein transport
GO:0016070	RNA metabolic process
GO:0034660	ncRNA metabolic process

Cellular Component

GO:0005634	nucleus
GO:0005654	nucleoplasm
GO:0005730	nucleolus
GO:0005737	cytoplasm
GO:0005829	cytosol
GO:0015030	Cajal body
GO:0043025	neuronal cell body
GO:0043231	intracellular membrane-bounded organelle