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Luzp4 defines a new mRNA export pathway in cancer cells.

ABSTRACT: Cancer testis antigens (CTAs) represented a poorly characterized group of proteins whose expression is normally restricted to testis but are frequently up-regulated in cancer cells. Here we show that one CTA, Luzp4, is an mRNA export adaptor. It associates with the TREX mRNA export complex subunit Uap56 and harbours a Uap56 binding motif, conserved in other mRNA export adaptors. Luzp4 binds the principal mRNA export receptor Nxf1, enhances its RNA binding activity and complements Alyref knockdown in vivo. Whilst Luzp4 is up-regulated in a range of tumours, it appears preferentially expressed in melanoma cells where it is required for growth.

SUBMITTER: Viphakone N

PROVIDER: S-EPMC4344508 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Luzp4 defines a new mRNA export pathway in cancer cells.

Viphakone Nicolas N Cumberbatch Marcus G MG Livingstone Michaela J MJ Heath Paul R PR Dickman Mark J MJ Catto James W JW Wilson Stuart A SA

Nucleic acids research 20150206 4

Cancer testis antigens (CTAs) represented a poorly characterized group of proteins whose expression is normally restricted to testis but are frequently up-regulated in cancer cells. Here we show that one CTA, Luzp4, is an mRNA export adaptor. It associates with the TREX mRNA export complex subunit Uap56 and harbours a Uap56 binding motif, conserved in other mRNA export adaptors. Luzp4 binds the principal mRNA export receptor Nxf1, enhances its RNA binding activity and complements Alyref knockdow ...[more]

PMID: 25662211

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