Abstract |
HuD is one of a family of neural antigens recognised by the sera of patients with antibody-associated paraneoplastic encephalomyelitis. Localised exclusively to neurons, these proteins are among the earliest markers of the developing nervous system. Sequence analysis suggests that HuD is an RNA-binding protein. Hu protein levels were determined for the three cell types characterising human neuroblastoma cell lines: sympathoadrenal neuroblasts (N), substrate-adherent Schwann/glial/melanoblastic precursors (S) and stem cells (I) which can give rise to both N and S cells. Western blot analysis showed similar levels of protein in three N-type cell lines; S cells have no detectable Hu protein. Northern blot analysis indicated that N cells express all three Hu genes, HuD, HuC and Hel-N1. N cells, mostly from MYCN-amplified cell lines, have consistently higher steady-state levels of MYCN mRNA than S cell counterparts. Nuclear run-on and mRNA half-life experiments revealed no differences in transcription rate or mRNA stability between N and S cells from the LA-N-1 cell line, implicating differences in post-transcriptional regulation. HuD is postulated to be instrumental in splicing/processing and/or stabilisation of mRNAs involved in cell growth and neuronal differentiation. As determined by gel-mobility shift assays, HuD fusion protein binds to the 3'UTR of human MYCN mRNA. Analysis of HuD deletion mutants has demonstrated that the first and second RNA-recognition motifs (RRMs) are required for binding. Whether HuD regulates MYCN expression and thereby influences tumour aggressiveness is of major interest.
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Authors | R A Ross, D L Lazarova, G T Manley, P S Smitt, B A Spengler, J B Posner, J L Biedler |
Journal | European journal of cancer (Oxford, England : 1990)
(Eur J Cancer)
Vol. 33
Issue 12
Pg. 2071-4
(Oct 1997)
ISSN: 0959-8049 [Print] England |
PMID | 9516855
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- ELAV Proteins
- ELAV-Like Protein 4
- ELAVL4 protein, human
- Neoplasm Proteins
- Nerve Tissue Proteins
- Proto-Oncogene Proteins c-myc
- RNA, Messenger
- RNA-Binding Proteins
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Topics |
- Binding Sites
- Blotting, Northern
- ELAV Proteins
- ELAV-Like Protein 4
- Humans
- Neoplasm Proteins
(genetics, metabolism, physiology)
- Nerve Tissue Proteins
- Neuroblastoma
(metabolism, pathology)
- Protein Binding
- Proto-Oncogene Proteins c-myc
(genetics, metabolism, physiology)
- RNA, Messenger
(metabolism)
- RNA-Binding Proteins
(genetics, metabolism, physiology)
- Sequence Deletion
- Tumor Cells, Cultured
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