Characterization of the cis-acting element directing perinuclear localization of the metallothionein-1 mRNA
Subcellular localization of mRNAs is a key mechanism for the synthesis of proteins close to their site of function. The mRNA encoding MT-1 (metallothionein-1) is localized in the perinuclear cytoplasm, where it is associated with cytoskeletal-bound polysomes. This localization relies on sequences pr...
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Published in | Biochemical Society transactions Vol. 32; no. Pt 5; p. 702 |
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Main Authors | , , , , |
Format | Journal Article |
Language | English |
Published |
England
01.11.2004
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Subjects | |
Online Access | Get more information |
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Summary: | Subcellular localization of mRNAs is a key mechanism for the synthesis of proteins close to their site of function. The mRNA encoding MT-1 (metallothionein-1) is localized in the perinuclear cytoplasm, where it is associated with cytoskeletal-bound polysomes. This localization relies on sequences present in the 3'-UTR (3'-untranslated region). The present study aims to characterize the cis-acting localization element(s) within the 3'-UTR. Using transfected cells expressing tagged MT-1 differing in their 3'-UTRs (deleted or mutated), the section(s) of this region required for directing MT-1 transcripts to the perinuclear cytoplasm has been investigated. Different 3'-UTRs were also used in UV cross-linking experiments that highlighted two distinct regions (nt 26-30 and 66-76) necessary for the binding of a protein of approx. 50 kDa, presumably involved in the mRNA targeting. The poor sequence homology between the MT-1 3'-UTR of various species, together with the bipartite nature of the required cis-element, indicates the involvement of a particular structure in the localization signal. The secondary structure of the MT-1 3'-UTR was investigated using enzymic and chemical probing. Current structural analysis of mutant 3'-UTRs will allow the critical structural features of the MT-1 mRNA perinuclear localization signal to be defined. |
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ISSN: | 0300-5127 |
DOI: | 10.1042/BST0320702 |