Mitochondrial RNA Import in Leishmania tropica: Aptamers Homologous to Multiple tRNA Domains That Interact Cooperatively or Antagonistically at the Inner Membrane
IR@IICB: CSIR-Indian Institute of Chemical Biology, Kolkata
View Archive Info| Field | Value | |
| Title |
Mitochondrial RNA Import in Leishmania tropica: Aptamers
Homologous to Multiple tRNA Domains That Interact Cooperatively
or Antagonistically at the Inner Membrane
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| Creator |
Bhattacharyya, Suvendra Nath
Chatterjee, Saibal Adhya, Samit |
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| Subject |
Molecular & Human Genetics
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| Description |
A large number of cytoplasmic tRNAs are imported into the kinetoplast-mitochondrion of Leishmania by a
receptor-mediated process. To identify the sequences recognized by import receptors, mitochondria were
incubated with a combinatorial RNA library. Repeated cycles of amplification of the imported sequences
(SELEX) resulted in rapid selection of several import aptamers containing sequence motifs present in the
anticodon arm, the D arm, the V-T region, and acceptor stem of known tRNAs, confirming or suggesting the
presence of import signals in these domains. As predicted, truncated derivatives of tRNAIle(UAU) containing
the D arm or the V-T region were imported in vitro. Four aptamers were studied in detail. All were imported
in vitro as well as in transiently transfected cells, using the same pathway as tRNA, but their individual import
efficiencies were different. Two types of aptamers were discernible: the A arm and D arm homologues (type I),
which were efficiently transferred across the inner mitochondrial membrane, and the V-T homologues (type II),
which were not. Remarkably, subnanomolar concentrations of type I RNAs stimulated the entry of type II
RNAs into the matrix, whereas type II RNAs inhibited inner membrane transfer of type I RNAs. Moreover,
tRNATyr(GUA) and tRNAIle(UAU) interacted with one another as type I and type II, respectively. Such cooperative
and antagonistic interactions may allow the use of a limited number of receptors to recognize a large
number of tRNAs of variable affinity and enable the maintenance of a properly balanced tRNA pool for mitochondrial
translation.
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| Publisher |
American Society for Microbiology
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| Date |
2002
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| Type |
Article
PeerReviewed |
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| Format |
application/pdf
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| Identifier |
http://www.eprints.iicb.res.in/774/1/MOLECULAR_AND_CELLULAR_BIOLOGY___22_(12)_4372%2D4382;2002[53].pdf
Bhattacharyya, Suvendra Nath and Chatterjee, Saibal and Adhya, Samit (2002) Mitochondrial RNA Import in Leishmania tropica: Aptamers Homologous to Multiple tRNA Domains That Interact Cooperatively or Antagonistically at the Inner Membrane. Molecular and Cellular Biology, 22 (12). pp. 4372-4382. |
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| Relation |
http://dx.doi.org/10.1128/MCB.22.12.4372–4382.2002
http://www.eprints.iicb.res.in/774/ |
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