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An X chromosome microRNA cluster in the marsupial species Monodelphis domestica.

ABSTRACT: MicroRNAs (miRNAs) are an important class of posttranscriptional gene expression regulators. In the course of mapping novel marsupial-specific miRNAs in the genome of the gray short-tailed opossum, Monodelphis domestica, we encountered a cluster of 39 actual and potential miRNAs spanning 102 kb of the X chromosome. Analysis of the cluster revealed that 37 of the 39 miRNAs are predicted to form thermodynamically stable hairpins, and at least 3 members have been directly cloned from M. domestica tissues. The sequence characteristics of these miRNAs suggest that they all descended from a single common ancestor. Further, 2 distinct families appear to have diversified from the ancestral sequence through different duplication mechanisms: one through a series of simple tandem duplications and the other through a recurrent transposon-mediated duplication process.

SUBMITTER: Devor EJ

PROVIDER: S-EPMC3156565 | biostudies-literature | 2011 Sep-Oct

REPOSITORIES: biostudies-literature

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An X chromosome microRNA cluster in the marsupial species Monodelphis domestica.

Devor Eric J EJ Huang Lingyan L Wise Amanda A Peek Andrew S AS Samollow Paul B PB

The Journal of heredity 20110617 5

MicroRNAs (miRNAs) are an important class of posttranscriptional gene expression regulators. In the course of mapping novel marsupial-specific miRNAs in the genome of the gray short-tailed opossum, Monodelphis domestica, we encountered a cluster of 39 actual and potential miRNAs spanning 102 kb of the X chromosome. Analysis of the cluster revealed that 37 of the 39 miRNAs are predicted to form thermodynamically stable hairpins, and at least 3 members have been directly cloned from M. domestica t ...[more]

PMID: 21685406

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