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Genomic analysis of human microRNA transcripts.

ABSTRACT: MicroRNAs (miRNAs) are important genetic regulators of development, differentiation, growth, and metabolism. The mammalian genome encodes approximately 500 known miRNA genes. Approximately 50% are expressed from non-protein-coding transcripts, whereas the rest are located mostly in the introns of coding genes. Intronic miRNAs are generally transcribed coincidentally with their host genes. However, the nature of the primary transcript of intergenic miRNAs is largely unknown. We have performed a large-scale analysis of transcription start sites, polyadenylation signals, CpG islands, EST data, transcription factor-binding sites, and expression ditag data surrounding intergenic miRNAs in the human genome to improve our understanding of the structure of their primary transcripts. We show that a significant fraction of primary transcripts of intergenic miRNAs are 3-4 kb in length, with clearly defined 5' and 3' boundaries. We provide strong evidence for the complete transcript structure of a small number of human miRNAs.

SUBMITTER: Saini HK

PROVIDER: S-EPMC2077053 | biostudies-literature | 2007 Nov

REPOSITORIES: biostudies-literature

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Genomic analysis of human microRNA transcripts.

Saini Harpreet Kaur HK Griffiths-Jones Sam S Enright Anton James AJ

Proceedings of the National Academy of Sciences of the United States of America 20071026 45

MicroRNAs (miRNAs) are important genetic regulators of development, differentiation, growth, and metabolism. The mammalian genome encodes approximately 500 known miRNA genes. Approximately 50% are expressed from non-protein-coding transcripts, whereas the rest are located mostly in the introns of coding genes. Intronic miRNAs are generally transcribed coincidentally with their host genes. However, the nature of the primary transcript of intergenic miRNAs is largely unknown. We have performed a l ...[more]

PMID: 17965236

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Dataset Information

Genomic analysis of human microRNA transcripts.

Publications

Genomic analysis of human microRNA transcripts.

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