An Abundant Class of Tiny RNAs with Probable Regulatory Roles in Caenorhabditis elegans

• Published in: Science (American Association for the Advancement of Science) Vol. 294; no. 5543; pp. 858 - 862
• Main Authors: Lau, Nelson C., Lim, Lee P., Weinstein, Earl G., Bartel, David P.
• Format: Journal Article
• Language: English
• Published: Washington, DC American Society for the Advancement of Science 26.10.2001; American Association for the Advancement of Science; The American Association for the Advancement of Science
• Subjects: Algorithms; Animals; Base Sequence; Biological and medical sciences; Blotting, Northern; Caenorhabditis elegans; Caenorhabditis elegans - genetics; Cellular biology; Cloning, Molecular; Coding; Conserved Sequence; Developmental Stages; Drosophila; Endoribonucleases - metabolism; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation; Gene Expression Regulation, Developmental; Genes; Genes, Helminth; Genome; Genomics; Humans; Introns; Messenger RNA; MicroRNA; miRNA; Molecular and cellular biology; Molecular Sequence Data; Multigene Family; Nucleic Acid Conformation; nucleotides; Ribonuclease III; Ribonucleic acid; RNA; RNA Precursors - genetics; RNA Precursors - metabolism; RNA, Helminth - chemistry; RNA, Helminth - genetics; RNA, Helminth - physiology; RNA, Untranslated - chemistry; RNA, Untranslated - genetics; RNA, Untranslated - physiology; Small interfering RNA; stRNA; Transcription, Genetic; Transcripts (Written Records); Untranslated regions; Young Adults
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1065062

Two small temporal RNAs (stRNAs), lin-4 and let-7, control developmental timing in Caenorhabditis elegans. We find that these two regulatory RNAs are members of a large class of 21- to 24-nucleotide noncoding RNAs, called microRNAs (miRNAs). We report on 55 previously unknown miRNAs in C. elegans. The miRNAs have diverse expression patterns during development: a let-7 paralog is temporally coexpressed with let-7; miRNAs encoded in a single genomic cluster are coexpressed during embryogenesis; and still other miRNAs are expressed constitutively throughout development. Potential orthologs of several of these miRNA genes were identified in Drosophila and human genomes. The abundance of these tiny RNAs, their expression patterns, and their evolutionary conservation imply that, as a class, miRNAs have broad regulatory functions in animals.