1. says

    A class of small RNAs (ca. 70-100 nt) called “guide RNAs” (gRNAs) directs posttranscriptional RNA editing in kinetoplastid mitochondria. The term “guide RNA” also refers to other types of RNA, such as the snoRNAs that guide pseudouridine formation in rRNA.

  2. Niles.Donegan@Dartmouth.EDU says

    Don’t forget tmRNA! They put tags on the mRNA in stalle ribosomes so that the nacent truncated protein has a shorter half-life.

  3. T_U_T says

    I wonder why someone bothers to mark function of a RNA piece by adding small letters before ‘RNA’… especially if we don’t do it with other molecules – we do not write trDNA for DNA that encodes a transposon, we don’t write enzymes involved in DNA repair as repenzymes, etc… So, why tRNA or other __RNA ?

  4. says

    I first got interested in genetics though a column on transcription and whatnot by Douglas Hofstadter. I still use, as a mnemonic device, the image he conjured of the ambassador Mr. Na and his interpreter Meri Boso.

  5. Loren Petrich says

    The next question is — why are there many functions of RNA but only one function of DNA?

    This can be interpreted as evidence of a former RNA world, a world where genomes were RNA and there was no DNA. Also consistent with the RNA-world hypothesis is the fact that organisms make DNA nucleotides from RNA ones instead of vice versa, as if DNA was a latecomer.

    This does not say anything about the evolution of protein synthesis; the first proteins could be older than DNA, or even RNA. So that question must be addressed separately.