Related Experiment Video

Updated: Aug 19, 2026

Visualizing RNA Localization in Xenopus Oocytes
07:06

Visualizing RNA Localization in Xenopus Oocytes

Published on: January 14, 2010

Identification of multiple RNases in Xenopus laevis oocytes and their possible role in tRNA processing

A Solari, M P Deutscher

    Molecular and Cellular Biology
    |October 1, 1983
    PubMed

    Insights

    Researchers surveyed Xenopus laevis oocytes for RNases involved in tRNA processing. Multiple RNase activities were identified, including cytoplasmic and nuclear enzymes crucial for generating tRNA precursors.

    Area of Science:

    • Molecular Biology
    • Biochemistry
    • Developmental Biology

    Background:

    • Transfer RNA (tRNA) is essential for protein synthesis, requiring precise processing.
    • Xenopus laevis oocytes are a valuable model system for studying early developmental processes and gene expression.

    Purpose of the Study:

    • To identify and characterize RNase enzymes in Xenopus laevis oocytes involved in tRNA processing.
    • To understand the specific roles of different RNase activities in the maturation of tRNA.

    Main Methods:

    • Survey of RNase activities in Xenopus laevis oocytes using various specific and nonspecific substrates.
    • Analysis of cleavage products from an artificial tRNA precursor (tRNA-C-[14C]U-C).
    • Distinguishing between cytoplasmic exonuclease and nuclear endonuclease activities.

    Main Results:

    • Multiple RNases with diverse specificities were detected in Xenopus laevis oocytes.
    • Three key RNase activities capable of processing the artificial tRNA precursor were identified.
    • A cytoplasmic exonuclease produced tRNA-C, while two nuclear endonucleases generated tRNA-N.

    Conclusions:

    • Xenopus laevis oocytes possess multiple RNase activities essential for tRNA 3' end processing.
    • Distinct cytoplasmic and nuclear RNases play specific roles in preparing tRNA for CCA addition.

    More Related Videos

    Production of Xenopus tropicalis Egg Extracts to Identify Microtubule-associated RNAs10:01

    Production of Xenopus tropicalis Egg Extracts to Identify Microtubule-associated RNAs

    Published on: June 27, 2013

    Xenopus laevis as a Model to Identify Translation Impairment10:24

    Xenopus laevis as a Model to Identify Translation Impairment

    Published on: September 27, 2015

    Related Concept Videos

    RNA Splicing01:32

    RNA Splicing

    Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
    Eukaryotic RNA Polymerases00:58

    Eukaryotic RNA Polymerases

    RNA Polymerase (RNAP) is conserved in all animals, with bacterial, archaeal, and eukaryotic RNAPs sharing significant sequence, structural, and functional similarities. Among the three eukaryotic RNAPs, RNA Polymerase II is most similar to bacterial RNAP in terms of both structural organization and folding topologies of the enzyme subunits. However, these similarities are not reflected in their mechanism of action.
    All three eukaryotic RNAPs require specific transcription factors, of which the...
    Chromatin Structure Regulates pre-mRNA Processing02:41

    Chromatin Structure Regulates pre-mRNA Processing

    In eukaryotic cells, nascent mRNA transcripts need to undergo many post-transcriptional modifications to reach the cell cytoplasm and translate into functional proteins. For a long time, transcription and pre-mRNA processing were considered two independent events that occur sequentially in the cell. However, it has now been well established that transcription and pre-mRNA processing are two simultaneous processes that are precisely regulated inside the cell.
    The chromatin structure, especially...
    Ribosomal RNA Synthesis02:53

    Ribosomal RNA Synthesis

    Ribosome synthesis is a highly complex and coordinated process involving more than 200 assembly factors. The synthesis and processing of ribosomal components occurs not only in the nucleolus but also in the nucleoplasm and the cytoplasm of eukaryotic cells.
    Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
    Transfer RNA Synthesis02:36

    Transfer RNA Synthesis

    One of the unique features of tRNA is the presence of modified bases. In some tRNAs, modified bases account for nearly 20% of the total bases in the molecule. Altogether, these unusual bases protect the tRNA from enzymatic degradation by RNases.
    Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
    Transcription Initiation01:47

    Transcription Initiation

    Initiation is the first step of transcription in eukaryotes. Prokaryotic RNA Polymerase (RNAP) can bind to the template DNA and start transcribing. On the other hand, transcription in eukaryotes requires additional proteins, called transcription factors, to first bind to the promoter region in the DNA template. This binding helps recruit the specific RNAP that can assemble on the DNA and start transcription.
    The promoters and enhancers and their accessory proteins allow tight regulation of...