Related Experiment Videos
Mouse cytoplasmic polyadenylylation element binding protein: an evolutionarily conserved protein that interacts with
1Worcester Foundation for Biomedical Research, Shrewsbury, MA 01545, USA.
Abstract:
Cytoplasmic polyadenylylation is an essential process that controls the translation of maternal mRNAs during early development and depends on two cis elements in the 3' untranslated region: the polyadenylylation hexanucleotide AAUAAA and a U-rich cytoplasmic polyadenylylation element (CPE). In searching for factors that could mediate cytoplasmic polyadenylylation of mouse c-mos mRNA, which encodes a serine/threonine kinase necessary for oocyte maturation, we have isolated the mouse homolog of CPEB, a protein that binds to the CPEs of a number of mRNAs in Xenopus oocytes and is required for their polyadenylylation. Mouse CPEB (mCPEB) is a 62-kDa protein that binds to the CPEs of c-mos mRNA. mCPEB mRNA is present in the ovary, testis, and kidney; within the ovary, this RNA is restricted to oocytes. mCPEB shows 80% overall identity with its Xenopus counterpart, with a higher homology in the carboxyl-terminal portion, which contains two RNA recognition motifs and a cysteine/histidine repeat. Proteins from arthropods and nematodes are also similar to this region, suggesting an ancient and widely used mechanism to control polyadenylylation and translation.
Insights
Researchers identified mouse CPEB (mCPEB), a protein crucial for cytoplasmic polyadenylylation and maternal mRNA translation during early development. This finding reveals an ancient mechanism regulating gene expression in oocytes and beyond.
Area of Science:
- Molecular Biology
- Developmental Biology
- Genetics
Background:
- Cytoplasmic polyadenylylation controls maternal mRNA translation during early development.
- This process relies on specific RNA elements like the AAUAAA hexanucleotide and cytoplasmic polyadenylylation elements (CPEs).
Purpose of the Study:
- To identify factors mediating cytoplasmic polyadenylylation of mouse c-mos mRNA.
- To investigate the role of the identified factor in oocyte maturation and gene expression.
Main Methods:
- Isolation and characterization of mouse CPEB (mCPEB).
- Analysis of mCPEB binding to c-mos mRNA CPEs.
- Examination of mCPEB mRNA distribution in mouse tissues.
Main Results:
- Mouse CPEB (mCPEB), a homolog of Xenopus CPEB, was isolated.
- mCPEB binds to the CPEs of mouse c-mos mRNA.
- mCPEB mRNA is found in ovaries, testes, and kidneys, specifically in oocytes within the ovary.
- mCPEB shares high homology with its Xenopus counterpart, particularly in RNA-binding domains.
Conclusions:
- mCPEB is a key mediator of cytoplasmic polyadenylylation for c-mos mRNA.
- The findings suggest an evolutionarily conserved mechanism for regulating polyadenylylation and translation.
- mCPEB plays a vital role in oocyte maturation and early development through translational control.