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Methods to Discover Alternative Promoter Usage and Transcriptional Regulation of Murine Bcrp1
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Methods to Discover Alternative Promoter Usage and Transcriptional Regulation of Murine Bcrp1

Published on: May 27, 2016

Variation in the polyadenylylation site of bovine prolactin mRNA

N L Sasavage, M Smith, S Gillam

    Proceedings of the National Academy of Sciences of the United States of America
    |January 1, 1982
    PubMed

    Insights

    Bovine prolactin (bPRL) mRNA exhibits multiple polyadenylation sites, leading to variations in mRNA length. This heterogeneity in 3' end processing was confirmed through cDNA synthesis and sequencing.

    Area of Science:

    • Molecular Biology
    • Genetics
    • Biochemistry

    Background:

    • Messenger RNA (mRNA) molecules undergo post-transcriptional modifications, including polyadenylation, which is crucial for stability and translation.
    • The 3' end of mRNA, specifically the polyadenylation site, can exhibit variability, influencing mRNA characteristics.

    Purpose of the Study:

    • To investigate the polyadenylation site of bovine prolactin (bPRL) mRNA.
    • To determine if multiple polyadenylation sites exist in bPRL mRNA and characterize the resulting heterogeneity.

    Main Methods:

    • Phased priming of complementary DNA (cDNA) synthesis using specific oligodeoxynucleotides.
    • Analysis of chain-termination fragments generated during cDNA synthesis.
    • Nucleotide sequencing of bPRL cDNA clones.

    Main Results:

    • Evidence of multiple poly(A)-adjacent sequences in bPRL mRNA was found, indicated by specific chain-termination fragments.
    • Sequence analysis revealed that variations in bPRL mRNA length occurred within a 12-nucleotide span.
    • Identical nucleotide sequences for the 3' noncoding region were observed across different bPRL mRNA species, suggesting length heterogeneity.
    • Multiple poly(A) sites were confirmed, with heterogeneous mRNA molecules present in pituitary gland samples.

    Conclusions:

    • Bovine prolactin mRNA possesses multiple polyadenylation sites, resulting in heterogeneous mRNA lengths.
    • This variation in poly(A) junction likely reflects processing events at the 3' terminus of mRNA.
    • Understanding mRNA processing is vital for comprehending gene expression regulation.

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