Related Experiment Videos
Cloning and sequence analysis of cDNA for mouse prolactin
Biochimica Et Biophysica Acta
|October 16, 1986
Summary
Mouse prolactin mRNA shows no sexual differences, despite variations in signal peptides. This finding suggests that differences in biological activity are not due to distinct messenger RNA sequences in males and females.
Area of Science:
- Molecular Biology
- Endocrinology
- Genetics
Background:
- Sexual dimorphism in mouse prolactin's biological activity and amino acid composition has been observed.
- The underlying cause for these differences, particularly potential mRNA heterogeneity, requires investigation.
Purpose of the Study:
- To determine if sexual dimorphism in mouse prolactin is caused by variations in messenger RNA (mRNA).
- To analyze the nucleotide and amino acid sequences of mouse prolactin and identify any sex-specific differences.
Main Methods:
- Cloning of mouse prolactin cDNAs from a pituitary cDNA library using rat prolactin cDNA as a probe.
- Nucleotide sequence analysis of cloned cDNAs to determine the amino acid sequence of the prolactin precursor.
- S1 nuclease mapping analysis of male and female pituitary RNAs to assess mRNA structure.
Main Results:
- A nearly full-length cDNA sequence for mouse prolactin precursor was obtained, revealing a signal peptide and prolactin sequence with minor differences from previous reports.
- Analysis indicated that mouse preprolactin is encoded by two distinct mRNAs in both sexes.
- These two mRNAs differ by a three-nucleotide deletion in the signal peptide coding region.
- Crucially, no sexual difference was found in the murine prolactin mRNA itself.
Conclusions:
- The heterogeneity in mouse prolactin mRNA, specifically the presence of two forms differing in the signal peptide region, exists in both male and female mice.
- The observed sexual dimorphism in biological activities and amino acid composition of mouse prolactin is not attributable to differences in prolactin mRNA sequences between sexes.