Messenger RNAs coding for mouse major urinary proteins are differentially induced by testosterone

Area of Science:

• Biochemistry
• Genetics
• Molecular Biology

Background:

• Major urinary proteins (MUPs) are a family of small secreted proteins found in mouse urine.
• MUPs play roles in pheromonal communication and social behavior.
• Sexual dimorphism in MUP expression has been observed, but the underlying genetic and hormonal mechanisms are not fully understood.

Purpose of the Study:

• To investigate the sexual dimorphism of mouse major urinary proteins (MUPs).
• To determine the influence of testosterone on MUP expression patterns.
• To explore the transcriptional regulation of MUP genes in male and female mice.

Main Methods:

• Isoelectric focusing (IEF) was used to analyze MUP protein patterns in different inbred mouse strains.
• In vitro translation of hybrid-selected MUP messenger RNA (mRNA) was performed.
• Effects of testosterone treatment on MUP excretion and mRNA patterns were examined.

Main Results:

• Female mice exhibited simpler MUP patterns compared to males, with strain-specific differences in the main female component.
• Testosterone treatment in females induced MUP patterns resembling those of males.
• Analysis of MUP mRNA revealed simpler patterns in females, which shifted towards male patterns after testosterone administration.

Conclusions:

• Mouse MUP expression displays significant sexual dimorphism, influenced by hormonal regulation.
• Some MUP structural genes are actively transcribed in females, while others require testosterone induction.
• Testosterone plays a crucial role in regulating the transcription of specific MUP genes, contributing to the observed sexual dimorphism.