Differential expression in male and female mouse liver of very similar mRNAs specified by two group 1 major urinary protein genes.

Abstract

The major urinary proteins of the mouse are encoded by a large multigene family composed of several distinct groups of genes distinguished by differences in sequence and expression characteristics. The genes in the largest group (group 1) show greater than 99% pairwise similarity in their exons. By hybridization between RNA and a specifically designed oligonucleotide, we confirmed that genes of this group are expressed mainly in the liver. By using additional gene-specific oligonucleotide probes, we have been able to distinguish between the species of mRNA corresponding to two of these genes and to measure their abundance in male and female liver. Both mRNAs are present in male liver at high but different levels. Both are also present in female liver, one at a much lower level than in the male and the second at a very low level indeed. Both are present at male levels in the livers of females induced with testosterone. These results show unequivocally that the expression of different group 1 Mup genes is differentially influenced by the hormonal status of the mouse.

Central Dopamine D2 Receptors Regulate Growth-Hormone-Dependent Body Growth and Pheromone Signaling to Conspecific Males

“…The lower serum levels of IGF-I observed in neuroDrd2KO mice are consistent with their smaller body size and weight, a phenotype that in the wild could be detrimental for reproductive fitness due to reduced competitiveness among males. The sexually dimorphic liver proteins that depend on the male pattern of GH release is manifold and include MUPs (McIntosh and Bishop, 1989). This group of pheromones secreted into the blood and then excreted in the urine are known to promote social recognition and territorial dominance between males (Hurst et al, 2001;Chamero et al, 2007).…”

Male-specific expression of mouse sex-limited protein requires growth hormone, not testosterone.

“…Although other sexually differentiated hepatic transcripts have been shown to be regulated in the mouse by the difference in GH-release pattern, the dependence on the mode of GH administration is either partial (34,35) or more complex (14,26) than in the case of C4/C4-Slp. In our opinion, the genetic complexity of the other systems in contrast to C4/C4-Slp must be responsible for the incomplete down-regulation of Mup by GH (35), for the peculiar multihormonal regulation (i.e., by estrogens, thyroid, and glucorticoid hormones) of the P-450 II family (reviewed in ref.…”

“…As in other mammals, C4 is produced both in liver and in macrophages, but only hepatocytes synthesize Slp. Even though other hepatic genes that display sexually dimorphic regulation have been more intensively studied (9, 10), the C4/C4-Slp system is notable for its more pronounced testosterone response, the array of available regulation variants (11), and lack of the genetic and functional complexity seen in multigene families such as the androgen-inducible a2u globulin in the rat (12) and the homologous mouse major urinary protein (Mup) (13,14). The system acquires additional interest by the existence of trans-acting mutations (15, 37) that override the testosterone requirement of the C4-Slp gene.…”

Major Urinary Protein-1 Increases Energy Expenditure and Improves Glucose Intolerance through Enhancing Mitochondrial Function in Skeletal Muscle of Diabetic Mice

“…We found that the mRNA level of mouse major urinary protein-1 (MUP-1) 2 was markedly down-regulated in db/db mice, and the change was largely normalized upon treatment with the PPAR␥ agonist rosiglitazone. MUP-1 is a small molecular weight secreted protein abundantly expressed in the liver (14). Its expression in the liver is enhanced by administration of the hepatotoxic agent dimethylnitrosamine (15) …”