Wild mice

Individual mice express a combinatorial pattern of MUPs (typically at least 7-12 isoforms) reflecting multiple allelic variants and multiple expressed loci (Robertson et al. 1997). Among wild mice, individuals each express a different pattern even when captured from the same population (Payne, Malone, Humphries, Bradbrook, Veggerby, Beynon and Hurst 2001 Beynon et al. 2002), with the exception of very closely related animals that have inherited the same haplotypes from their parents (a 25% chance among outbred sibs, similar to MHC type sharing). The extreme heterogeneity in the sequence of MUPs is mostly confined to strands B, C and D and the intervening turns of the 8-barrel structure (Beynon et al. 2002). 

Krackow, S. and Matuschak, B. (1991) Mate choice for non-siblings in wild mice - evidence from a choice test and a reproductive test. Ethology 88, 99-108. 

Laboratory and domestic animals may be poor models for avoidance of predator odors. For example, in one experiment, chickpeas were painted with the sulfur compounds w-propyldithiolane and w-propylthiolane from stoat anal gland secretion and 2,4,5-trimethylthiazoline (Fig. 3.1, p. 37) from fox feces. The chickpeas were planted and wild mice and house mice were tested to see if they would dig up and eat the peas. Wild mice remembered the predator odors better after odor exposure for 1 or 4 weeks and, consequently, may be better than laboratory mice at risk assessment (Coulston etal, 1993). 

Coulston, S., Stoddart, D. M., and Crump, D. R. (1993). Use of predator odors to protect chick-peas from predation by laboratory and wild mice. Journal of Chemical Ecology 19, 607-612. 

Pandey, S. D., and Pandey, S. C. (1986). Estrus suppression in wild mice source of pheromonal cue. ActaFhysiologicaHmgarica 67,387-392. 

Reidl, L.S., Kinoshita, C.M., Steiner, L.A. (1992). Wild mice express an Ig VX gene that differs from any VX in BALB/c but resembles a human VX subgroup. J. Immunol. 149,471-480. 

Gar drrer MB, Herrderson BE, Officer JE, Rorrgey RW, Parker JC, Oliver C, Estes JD, Huebner RJ (1973) A sporrtarreous lower motor rreuT orr disease apparently caused by irrdigerrous type-C RNA virus hr wild mice. J Natl Cancer Irrst 51 1243—1254. 

Liu, X., Matsuda, T., and Shibutani, S. (2008) Oxidative DNA damage in XPC-knockout and its wild mice treated with equine estrogen. Chem. Res. 

Guenet, J-L. Bonhomme, F., 2003, Wild mice an ever-increasing contribution to a popular mammalian... 

Kuhn, B. F., Rochelle, M. J., and Kardong, K. V., 1991, Effects of rattlesnake (Crolalus viridis oreganus) envenomation upon the mobility and death rate of laboratory mice (Mus musculus) and wild mice (Peromyscus maniculatus). Bull. Md. Herp. Soc. 27(4) 189-194. 

The major urinary proteins (MUPs) are secreted abundantly into mouse urine as a normal condition. MUPs are thought to be involved in olfactory communication as their distinctive barrel shape allows them to bind two semiochemical molecules. Production of MUPs results from simultaneous expression of a number of closely related MUP genes the mature proteins therefore have heterogeneous amino acid sequences. Whilst this heterogeneity has been characterised in inbred mice, little is known about the heterogeneity of MUPs in wild mice. No function has ever been ascribed to MUP heterogeneity. 

In this study, the molecular mass and net charge of MUPs from six wild mice, taken from two separate populations, have been determined by electrospray ionization mass spectrometry and anion exchange chromatography respectively. This method of analysis uniquely identifies individual MUPs and has allowed an accurate determination of the number of different MUPs produced by these animals. In this limited sample, the number is much greater than previously observed in inbred mice. The results are discussed both in terms of the total number of MUPs characterised and the variation in heterogeneity between individual animals and populations. 

Figure 1. Molecular mass heterogeneity of MUPs from wild and inbred mice. The molecular mass of MUPs from six wild mice, taken from two separate populations (M and HH), and from two inbred strains (BALB/c and C57BL/6) was determined by ESI/MS. In each spectrum, MUPs with a particular mass are represented by a bold vertical line. The percentage abundance (y axis) is a measure of the amount of MUP at a given mass, relative to the most abundant peak in the spectrum.

The anion exchange profiles from six wild mice and two inbred strains are shown in Figure 2. The six wild animals exhibited 52 discernible anion exchange peaks. There was some variation in the complexity of the profiles obtained. The least complex profile, consisting of 6 discernible peaks, was M24 whereas the profiles from HHIO and HH13, each contained 10 peaks. The two populations were similar in their complexity 28 discernible peaks were observed in the HH population whilst 24 were observed in the M population. The inbred MUP profiles are on the whole less complex than their wild counterparts. Both C57BL/6 and BALB/c showed fewer resolved peaks than five of the six wild samples. The least complex sample of the whole study was C57BL/6 from which only 5 discernible peaks were produced. 

The level of heterogeneity in MUPs from wild mice was considerably greater than that observed in inbred animals. Although many of the MUPs characterised by each... 

Both laboratory and wild mice were used in the following studies. Males were used in these initial investigations because the propensity for aggression between them is thought to be the basis of formation and maintenance of territories in populations of house mice (Bronson, 1979). 

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