Journal of Molecular Evolution

, Volume 24, Issue 3, pp 272–279

Recruitment of lysozyme as a major enzyme in the mouse gut: Duplication, divergence, and regulatory evolution


  • Michael F. Hammer
    • Department of BiochemistryUniversity of California
  • James W. Schilling
    • California Biotechnology
  • Ellen M. Prager
    • Department of BiochemistryUniversity of California
  • Allan C. Wilson
    • Department of BiochemistryUniversity of California

DOI: 10.1007/BF02111240

Cite this article as:
Hammer, M.F., Schilling, J.W., Prager, E.M. et al. J Mol Evol (1987) 24: 272. doi:10.1007/BF02111240


Two major types of lysozymec (M and P) occur in the mouse genus,Mus, and have been purified from an inbred laboratory strain (C58/J) ofM. domesticus. They differ in physical, catalytic, and antigenic properties as well as by amino acid replacements at 6 of 49 positions in the amino-terminal sequence. Comparisons with four other mammalian lysozymesc of known sequence suggest that M and P are related by a gene duplication that took place before the divergence of the rat and mouse lineages. M lysozyme is present in most tissues; achieves its highest concentration in the kidney, lung, and spleen; and corresponds to the lysozyme partially sequenced before from another strain ofM. domesticus. InM. domesticus and several related species, P lysozyme was detected chiefly in the small intestine, where it is probably produced mainly by Paneth cells. A survey of M and P levels in 22 species of muroid rodents (fromMus and six other genera) of known phylogenetic relationships suggests that a mutation that derepressed the P enzyme arose about 4 million years ago in the ancestor of the housemouse group of species. Additional regulatory shifts affecting M and P levels have taken place along lineages leading to other muroid species. Our survey of 187 individuals of wild house mice and their closest allies reveals a correlation between latitude of origin and level of intestinal lysozyme.

Key words

Enzymatic propertiesPrimary sequence22 Rodent speciesTissue distributionLatitudinal variation

Copyright information

© Springer-Verlag New York Inc. 1987