Biochemical Genetics

, Volume 17, Issue 7, pp 599–619

Genetic variation, inheritance, and quaternary structure of malic enzyme in brook trout (Salvelinus fontinalis)


  • Mark Stoneking
    • Department of BiologyThe Pennsylvania State University
  • Bernie May
    • Department of BiologyThe Pennsylvania State University
  • James E. WrightJr.
    • Department of BiologyThe Pennsylvania State University

DOI: 10.1007/BF00502121

Cite this article as:
Stoneking, M., May, B. & Wright, J.E. Biochem Genet (1979) 17: 599. doi:10.1007/BF00502121


Electrophoretic variation is described for malic enzyme (ME) for the first time in brook trout (Salvelinus fontinalis). Since the quaternary structure of ME was not clear from examination of banding patterns in brook trout alone, ME phenotypes in rainbow trout (Salmo gairdneri) × brook trout hybrids as well as in esocid species demonstrated that ME is tetrameric. A model of two duplicated loci is proposed to account for the observed variation. One locus (ME-2) is fixed and one locus (ME-1) is variable with three electrophoretically distinct alleles; the protein products of ME-1 are reduced in activity relative to the protein products of ME-2. Joint segregation was examined between ME-1 and ten other biochemical loci in brook trout, and between ME-1, ME-2, and nine other biochemical loci in a splake—lake trout (Salvelinus namaycush) × brook trout hybrid—backcross. All pairwise examinations showed random assortment except ME-2 with an isocitrate dehydrogenase locus (IDH-3), which showed complete linkage in the splake backcross. This may be due to a chromosomal aberration.

Key words

malic enzymeinheritance and joint segregationbrook troutquaternary structureinterspecies hybrids

Copyright information

© Plenum Publishing Corporation 1979