Food-induced esterase electromorphs in Carinarion spp. and their effects on taxonomic data analysis (Gastropoda, Pulmonata, Arionidae).
Nonspecific esterases (EST) are often used to measure genetic variation, yet they may be influenced by environmental factors such as food, climate and age. This may produce misleading similarity indices and genetic diversity estimates (i.e., clone or strain diversities in uniparental organisms). Therefore, polyacrylamide gel electrophoresis (PAGE) and isoelectric focusing (IEF) were used to investigate environmental effects on the EST variation in natural Carinarion populations, as well as in 45 individuals that were raised individually on carrots to produce offspring by selfing. Food effects on EST profiles in these progenies were examined by raising them on different food items (lettuce, nettle, or paper). Our results indicated that: (i) Arion (Carinarion) fasciatus and A. (C.) silvaticus show species-specific EST profiles, (ii) A. fasciatus-like outcrossers most probably are conspecific with A. fasciatus s.s., (iii) not all EST variation has a Mendelian basis since lettuce and nettle altered EST profiles, and (iv) food effects on EST profiles differed strongly between individuals. Although food-induced EST profiles did not affect taxonomic interpretations, they did inflate genetic diversity estimates and thus provided misleading population-genetic data.
Jordaens
K
K
Department of Biology, University of Antwerp (RUCA), Belgium. jordaens@ruca.ua.ac.be
Van Riel
P
P
Verhagen
R
R
Backeljau
T
T
D000818:Animals; D043182:Carboxylesterase; D002265:Carboxylic Ester Hydrolases / Q000032:analysis* / Q000145:classification; D018552:Daucus carota; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods*; D005502:Food; D007525:Isoelectric Focusing / Q000379:methods*; D007527:Isoenzymes / Q000032:analysis / Q000145:classification; D008974:Mollusca / Q000201:enzymology*
D007527:Isoenzymes; D002265:Carboxylic Ester Hydrolases; D043182:Carboxylesterase