Microsatellite markers for the notothenioid fish Lepidonotothen nudifrons and two congeneric species.
BACKGROUND
Loss of genetic variability due to environmental changes, limitation of gene flow between pools of individuals or putative selective pressure at specific markers, were previously documented for Antarctic notothenioid fish species. However, so far no studies were performed for the Gaudy notothen Lepidonotothen nudifrons. Starting from a species-specific spleen transcriptome library, we aimed at isolating polymorphic microsatellites (Type I; i.e. derived from coding sequences) suitable to quantify the genetic variability in this species, and additionally to assess the population genetic structure and demography in nototheniids.


RESULTS
We selected 43,269 transcripts resulting from a MiSeq sequencer run, out of which we developed 19 primer pairs for sequences containing microsatellite repeats. Sixteen loci were successfully amplified in L. nudifrons. Eleven microsatellites were polymorphic and allele numbers per locus ranged from 2 to 17. In addition, we amplified loci identified from L. nudifrons in two other congeneric species (L. squamifrons and L. larseni). Thirteen loci were highly transferable to the two congeneric species. Differences in polymorphism among species were detected.


CONCLUSIONS
Starting from a transcriptome of a non-model organism, we were able to identify promising polymorphic nuclear markers that are easily transferable to other closely related species. These markers can be a key instrument to monitor the genetic structure of the three Lepidonotothen species if genotyped in larger population samples. When compared with anonymous loci isolated in other notothenioids, i.e. Type II (isolated from genomic libraries), they offer the possibility to test how the effects of occurring environmental change influence the population genetic structure in each species and subsequently the composition of the entire ecosystem.
Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, Bremerhaven, 27570, Germany. chiara.papetti@unipd.it.
Chiara
C
Papetti
Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, Bremerhaven, 27570, Germany.
Lars
L
Harms
Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, Bremerhaven, 27570, Germany.
Jutta
J
Jürgens
Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, Bremerhaven, 27570, Germany.|University of Bremen, BreMarE-Bremen Marine Ecology, Leobener Str. NW2, 28359, Bremen, Germany.
Tina
T
Sandersfeld
Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, Bremerhaven, 27570, Germany.
Nils
N
Koschnick
Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, Bremerhaven, 27570, Germany.|Institute for Cell Biology and Zoology, Heinrich-Heine-University, Universitätsstrasse 1, Düsseldorf, 40225, Germany.
Heidrun Sigrid
HS
Windisch
Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, Bremerhaven, 27570, Germany.
Rainer
R
Knust
Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, Bremerhaven, 27570, Germany.
Hans-Otto
HO
Pörtner
Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, Bremerhaven, 27570, Germany.
Magnus
M
Lucassen
D000818:Animals; D020869:Gene Expression Profiling / Q000379:methods*; D005787:Gene Frequency; D005838:Genotype; D018895:Microsatellite Repeats / Q000235:genetics*; D010473:Perciformes / Q000145:classification / Q000235:genetics*; D011110:Polymorphism, Genetic; D013045:Species Specificity; D013154:Spleen / Q000378:metabolism; D059467:Transcriptome / Q000235:genetics*
Antarctica; Gaudy notothen; Lepidonotothen larseni; Lepidonotothen squamifrons; Nototheniidae; Population differentiation; Southern ocean