TY - JOUR
T1 - Local adaptation at fine spatial scale through chromosomal inversions and mito-nuclear epistasis
T2 - findings in Drosophila subobscura (Diptera: Drosophilidae)
AU - Veselinovic, Marija Savic
AU - Kurbalija Novicic, Zorana
AU - KENIG5, BOJAN
AU - Jelic, Mihailo
AU - PATENKOVIĆ, ALEKSANDRA
AU - TANASKOVIĆ, MARIJA
AU - Pertoldi, Cino
AU - Stamenkovic-Radak, Marina
AU - Andjelkovic, Marko
PY - 2019
Y1 - 2019
N2 - To explore local adaptation in wild populations at a fine spatial scale we characterized the genetic variability of eight closely located populations of Drosophila subobscura and its associations with microhabitat environmental conditions. Three different genetic markers were assessed: chromosomal inversions, a SNP of mitochondrial ND5 gene and nuclear microsatellites. Population genetic analyses of chromosomal variability revealed significant genetic differentiation between these populations. Gene arrangement frequencies on the E chromosome contributed most to these differences. We also investigated role of mito-nuclear epistasis in mitochondrial genome differentiation and revealed weak linkage disequilibrium (LD) exclusively between O3+4 inversion arrangement and mitochondrial DNA haplotype I in two populations. In addition, the trend in the LD between OST chromosomal arrangement and haplotype II was general in the total sample. Microsatellite analysis revealed an absence of stochastic processes, like census reduction, upon population differentiation. Only a small amount of the genetic variation is related to geographic distance, while most (97%) is attributable to other factors and in some degree to microhabitat variables (temperature, humidity). The analysis of these factors revealed they effect inversion arrangement frequencies, especially E1+2+9, EST and OST. Even though this model organism is known for its high mobility and mostly large effective population size, the results presented here reveal that local adaptations can occur even at a small spatial scale. We propose that locally adapted alleles within chromosomal inversions, as well as joint selective pressures acting on mitochondrial and nuclear genomes, are responsible for the observed adaptation to microhabitat conditions.
AB - To explore local adaptation in wild populations at a fine spatial scale we characterized the genetic variability of eight closely located populations of Drosophila subobscura and its associations with microhabitat environmental conditions. Three different genetic markers were assessed: chromosomal inversions, a SNP of mitochondrial ND5 gene and nuclear microsatellites. Population genetic analyses of chromosomal variability revealed significant genetic differentiation between these populations. Gene arrangement frequencies on the E chromosome contributed most to these differences. We also investigated role of mito-nuclear epistasis in mitochondrial genome differentiation and revealed weak linkage disequilibrium (LD) exclusively between O3+4 inversion arrangement and mitochondrial DNA haplotype I in two populations. In addition, the trend in the LD between OST chromosomal arrangement and haplotype II was general in the total sample. Microsatellite analysis revealed an absence of stochastic processes, like census reduction, upon population differentiation. Only a small amount of the genetic variation is related to geographic distance, while most (97%) is attributable to other factors and in some degree to microhabitat variables (temperature, humidity). The analysis of these factors revealed they effect inversion arrangement frequencies, especially E1+2+9, EST and OST. Even though this model organism is known for its high mobility and mostly large effective population size, the results presented here reveal that local adaptations can occur even at a small spatial scale. We propose that locally adapted alleles within chromosomal inversions, as well as joint selective pressures acting on mitochondrial and nuclear genomes, are responsible for the observed adaptation to microhabitat conditions.
KW - Diptera
KW - Drosophilidae
KW - Drosophila subobscura
KW - genetic differentiation
KW - high dispersion
KW - chromosomal inversion
KW - ND5
KW - microsatellites
KW - local adaptation
U2 - 10.14411/eje.2019.051
DO - 10.14411/eje.2019.051
M3 - Journal article
SN - 1210-5759
VL - 116
SP - 492
EP - 503
JO - European Journal of Entomology
JF - European Journal of Entomology
ER -