acid-phosphatase and Chromosome-Inversion

Seasonal variation (spring, early summer, late summer, and autumn) of gametic disequilibrium between gene arrangements (OST and O3+4) of the O chromosome and Lap, Pept-1, and Acph allozyme loci, located inside these inversions, has been recorded in a natural population of Drosophila subobscura during seven years over a 15-year period. The length of the study allowed us to investigate the temporal variation of the allozyme-inversion associations by statistical methods of time series analysis. Cyclic seasonal changes of allozyme-inversion associations for both Lap and Pept-1 are detected in the natural population. In both cases, the patterns of seasonal change are due to the seasonal change of frequency of Lap and Pept-1 allozymes occurring exclusively within the OST gene arrangement. In contrast, the allozyme frequencies at these loci within the O3+4 gene arrangement are stable along seasons. The patterns of temporal variation of allozyme-inversion associations for Lap and Pept-1 in the natural population are contrasted with those previously published that correspond to gene arrangements of the O chromosome and nucleotide polymorphism at the rp49 region located inside these inversions, suggesting that natural selection is operating on these allozyme-inversion associations.

Topics: Acid Phosphatase; Animals; Biological Evolution; Chromosome Inversion; Chromosome Mapping; Drosophila; Endopeptidases; Gene Rearrangement; Isoenzymes; Leucyl Aminopeptidase; Linkage Disequilibrium; Seasons

Allozymes of the Ap-3 locus in Drosophila pseudoobscura show very strong associations with chromosome 3 inversions. The 0.98 electrophoretic allele is associated with The TL, SC, CH and PP gene arrangements, while the 1.00 electrophoretic allele is characteristic of the AR and ST gene arrangements. Variation in relative 0.98 and 1.00 AP-3 allozyme activities of chromosome 3 isogenic strains was examined on acrylamide gels in F1 heterozygotes obtained by crossing these strains individually to a reference strain with a slower 0.87 mobility allozyme. F2 analyses demonstrated that the activity variants co-segregate with the Ap-3 locus. Both 0.98 and 1.00 allelic classes are polymorphic for AP-3 activities. In contrast to the virtual monomorphism for an electrophoretic allele, each inversion is polymorphic for AP-3 activities. These results reveal substantially more genetic differentiation among gene arrangements than is evident from electrophoretic allele comparisons. Strains having the PP arrangement are distinct from TL strains in their AP-3 activity expression, and ST strains have a wider range of variation than AR strains. In contrast, no geographical differentiation is evident for strains from the Bogota population of D. pseudoobscura.

Topics: Acid Phosphatase; Animals; Chromosome Inversion; Drosophila; Electrophoresis, Polyacrylamide Gel; Genetic Variation; Isoenzymes; Phenotype

Associations of alleles of the acid phosphatase-3 locus with the different third-chromosome inversions from different populations of D. pseudoobscura are described. We observe only the allele AP-3(1.0) in the Standard and Arrowhead inversions and the allele AP-3.98 in the Santa Cruz, Treeline, Cuernavaca and the Pikes Peak arrangements. The Chiricahua gene arrangement is polymorphic.

Topics: Acid Phosphatase; Alleles; Animals; Chromosome Aberrations; Chromosome Inversion; Drosophila; Female; Gene Frequency; Genes; Male; Mexico; Polymorphism, Genetic; United States

The Standard and Sex Ratio gene arrangements of the X chromosome of D. pseudobscura differ from each other in allele frequencies at the four X chromosome loci, esterase-5, adult acid phosphatase-6, phosphoglucomutase-1 and octanol dehydrogenase-3. The Standard arrangement which is the common arrangement in all populations is polymorphic at these loci in varying degrees, the geographically less widespread Sex Ratio arrangement has little polymorphism and is genically predominantly E-5(1.04) AP-6(-) Pgm1(1.0) ODH-3(1.0). The Sex Ratio arrangement from different populations is alike at all of the four loci, the Standard arrangement shows some gene frequency differences among populations. The Standard and Sex Ratio arrangements differ from each other by three inversions which suggests that the two arrangements are "old". Gene differences between these two chromosome arrangements can be explained due to differential natural selection of alleles in the Standard and Sex Ratio arrangments.-The order and percent recombination among these four loci in the Standard arrangement are: E-5-.294-AP-6-.335-Pgm-1-.024-ODH-3. The Standard X chromosomes from four different wild populations were analyzed for evidence of linkage disequilibrium between pairs of loci at these four loci. No evidence of linkage disequilibrium between pairs of loci was obtained. However, when linkages involving simultaneously three loci, E-5, AP-6 and Pgm-1 are considered, then significant departure from linkage equilibrium is observed.

Topics: Acid Phosphatase; Alcohol Oxidoreductases; Alleles; Animals; Chromosome Inversion; Chromosome Mapping; Drosophila; Esterases; Female; Gene Frequency; Genetic Linkage; Male; Phosphoglucomutase; Polymorphism, Genetic; Recombination, Genetic; Selection, Genetic; Sex Chromosomes; Sex Ratio