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Simple Summary: The phylum Onychophora has only about 200 described species around the world. Commonly known as velvet worms or peripatuses, they are soft-bodied, many-legged invertebrates. Onychophora hunt at night and live in moist places on land. On the outside, they all look very similar which makes species identification difficult. In Aotearoa, New Zealand, the species within the endemic genus of live-bearing Peripatoides are known as ngāokeoke. One species in this genus is distinguished by having 16 pairs of legs (P. suteri), while others have 15 pairs of legs. One species (P. indigo) has a distinctive blue colour, but other taxa have a mix of orange and blue pigmentation. Five northern species within Peripatoides were established from genetic evidence of reproductively isolated sympatric populations. Morphological variation in this genus is re-examined using additional sampling from North Island and South Island, New Zealand. A re-analysis of nuclear markers and new DNA sequences confirms that five species are cryptic and their known ranges have been updated. Three new ngāokeoke species in the genus Peripatoides are described from South Island. These three new species represent distinct genetic lineages with distinct pigmentation patterns. (1) Background: Originally described as a single taxon, Peripatoides novaezealandiae (Hutton, 1876) are distributed across both main islands of New Zealand; the existence of multiple distinct lineages of live-bearing Onychophora across this spatial range has gradually emerged. Morphological conservatism obscured the true endemic diversity, and the inclusion of molecular tools has been instrumental in revealing these cryptic taxa. (2) Methods: Here, we review the diversity of the ovoviviparous Onychophora of New Zealand through a re-analysis of allozyme genotype data, mitochondrial DNA cytochrome oxidase subunit I sequences, geographic information and morphology. (3) Results: New analysis of the multilocus biallelic nuclear data using methods that do not require a priori assumptions of population assignment support at least six lineages of ovoviviparous Peripatoides in northern New Zealand, and mtDNA sequence variation is consistent with these divisions. Expansion of mitochondrial DNA sequence data, including representation of all existing taxa and additional populations extends our knowledge of the scale of sympatry among taxa and shows that three other lineages from southern South Island can be added to the Peripatoides list, and names are proposed here. In total, 10 species of Peripatoides can be recognised with current data. [ABSTRACT FROM AUTHOR]

(1) Background: Originally described as a single taxon, Peripatoides novaezealandiae (Hutton, 1876) are distributed across both main islands of New Zealand; the existence of multiple distinct lineages of live-bearing Onychophora across this spatial range has gradually emerged. Morphological conservatism obscured the true endemic diversity, and the inclusion of molecular tools has been instrumental in revealing these cryptic taxa. (2) Methods: Here, we review the diversity of the ovoviviparous Onychophora of New Zealand through a re-analysis of allozyme genotype data, mitochondrial DNA cytochrome oxidase subunit I sequences, geographic information and morphology. (3) Results: New analysis of the multilocus biallelic nuclear data using methods that do not require a priori assumptions of population assignment support at least six lineages of ovoviviparous Peripatoides in northern New Zealand, and mtDNA sequence variation is consistent with these divisions. Expansion of mitochondrial DNA sequence data, including representation of all existing taxa and additional populations extends our knowledge of the scale of sympatry among taxa and shows that three other lineages from southern South Island can be added to the Peripatoides list, and names are proposed here. In total, 10 species of Peripatoides can be recognised with current data.

Attempts to determine interspecific differences in patterns of protein variation in edible frog species have been relatively few. Therefore, this study determined the genetic variation in populations of Hoplobatrachus occipitalis and Xenopus muelleri in two locations [University of Ibadan (UI) and Igbo Oloyin area (IO)] in Ibadan, Nigeria, using five allozyme loci. Eighty (80) edible frogs comprising twenty (20) live samples each of H. occipitalis and X. muelleri species from IO and UI were collected. 1ml of blood was drawn per sample via cardiac venipuncture. Plasma fractions were obtained and subjected to Cellulose Acetate Electrophoresis to determine the genetic variations at Haemoglobin (HB), Carbonic anhydrase (CA), Transferrin (TF), Albumin (AL) and Esterase (EST) loci. Test for Hardy–Weinberg Equilibrium (HWE; ), Heterozygosity [observed (Ho) and expected (He)] and Genetic differentiation (FST) were estimated. Significant deviations from HWE were observed at several loci in all the populations. Ho was higher (than He) for both populations of H. occipitalis but lower for both populations of X. muelleri. FST was 0.0559 and 0.0264 for the populations of H. occipitalis and X. muelleri, respectively. There is an indication of evolutionary forces in operation in the IO populations of H. occipitalis and X. muelleri.

A non‐synonymous single nucleotide polymorphism (SNP) underlies a diallelic allozyme polymorphism at the mitochondrial NADP‐dependent mMEP‐2* locus in Atlantic salmon (Salmo salar L.). The resultant amino acid substitution, which alters the charge of the allelic products, matches the differential mobility of the two allozyme alleles, whereas allozyme and SNP assays revealed genotyping concordance in 257 of 258 individuals. A single mismatch, homozygous allozyme vs. heterozygote SNP, suggests the presence of a second, less common null allele. [ABSTRACT FROM AUTHOR]

Background : Understanding population genetic structures is crucial for planning and implementing conservation programmes to preserve species' adaptive and evolutionary potential and thus ensure their long-term persistence. The grey mullet ( Mugil cephalus ) is a globally distributed coastal fish. Its populations in waters surrounding Taiwan on the western Pacific fringe are divided into at least two stocks (migratory and residential), but questions remain regarding their genetic divergence and gene flow. Methods and Results : To cast more light on this, allozyme variations at 21 presumptive gene loci of 1217 adult grey mullets from 15 localities in Japan, Taiwan and mainland China, and four gene loci from 1470 juveniles from three localities in Taiwan were used to investigate patterns of genetic variation. The mean expected heterozygosity (He) was 0.128-ranging from 0.031 (Matsu) to 0.442 (Kaoping)-and the mean observed heterozygosity (Ho) was 0.086-ranging from 0.017 (Kaohsiung) to 0.215 (Kaoping). Both AMOVA and the high overall mean FST of 0.252 indicated enormous genetic differentiation among populations and the positive mean value of FIS was 0.328, indicating a deficiency of heterozygotes. PCoA indicated that the samples of M. cephalus could be split into three groups and STRUCTURE analysis showed that all individuals were grouped into three genetic clusters. The results of mutation-drift equilibrium tests did not suggest that the populations experienced any recent genetic bottleneck. The results from all localities in the present investigation showed significant change in the GPI-A genotype frequencies with latitudes-e.g., increases in GPI-A*135/135 homozygote frequencies and GPI-A*100/100 frequencies were highly correlated with latitudinal cline. All migratory populations with the GPI-A genotype were almost exclusively the GPI-A*100/100 homozygote. During the life history of M. cephalus , the GPI-A*100/135 heterozygote frequency significantly decreases with age. Conclusions : Based on these data, we suggest that each GPI-A genotype represents trait combinations of higher fitness in some portions of the environment. Furthermore, the genotypic frequencies change in accordance with life stages, suggesting that selection occurs throughout the life span.

Attempts to determine interspecific differences in patterns of protein variation in edible frog species have been relatively few. Therefore, this study determined the genetic variation in populations of Hoplobatrachus occipitalis and Xenopus muelleri in two locations [University of Ibadan (UI) and Igbo Oloyin area (IO)] in Ibadan, Nigeria, using five allozyme loci. Eighty (80) edible frogs comprising twenty (20) live samples each of H. occipitalis and X. muelleri species from IO and UI were collected. 1ml of blood was drawn per sample via cardiac venipuncture. Plasma fractions were obtained and subjected to Cellulose Acetate Electrophoresis to determine the genetic variations at Haemoglobin (HB), Carbonic anhydrase (CA), Transferrin (TF), Albumin (AL) and Esterase (EST) loci. Test for Hardy-Weinberg Equilibrium (HWE; α0.05), Heterozygosity [observed (Ho) and expected (He)] and Genetic differentiation (FST) were estimated. Significant deviations from HWE were observed at several loci in all the populations. Ho was higher (than He) for both populations of H. occipitalis but lower for both populations of X. muelleri. FST was 0.0559 and 0.0264 for the populations of H. occipitalis and X. muelleri, respectively. There is an indication of evolutionary forces in operation in the IO populations of H. occipitalis and X. muelleri. [ABSTRACT FROM AUTHOR]

In order to reveal the genetic relationship of tetraploids and pentaploids in the agamospermous species Taraxacum albidum Dahlst., an allozyme study was carried out. Approximately 200 plants putatively identified as T. albidum were collected mainly from the Kyushu Island of Japan, and analyzed by enzyme electrophoresis. Two multilocus genotypes at 14 presumptive loci of nine enzymes, Type A and Type B, were detected. Most of the sample plants showed uniclonal Type A, which corresponds to "T. albidum" as reported in our previous paper. Type B, which is also uniclonal, was found at fewer localities and was clearly different from Type A in the allele composition of pgi‐2 and pgm‐1, as well as in the allele dosage at mdh and sod‐1. By means of flow cytometry and chromosome count, the ploidy levels of Type A and Type B were shown to be pentaploid and tetraploid, respectively. A comparison of the allele composition suggests a hybrid origin of pentaploid T. albidum (Type A) from an unreduced gamete of Type B and a reduced gamete of any diploid Taraxacum species. [ABSTRACT FROM AUTHOR]

The clonal structure of populations of the weevil Eusomus ovulum (Coleoptera, Curculionidae) from several regions of Ukraine was analyzed. The significant interpopulation differentiation between populations from different region was demonstrated. The hypothesis of multiple origins of the hybrid form Eusomus ovulum from several parental species was proposed.

Th e clonal structure of populations of the weevil Eusomus ovulum Germar, 1824 (Coleoptera, Curculionidae) from several regions of Ukraine was analyzed. Th e signifi cant diff erentiation between populations from different region was demonstrated. Th e hypothesis of multiple origins of the hybrid form E. ovulum from several parental species is proposed [ABSTRACT FROM AUTHOR]

Genotyping is an essential procedure for identifying agronomically useful genes and analyzing population structure. Various types of genetic marker systems have been developed in common buckwheat (Fagopyrum esculentum Moench). In the 1980s, morphological and allozyme markers were used to construct linkage maps. Until the early 2000s, allozyme markers were widely used in population genetics studies. Such studies demonstrated that cultivated common buckwheat likely originated in the Sanjiang area of China. In the late 1990s and early 2000s, advances in PCR technology led to the development of various DNA marker systems for use in linkage mapping. However, PCR-based markers did not completely cover the genome, making genetic analysis of buckwheat challenging. The subsequent development of next generation sequencing, a game-changing technology, has allowed genome-wide analysis to be performed for many species. Indeed, 8,884 markers spanning 756 loci were recently mapped onto eight linkage groups of common buckwheat; these markers were successfully used for genomic selection to increase yield. Furthermore, draft genome sequences are now available in the Buckwheat Genome DataBase (BGDB). In this review, I summarize advances in the breeding and genetic analysis of common buckwheat based on contemporary genetic marker systems. [ABSTRACT FROM AUTHOR]

Characterizing population structure using neutral markers is an important first step in association genetic studies in order to avoid false associations between phenotypes and genotypes that may arise from non-selective demographic factors. Population structure was studied in a wide sample of ∼1,300 coastal Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco var. menziesii] trees from Washington and Oregon. This sample is being used for association mapping between cold hardiness and phenology phenotypes and single-nucleotide polymorphisms in adaptive-trait candidate genes. All trees were genotyped for 25 allozyme and six simple sequence repeat (SSR) markers using individual megagametophytes. Population structure analysis was done separately for allozyme and SSR markers, as well as for both datasets combined. The parameter of genetic differentiation (θ or F ST) was standardized to take into account high within-population variation in the SSR loci and to allow comparison with allozyme loci. Genetic distance between populations was positively and significantly correlated with geographic distance, and weak but significant clinal variation was found for a few alleles. Although the STRUCTURE simulation analysis inferred the same number of populations as used in this study and as based on previous analysis of quantitative adaptive trait variation, clustering among populations was not significant. In general, results indicated weak differentiation among populations for both allozyme and SSR loci (θ s = 0.006–0.059). The lack of pronounced population subdivision in the studied area should facilitate association mapping in this experimental population, but we recommend taking the STRUCTURE analysis and population assignments for individual trees (Q-matrix) into account in association mapping.

Mammals have played a foundational role in the explosive growth of phylogeography over the past 30 years that it has been a recognized discipline. Novel discoveries of geographic patterns and processes using phylogeographic approaches have integrated disciplines including biogeography, evolutionary biology, ecology, and conservation biology. Here, we use several approaches to survey the scope and influence of phylogeography, beginning with use of a well-studied family of North American rodents to contrast information content derived from DNA-based phylogeography versus a popular older method, allozyme electrophoresis, of assaying genetic variation within and among species across geography. We conclude that phylogeography has elevated the quality of insights attainable regarding, for example, the causal role of Earth history events in processes including lineage divergence, speciation, and adaptive evolution. Next, we use searches of the Web of Science with an array of terms that return information on molecular markers employed, numbers of individuals and localities examined, time frames investigated, historical processes and ways that species and biotas have responded to Earth history, design of phylogeographic studies (e.g. single-taxon versus comparative), and current gaps in taxonomic and geographic sampling. Highlighted results from phylogeographic assays include: an average of 3.3 cryptic lineages per taxonomic species in rodents; a bias in number of studies toward less-diverse biogeographic regions; and a relatively low number of mammalian genera studied. We conclude with predicted and recommended directions for future growth in mammalian phylogeography, including prospects for an increasing role of next generation-based genomics. [ABSTRACT FROM AUTHOR]

In natural systems plant-insect interactions are influenced by several factors. For instance plants could be characterised by the presence of defensive chemicals and herbivores are forced to evolve resistance against them. There are several studies on induced plant defence, which indicate it can mediate competition between herbivorous insects, shaping host plant choice and community structure. Therefore, realized host plant use can be much narrower than the potential one. A laboratory experiment was done to clear up the possible difference in host plant utilization ability of Melitaea phoebe and Melitaea ornata, especially their utilization of Cirsium pannonicum. The caterpillars were reared individually on three different species of host plant (Ci. pannonicum, Ci. arvense and Centaurea scabiosa). The weights of the larvae were measured every second day and the data analysed using ANOVA. M. phoebe caterpillars developed well and all pupated when fed on Cirsium arvense and Centaurea scabiosa, whereas those fed on Cirsium pannonicum developed poorly and 10% died. In contrast, M. ornata developed well on Ci. pannonicum and the other two host plants. Despite this M. ornata was only found on Ci. pannonicum in Hungary.

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The clonal structure of the populations of nine weevil species (family Curculionidae) from central Ukraine was analyzed. Clonal diversity varied extensively among studied species. The level of clonal variation of some species (Otiorhynchus ligustici, O. raucus, Liophloeus tessulatus) is high, within some other species (O. tristis, Tropiphorus micans) it is low. The constant heterozygosity of lot of genes has been demonstrated that it may be a proof of the hybrid origin of the studied weevil populations. The asymmetry of some obtained electrophoretic spectra was observed. Th is can be a consequence of their polyploid nature. The significant interpopulation diff erentiation of most of the species studied was demonstrated. [ABSTRACT FROM AUTHOR]

Eutrema edwardsii R.Br. ( Brassicaceae) is an arctic-alpine mustard with a circumpolar distribution. Its closest relative, Eutrema penlandii Rollins, is a federally listed, threatened species that is endemic to the Mosquito Range in the Southern Rocky Mountains of Colorado, USA. As part of a larger project addressing the systematics of this species complex in North America, we conducted chromosome counts, flow cytometry, and allozyme analysis to test the hypothesis that these taxa comprise an autopolyploid complex. Within that context, it should be noted that a chromosome count has not been reported previously for E. penlandii. Results obtained from mitotic counts obtained for two populations of E. penlandii reveal this taxon to be diploid. Diploidy was confirmed using flow cytometry for an additional 15 individuals representing four populations. Previously published chromosome counts for E. edwardsii reveal a polyploid complex of tetraploid, hexaploid, and octaploid populations for which an autopolyploid origin has been presumed. However, allozyme analysis revealed an allopolyploid origin for E. edwardsii, as evidenced from fixed heterozygosity at six loci. Although our data suggest that E. penlandii is a close relative of one of the progenitors of E. edwardsii, the taxonomic identity of the other progenitor(s) cannot be elucidated from these data. The data reported herein support the recognition of E. penlandii as taxonomically distinct, which has implications for conservation, and reveal cryptic variation within E. edwardsii. [ABSTRACT FROM AUTHOR]

• DNA variation is characterized for aspartate aminotransferase allozymes in snails. • Allozyme alleles differ by 2–4 substitutions. • Aspartate aminotransferase is expressed in the snail at the constant level. • Aspartate aminotransferase gene is present in the snail genome in multiple copies. Allozymes present several classical examples of divergent selection, including the variation in the cytosolic aspartate aminotransferase (AAT) in the intertidal snails Littorina saxatilis. AAT is a part of the asparate-malate shuttle, in the interidal molluscs involved in the anaerobic respiration during desiccation. Previous allozyme studies reported the sharp gradient in the frequencies of the AAT100and the AAT120 alleles between the low and high shores in the Northern Europe and the differences in their enzymatic activity, supporting the role of AAT in adaptation to desiccation. However, the populations in the Iberian Peninsula showed the opposite allele cline. Using the mRNA sequencing and the genome pool-seq analyses we characterize DNA sequences of the different AAT alleles, report the amino acid replacements behind the allozyme variation and show that same allozyme alleles in Northern and Southern populations have different protein sequences. Gene phylogeny reveals that the AAT100 and the northern AAT120 alleles represent the old polymorphism, shared among the closely related species of Littorina, while the southern AAT120 allele is more recently derived from AAT100. Further, we show that the Aat gene is expressed at constitutive level in different genotypes and conditions, supporting the role of structural variation in regulation of enzyme activity. Finally, we report the location and the structure of the gene in the L. saxatilis genome and the presence of two additional non-functional gene copies. Altogether, we provide a missing link between the classical allozyme studies and the genome scans and bring together the results produced over decades of the genetic research. [ABSTRACT FROM AUTHOR]

Dyera lowii is an endemic and vulnerable tree species of commercial value as chewing gum found in peat swamp forests, scatteredly distributed in Sumatra, Kalimantan, and Peninsular Malaysia. Their existence is now under severe threat due to habitat conversion. This study is aimed to assess genetic diversity within four natural populations (Hampangen, Parahangan, Sebangau, Selat Nusa ) and one plantation in Central Kalimantan based on allozyme variation. Electrophoresis procedures were conducted with an isoelectric focusing polyacrylamide slab gel system. The result showed high genetic diversity (HE=0.52) and gene fl ow (3.402) seemed to be effective. A total of 14 alleles were found among all the analysed population. Mean number of alleles per locus (Aa) was 3.206, and the effective number of alleles per locus (Ae) was 2.21. Genetic differentiation between populations (FST) was signifi cant at the moderately level (0.0685). Most allozyme variation was found within population (93.2%). Special attention is essential to conserve a private allele of Got-1-e (9%) at Selat Nusa population. Sebangau population missed the alleles of Est-2-b and Got-1-a, as found in other populations. Selat Nusa population is expected to enhance the effective management for genetic resources conservation of this vulnerable species in the future.

Intraspecific genetic variation can have similar effects as species diversity on ecosystem function; understanding such variation is important, particularly for ecological key species. The brown trout plays central roles in many northern freshwater ecosystems, and several cases of sympatric brown trout populations have been detected in freshwater lakes based on apparent morphological differences. In some rare cases, sympatric, genetically distinct populations lacking visible phenotypic differences have been detected based on genetic data alone. Detecting such 'cryptic' sympatric populations without prior grouping of individuals based on phenotypic characteristics is more difficult statistically, though. The aim of the present study is to delineate the spatial connectivity of two cryptic, sympatric genetic clusters of brown trout discovered in two interconnected, tiny subarctic Swedish lakes. The structures were detected using allozyme markers, and have been monitored over time. Here, we confirm their existence for almost three decades and report that these cryptic, sympatric populations exhibit very different connectivity patterns to brown trout of nearby lakes. One of the clusters is relatively isolated while the other one shows high genetic similarity to downstream populations. There are indications of different spawning sites as reflected in genetic structuring among parr from different creeks. We used >3000 SNPs on a subsample and find that the SNPs largely confirm the allozyme pattern but give considerably lower F values, and potentially indicate further structuring within populations. This type of complex genetic substructuring over microgeographical scales might be more common than anticipated and needs to be considered in conservation management. [ABSTRACT FROM AUTHOR]

Dyckia brevifolia is an endemic rheophyte bromeliad that occurs exclusively in patches on rocky banks of the Itajaí-Açu River in southern Brazil. The genetic diversity of all known populations was carried out using allozyme markers and the total numbers of rosettes, reproductive rosettes, and clumps per population were characterized. The mating system was also investigated. Most rosettes were aggregated in groups, and the populations differed significantly in number of rosettes and reproductive rosettes per population. The outcrossing rate obtained was 8.2%, with predominant selfing. The populations presented an average of 1.4 alleles per locus and 27% of polymorphisms. The mean expected genetic diversity was 0.067. Downstream populations showed the highest genetic diversity which could be attributed to hydrochory (unidirectional river flow). Most genetic diversity is distributed among populations (FˆST = 0.402). Natural habitats of D. brevifolia are not recommended for the construction of hydroelectric plants given that it would seriously complicate in situ conservation of this species. Based on the results of this study, it can be concluded that between 35 and 161 reproductive rosettes must be collected for effective ex situ conservation, depending on the targeted population, or seeds collected from 157 seed-rosettes per population. [ABSTRACT FROM AUTHOR]

The lesser Egyptian jerboa Jaculus jaculus, is a member of the subfamily Dipodinae, known to have a number of subspecies. Previous studies of J. jaculus from North Africa found various morphological forms of unknown taxonomic status, which are frequently grouped into two taxa: J. jaculus and J. deserti. We assessed the taxonomic status of this taxon in Tunisia using allozymic (phylogenetic analysis of 23 genetic loci encoding 16 enzymatic proteins) and morphological (multivariate analysis of 13 craniodental characters) analyses of 136 J. jaculus specimens collected from seven localities within its distribution range. Allozymic analysis clearly indicated the existence of two distinct groups of J. jaculus, with a mean genetic distance (D) value of 0.99 and FST=0.52. Individuals within the two groups did not show any obvious geographical structuration, even within the Matmata locality which represents the meeting point for the two groups where they were found in sympatry. Additionally, morphometric analysis of 13 craniodental characters was clearly separated the two groups. These results were obtained over a very restricted area of the total distribution of J. jaculus and strongly suggest the occurrence of two separate and often sympatric species within the currently accepted J. jaculus in Tunisia: J. jaculus and J. deserti [Current Zoology 56 (4): 421–431, 2010].

Morphological and genetic variations within Salvia japonica (Lamiaceae) and its related species in Japan were analyzed for clarifying their taxonomic significance. The genetic variations were explored through chloroplast and nuclear ribosomal DNA sequences and allozyme polymorphisms. Since chromosome numbers characterized the genus of Salvia, we also examined whether the karyotypes were different. We examined 58 populations of S. japonica and 14 populations of others species of Salvia. Among the populations of S. japonica represented four forms (f. japonica, f. longipes, f. lanuginosa and f. albiflora). The size of chromosomes were various among Salvia spp. Based on the allozyme as well as the DNA sequence, the populations of S. japonica separated from the others Salvia species. The populations of S. japonica exhibited four combinations of the morphological characters. However, these combinations did not correlate to the four forms of S. japonica. In addition, the morphological variations did not correlate to the allozyme and DNA sequences. It is suggested that the four morphological variations as well as the four form of S. japonica should not considered to be a taxonomic unit; accordingly, S. japonica were considered to be still at the early stage of speciation process.

In order to test the potential ecological role of the Siculo-Tunisian Strait as a geographic barrier, the morphological and genetic variation of eight Tunisian samples of the sharpsnout seabream,Diplodus puntazzo, were studied, based on 23 truss network elements and 13 polymorphic allozyme loci. Significant morphological differences were observed between studied samples, especially between lagoon ones. Although genetic data did not support the detected morphometric variation,F-statistics indices (FISandFST) revealed a significant departure from panmixia with heterozygote deficiencies and slight genetic differentiation between samples. Genetic results suggested the existence of moderate and local genetic heterogeneity that can be explained by the chaotic genetic patchiness hypothesis. Morphological and genetic results showed that the Siculo-Tunisian Strait does not seem to act as a barrier limiting the connectivity between the natural populations ofD. puntazzo, at least at the scale of the Tunisian coast. Thus, the phenotypic variation identified in this study appears to be environmentally induced through the exploitation of different ecological niches and hydrodynamic constraints. [ABSTRACT FROM PUBLISHER]

A considerable amount of allozyme variation exists among different populations of a Drosophila species. Such allozyme variation can also be observed between two closely related species of Drosophila which show reproductive isolation but experience mating under laboratory conditions and produce hybrids. D. bipectinata and D. malerkotliana are two closely related sympatric species and belong to bipectinata species complex. Allozyme polymorphism studies conducted with them and their hybrids reveal that these two species have enough genetic differentiation due to allozyme variation at three enzyme coding loci; however, their hybrids exhibit common allozyme variants of both the species. The hybrids exhibit very little genetic differentiation from either of their parents. [ABSTRACT FROM AUTHOR]

Although theory suggests that hybrid zones can move or change structure over time, studies supported by direct empirical evidence for these changes are relatively limited. We present a spatiotemporal genetic study of a hybrid zone between Pseudacris nigrita and P. fouquettei across the Pearl River between Louisiana and Mississippi. This hybrid zone was initially characterized in 1980 as a narrow and steep 'tension zone,' in which hybrid populations were inferior to parentals and were maintained through a balance between selection and dispersal. We reanalyzed historical tissue samples and compared them to samples of recently collected individuals using microsatellites. Clinal analyses indicate that the cline has not shifted in roughly 30 years but has widened significantly. Anthropogenic and natural changes may have affected selective pressure or dispersal, and our results suggest that the zone may no longer best be described as a tension zone. To the best of our knowledge, this study provides the first evidence of significant widening of a hybrid cline but stasis of its center. Continued empirical study of dynamic hybrid zones will provide insight into the forces shaping their structure and the evolutionary potential they possess for the elimination or generation of species. [ABSTRACT FROM AUTHOR]

ABSTRACT Glutathione (GSH) structure-guided tripeptide analogues were designed and synthesized by solid phase technology, purified (≥95%) by RP and/or GF column chromatography, to identify those that, compared with GSH, exhibited similar or higher binding and catalytic efficiency toward the MDR-involved human GSTP1-1 isoenzyme, and could discriminate between the allozymic expression products of the polymorphic human GSTP1 gene locus, designated as hGSTP1*A (Ile104/Ala113), hGSTP1*B (Val104/Ala113), and hGSTP1*C (Val104/Val113). The analogues bear single amino acid alterations as well as alterations in more than one position. Some analogues showed remarkable allozyme selectivity, binding catalytically to A ( I, II, IV, XII), to C ( V and XVI), to A and C ( III, VII, XIV) or to all three allozymes ( XV). A heterocyclic substituent at positions 1 or 2 of GSH favors inhibition of A, whereas a small hydrophobic/hydrophilic amide substituent at position 2 (Cys) favors inhibition of B and C. Heterocyclic substituents at position 1, only, produce catalytic analogues for A, whereas less bulky and more flexible hydrophobic/hydrophilic substituents, at positions 1 or 3, lead to effective substrates with C. When such substituents were introduced simultaneously at positions 1 and 3, the analogues produced have no catalytic potential but showed appreciable inhibitory effects, instead, with all allozymes. It is anticipated that when GSH analogues with selective inhibitory or catalytic binding, were conjugated to allozyme-selective inhibitors of hGSTP1-1, the derived leads would be useful for the designing of novel chimeric inhibitors against the MDR-involved hGSTP1-1 allozymes. © 2016 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 330-344, 2016. [ABSTRACT FROM AUTHOR]

Patterns of clonal growth in natural populations of two Sagittaria species ( Sagittaria trifolia and Sagittaria pygmaea ) were studied based on allozyme data, and spatial autocorrelation analysis was employed to assess their clonal structures. Ramets per multilocus genotypes in the studied populations varied from 1.556 to 5.468, and showed distinct features in clonal intensity between the two species. High clonal diversity was found in both species, with Simpson’s diversity index ranging from 0.817 to 0.968 in the studied populations. Moran’s I indices of multilocus genotypes in the studied populations, calculated by means of a Gabriel map, were higher than expected, which indicates that the spatial autocorrelation of clones was positive in each population. Comparatively, the value of Moran’s I ( I = 0.210∼0.354) for the S. pygmaea population was higher than that for the S. trifolia population. The change in Moran’s I with different distance classes in each population revealed differences in the features of clonal dispersal in the two species: the ramets of each clone preferably distributed in a limited area in populations of S. pygmaea , whereas there was the potential for long-distance spread for the ramets of S. trifolia . The authors deduced that the spatial autocorrelation of multilocus genotypes should be directly related to the clonal growth modes of the species. [ABSTRACT FROM AUTHOR]

Genetic differentiation in the Chilean blue mussel Mytilus chilensis (Hupé 1854) was investigated based on the variation in the allozyme frequencies of Pgm, Gpi, Icd, Me, Gsr, Lap and Pep in eight samples collected along 1800 km from Arauco (VIII Region) to Punta Arenas (XII Region). Despite the large geographic separations, values of Neis unbiased genetic distance, D (0.004-0.048) and standardised genetic variation among populations, Fst (0.011-0.055) were small. The levels of gene flow (Nm = 8) found in this study prevent the effect of differentiation among populations by genetic drift. This findings indicate that its long-lived planktotrophic larvae provides this species with considerable dispersal ability throughout its range which is favoured by the ocean currents along the chilean coast. In terms of management of the M. chilensis fishery, the results provide no evidence for discrete stocks, with the possible exception of the Punta Arenas population. Considering the intensive aquaculture activities with this species the present study provide preliminary data which can be used as a baseline for further characterization and /or monitoring these mussel populations.

The objectives of this work were to optimize the isozyme electrophoresis technique for Bixa orellana, and use isozyme markers for a preliminary survey on the genetic variability in Brazilian annatto germplasm accessions. Collection consisted of seed samples from sixty open pollinated trees, representing two Northern and four Southern geographic provenances. The extraction, electrophoresis, and interpretation of annatto isozymes are described. Three out of the twenty-one identified isozyme loci were polymorphic in the collection. The percentage of polymorphic loci (P = 21.05) and the expected heterozygosity in annatto (H T = 0.064) were low, compared to other tropical woody species. A UPGMA phenogram, constructed with Nei's genetic distances, clearly separated the germplasm provenant from North and Central Brazil. Variability was significantly higher among the accessions from Maranhão. A sharp genetic differentiation was detected between accessions from Maranhão and Pará States, despite their geographical proximity. The distinctive isozyme polymorphism, observed in the accessions from Maranhão, together with reports on local morphological heterogeneity in annatto fruit shape, color, and pubescence, calls for more detailed genetic and taxonomic investigation.Os objetivos deste trabalho foram: otimizar a técnica de eletroforese de isoenzimas para Bixa orellana, e usar marcadores isoenzimáticos para um estudo preliminar da variabilidade genética, presente em uma coleção de germoplasma de urucum. Foi estudada uma coleção de amostras de sementes oriundas de 60 indivíduos de polinização aberta, que representam duas procedências do Norte e quatro do Sul do Brasil. São descritas a extração, a eletroforese e a interpretação de isoenzimas de urucum. Três, dos vinte e um locos isoenzimáticos identificados, foram polimórficos na coleção examinada. A porcentagem de locos polimórficos (P = 21,05) e a heterozigosidade esperada em urucum (H T = 0,064) foram baixas, em comparação com outras espécies arbóreas tropicais. O dendrograma UPGMA, construído com base nas distâncias genéticas de Nei, diferenciou claramente as procedências de urucum do Norte, daquelas oriundas do Brasil Central. A variabilidade foi significativamente superior na procedência Maranhão. Uma pequena diferenciação genética foi detectada entre os acessos do Maranhão e do Pará, apesar da proximidade geográfica. O polimorfismo isoenzimático diferenciado, observado no germoplasma procedente do Maranhão, somado a relatos de heterogeneidade morfológica local com relação à forma, à cor e à pubescência dos frutos de urucum, sugerem uma investigação genética e taxonômica mais detalhada dessa espécie.

Genetic equilibrium of polymorphic enzyme loci from four natural populations of Cheilosia vernalis (Fallén, 1817) was tested. The study populations were from different regions of the Balkan Peninsula: Mediterranean area (Morinj, Montenegro: CVMOR), low mountain in the Pannonian plain (Fruška Gora, Serbia: CVFG), and two high Dinaric mountains (Durmitor, Montenegro CVDUR; and Kopaonik, Serbia: CVKOP). Out of twelve enzyme loci analyzed for genetic variability, only four to six were polymorphic in the studied populations. For those loci, the observed and expected values of genotype frequencies were compared with chi-square goodness-of-fit tests. Analysis of deviations of phenotypic classes from Hardy-Weinberg equilibrium revealed significant differences at polymorphic loci of all populations except in CVKOP. This implied possible important influence of evolutionary mechanisms such as low migration rates, population substructuring and natural selection in creation and maintenance of genetic variability.

Allozyme variability of populations of Merodon avidus A (M i l a n - k o v et al., 2001) from Dubašnica Mountain (Serbia), Morinj Bay (Montenegro) and Pindos Mountain (Greece) was analysed. The influence of gene flow on genetic differentiation among populations from the three biogeographical regions was also investigated. Genetic differentiaiton quantified by the Fst value, which is an inverse function of gene flow between populations, seemed to be correlated to both geographic and genetic distance (D, N e i, 1978), Namely in the population pairs Morinj - Dubašnica (253 km air distance), Morinj - Pindos (390km air distance) genetic differentiation and genetic distance increased with the geographic distance (Fst = 0.133, D = 0.022 and Fst = 0.309, D = 0.052, respectively). The exception was the population pair Dubašnica - Pindos (500 km air distance), where a lower degree of genetic differentiation was observed (Fst = 0.266; D = 0.047) than was expected based solely on the geographic distance. Results of this study suggest that that genetic differentiation among conspecific populations depends not only on the number of migrants (i. e. gene flow), but also on different selection pressure in different habits.

One of the possible reasons for pheasant population number decline in past several years might be loss of adaptability in populations originated from breeding stations caused by inbreeding depression. Due to fact that adaptability is a consequence of genetic structure of the populations, the aim of this paper was the analysis of genetic variability in pheasant population from breeding station Ristovaca using molecular markers. Allozyme variability of 20 putative gene loci was detected by polyacrylamide gel electrophoresis. Polymorphism was revealed in 5 loci: Est-1, Pgd, Sod, Gpi-2 and Odh. The values of genetic variability measures - heterozigosity polymorphism, fixation indices and H/P ratio indicate low level of genetic variability and possible presence of inbreeding depression within pheasant population.

The genetic differentiation of Solea solea and Solea senegalensis from several estuarine systems along the Portuguese coast was studied. Nine polymorphic isozyme loci (ACP-1*, ACP-2*, GPI-1*, GPI-2*, sMDH*, ME-1*, ME-2*, MPI* and PGM*) were analysed using starch gel electrophoresis and isoelectric focusing. Differentiation between the species was high (mean average Nei distance of 0.93). The most efficient loci in the diagnosis of the two species were ACP-1*, ME-2* and GPI-2*. S. solea showed a higher genetic diversity than S. senegalensis. Within each species a low genetic differentiation between the samples analysed was found. Although with a low magnitude the interpopulational genetic differentiation of S. solea was higher than that of S. senegalensis. This could probably be explained by some particularities of the life cycles of these species, namely the more extended period of occurrence of larval stages of S. senegalensis in the plankton. Although no clear evidence about the population structure model emerged from the analysis of several Atlantic and Mediterranean populations of S. solea, the significant correlations obtained between genetic and geographical distances support an isolation by distance model.

Arvicoline rodents serve as model organisms for investigating the intricacies of ecological/evolutionary feedbacks that characterize multiannual fluctuations in abundance. A population of California voles (Microtus californicus) in central California was followed for 3.5 years using 4 small grids located 50 m apart. Blood samples were scored for 4 polymorphic allozyme loci by starch gel electrophoresis. These were carefully chosen for their potential to reveal details of genetic structuring among demes. A low density of voles developed into a peak followed by a rapid decline to low density. Heterozygosity averaged 20.2% (n = 709) with loci-specific shifts associated with density, season, and cyclic phase. Statistically significant heterogeneity in genotypic and allelic frequencies among the grids was found for 3 of the loci. Pairwise comparisons among the grids for each locus separately (n = 24) yielded 11 significantly disparate pairs for genotypic frequencies and 10 for alleles. Significant correlations with cyclic phase were found at 1 locus (leucine aminopeptidase). Spatial differentiation among grid pairs (FST) ranged up to a 12-fold difference. FST values stratified by cyclic phase showed the highest levels in the pre-high phase and the lowest in the postpeak. A "founder/lush" model with sequential phases of semi-isolated low-density demes followed by panmixia at high densities, and then a density crash is supported. This pattern is postulated to facilitate adaptive evolution. [ABSTRACT FROM AUTHOR]

The selectivity of certain benzophenones and their carbonyl N-analogues was investigated towards the human GSTP1-1 allozymes A, B and C involved in MDR. The allozymes were purified from extracts derived from E. coli harbouring the plasmids pEXP5- CT/ TOPO- TA- hGSTP1*A, pOXO4- hGSTP1*B or pOXO4- hGSTP1*C. Compound screening with each allozyme activity indicated three compounds with appreciable inhibitory potencies, 12 and 13 with P1-1A 62% and 67%, 11 and 12 with P1-1C 51% and 70%, whereas that of 15 fell behind with P1-1B (41%). These findings were confirmed by IC50 values (74-125 μ m). Enzyme inhibition kinetics, aided by molecular modelling and docking, revealed that there is competition with the substrate CDNB for the same binding site on the allozyme ( Ki(13/A) = 63.6 ± 3.0 μ m, Ki(15/B) = 198.6 ± 14.3 μ m, and Ki(11/C) = 16.5 ± 2.7 μ m). These data were brought into context by an in silico structural comparative analysis of the targeted proteins. Although the screened compounds showed moderate inhibitory potency against hGSTP1-1, remarkably, some of them demonstrated absolute isoenzyme and/or allozyme selectivity. [ABSTRACT FROM AUTHOR]