Legacies of ancient riverine systems are often manifest in patterns of genetic diversity within aquatic species. The ancient Teays River, a principal drainage of the eastern United States, engaged in several ephemeral connections with neighboring palaeodrainages prior to and during the Pleistocene, when cyclical glacial advance and retreat reconfigured the region's fluvial systems. This study assayed DNA-sequence diversity at one mitochondrial (mtDNA) and three single-copy nuclear DNA (scnDNA) loci from the Tonguetied Minnow (Exoglossum laurae), a species distributed as four disjunct populations, one each within the Upper Great Miami, Upper Allegheny, Upper Genesee, and New rivers. Mitochondrial DNA variation revealed that the New River harbors the highest diversity (h = 0.73) and that the Tonguetied Minnow is composed of two ancient lineages, a Teays River lineage and a Pittsburgh River lineage. Analyses of the scnDNA loci revealed sharing of alleles among populations of E. laurae and between the Tonguetied Minnow and its only congener, the Cutlip Minnow (E. maxillingua), sampled from the Roanoke and Potomac rivers. The probability of interspecific hybridization in the New and Upper Genesee rivers was estimated as 0.16 and 0.34, respectively, but it is likely that some degree of incomplete lineage sorting contributed to these estimates. Probabilities of interspecific hybridization for Cutlip Minnow were 0.62 and 0.65, for the Roanoke and Potomac rivers, respectively, and might reflect ancient hybridization resulting from stream capture events involving these drainages by the Teays River. Management strategies should focus on maintaining the security of the Pittsburgh River lineage in the Upper Great Miami and Upper Allegheny River drainages. Finally, insights into the Tonguetied Minnow's rather convoluted taxonomic history are few, but genetic variation is inconsistent with subspecies status for Tonguetied Minnow in the Upper Great Miami River drainage.

Sport fisheries are frequent drivers of nonnative fish introductions throughout the inland waters of North America. These fisheries often value aggressive, large-bodied predators, and although they satiate angling demand they are also potentially problematic in systems that support imperiled species. The Tonguetied MinnowExoglossum lauraeis a rare species that maintains a disjunct distribution across small portions of four watersheds in the eastern and Midwestern United States, all of which are stocked with nonnative Brown TroutSalmo truttafor sportfishing. This study estimated habitat preferences for Tonguetied Minnow and Brown Trout in the Great Miami River, the westernmost drainage within the Tonguetied Minnow's range. Model data were based on eight water quality variables and seven stream habitat variables. Negative binomial regressions identified gradient, maximum water temperature, substrate, pool/glide habitat, total dissolved solids, and specific conductance as important predictors of the distribution of Tonguetied Minnow, whereas maximum water temperature and substrate were identified for Brown Trout. These reduced numbers of variables then served as input into maximum entropy species distribution models for Tonguetied Minnow and Brown Trout. Only gradient (model contribution [MC] = 46.9%; permutation importance [PI] = 11.6%) and maximum water temperature (MC = 44.2%; PI = 79.8%) contributed substantially to the species distribution model for Tonguetied Minnow, while maximum water temperature (MC = 63.4%; PI = 76.2%) and substrate (MC = 36.6%; PI = 23.8%) were important contributors for Brown Trout. Water temperature appears to exert the principal influence on the distributions of both species and supports the premise that these species share similar habitat preferences within the Great Miami River. Therefore, the Tonguetied Minnow is likely unable to avoid interspecific interactions, such as predation, posed by Brown Trout that are introduced for sportfishing, thus raising concerns about the conservation of this isolated and highly imperiled population.

Loss of wetlands throughout the southeastern United States threatens the persistence of the region's highly diverse freshwater fauna. Losses are especially concerning for rare species that maintain small or fragmented ranges, zoogeographies that characterize many of the region's numerous freshwater endemics. We assayed nuclear and mitochondria' DNA sequence data from the Pine Barrens Treefrog (Hyla andersonii), a rare species distributed across the Atlantic and Gulf coastal plains. We hypothesized that the species' evolutionary history has been associated with changes in wetlands during Quaternary interglacials and that the contemporaneous extent of wetlands is positively correlated with population genetic diversity. Genetic variation was highest in North Carolina and South Carolina and lowest in New jersey and Florida. Mean times to common ancestry ranged from 132,486 to 1,290,605 yr before present, and effective sizes ranged from 4,241 individuals in New Jersey to 403,718 individuals in North Carolina. Population migration rates were generally very low (<0.01), although higher rates were found between North Carolina and South Carolina. Total area of wetlands varied from 2,482 km(2) in South Carolina to 7,384 km(2) in North Carolina and has declined between 2001 and 2016. Genetic diversity was positively, although nonsignificantly, correlated to total amount of wetland habitat. Pine Barrens Treefrog is comprised of four relictual populations associated with ecological changes driven by climatic progressions of Quaternary interglacials, and collectively these populations conform to an abundant center model of evolution. All populations are conservatively designated management units, although evolutionarily significant unit status cannot be discounted.

Mislabeled commercial seafood products are pervasive, worldwide problems that threaten public health, undermine fisheries conservation efforts, and ultimately, lead to consumer financial loss. Although it can be unintentional, deliberately mislabeling of products is a more common trend used to increase profits and/or bypass fishing regulations, both of which are forms of fraud. Unfortunately, oversight, enforcement, and applied research remain insufficient relative to the global scale of the problem. To contribute to a currently small knowledge base on mislabeling rates in European markets, DNA sequence-based barcoding was applied to tissue samples from commercial products and restaurant offerings labeled as Atlantic cod (Gadus morhua) in Spain. Atlantic cod samples (n = 546) were collected from local markets, supermarkets, and restaurants from eight cities (Madrid, Salamanca, Santiago de Compostela, Bilbao, Barcelona, Valencia, Granada, and Seville). DNA barcoding used PCR-based assays of the mitochondrial cytochrome oxidase-I (COI) and 16S rRNA loci. A 6.2% mislabeling rate (34/546 samples) was discovered. There was no evidence of distinct geographic patterns of mislabeling, although tissue samples obtained from restaurants were more likely to be mislabeled than those sampled in markets and supermarkets. Processed forms of product (prepared, salted/smoked) were more likely to be mislabeled than fresh or frozen products. Common ling (Molva molva), haddock (Melanogrammus aeglefinus), saithe (Pollachius virens), and Alaskan pollock (Gadus chalcogrammus) were the most common substitutes, while Nile perch (Lates niloticus) and striped catfish (Pangasianodon hypophthalmus) were the most taxonomically dissimilar to Atlantic cod.

Invasive species threaten native taxa with extirpation and extinction via several biological mechanisms. One such mechanism, hybridization and subsequent introgression of invasive alleles into native genomes is a serious concern, especially for taxa displaying weak reproductive barriers, as is the case for black basses. Black basses introduced outside of their native ranges thus pose elevated threats to endemic congeners, particularly in the southern United States where restricted ranges preclude refuge from introgression. The recently delineated Bartram’s bass (M. sp. cf M. coosae) is endemic to the upper regions of the Savannah River basin, throughout which anthropogenic modification, including impoundment, has been extensive. Non-native Alabama bass (M. henshalli) and smallmouth bass (M. dolomieu) have been introduced into this system on multiple occasions and now threaten Bartram’s bass via introgression. In this study we sampled four reservoirs (Jocassee, Keowee, Hartwell, and Russell) in the upper Savannah River during 2004 and 2010. Results from three codominant nuclear loci and one mitochondrial locus revealed extensive introgression between Alabama and Bartram’s bass. Results show that Alabama bass have replaced Bartram’s bass in lakes Keowee and Russell, where they were first introduced, while the frequencies of hybrids in lakes Jocassee and Hartwell are increasing. Hybridization involving Bartram’s bass with native largemouth bass and introduced smallmouth bass was detected in very low frequencies. Results highlight the importance of continual study over geographic and temporal scales to inform management and conservation of rare fishes threatened with extinction via interspecific hybridization.

The highly diverse freshwater ichthyofauna of the southeastern United States' Atlantic slope is imperiled due to numerous anthropogenic insults to the region's lotic environments. Damming, pollution, riparian destruction, and introductions of nonnative species have all contributed significantly to reductions in freshwater biodiversity. Bartram's Bass (an as yet unnamed species similar to Redeye Bass Micropterus coosae), endemic to the Savannah River, is threatened with extirpation from multiple basin provinces via hybridization with introduced nonnative Alabama Bass M. henshalli and Smallmouth Bass M. dolomieu. Estimation of evolutionary and demographic parameters is critical to formulation of management plans designed to conserve this rare Atlantic slope endemic. Here we utilize analyses of DNA sequences from mitochondrial and nuclear loci to examine evolutionary patterns displayed by Bartram's Bass. Phylogenetic reconstructions and genetic variance partitioning revealed appreciable levels of population structure throughout the Savannah River basin, and exact tests of population differentiation identified several management units. Coalescent analyses returned mean effective population sizes (N-e) for extant populations ranging from 415 to 3,228 individuals (median range 388-2,531 individuals), rather recent times since population separation within the drainage (mean range 999-73,282 years before present; median range 493-65,417 years before present), and high population migration rates (2N(e)m > 1) among higher-latitude provinces, particularly the upper Savannah and Seneca rivers. Estimates of phylogenetic and demographic parameters, taken in conjunction with introgression of nonnative alleles resulting from micropterid introductions into the Savannah River, present the need for a comprehensive, basinwide conservation strategy to ensure the long-term in situ preservation of Bartram's Bass.

Shoal basses are a cryptic clade composed of Micropterus spp. restricted to the Apalachicola River system and three southeastern Atlantic slope river drainages in the southeastern United States. This reciprocally monophyletic clade includes the Shoal Bass M. cataractae (endemic to the Apalachicola River system), the Chattahoochee Bass M. chattahoochae, and two undescribed forms from the Altamaha, Ogeechee, and Savannah River drainages. Members of the shoal bass clade can be distinguished from all other species of Micropterus basses using 20 diagnostic characters (characteristic attributes) found in mitochondrial DNA (NADH dehydrogenase subunit 2) gene sequences. Each member of the clade additionally possesses unique characteristic attributes, which along with morphological and meristic characters can be used to diagnose this cryptic biodiversity. Biologists and managers have previously regarded the shoal basses in the Chattahoochee, Savannah, Altamaha and Ogeechee River systems as belonging to a single taxon synonymous with the Redeye Bass M. coosae, which is endemic to the Mobile River drainage. With these and previous analyses (including description of the Shoal Bass), we now recognize that what was once considered a single taxon actually comprises seven species, each of which is endemic to a single southeastern drainage. Recognizing and documenting the actual diversity of Micropterus spp. provides important information for managers who may wish to avoid stocking or translocations that could compromise the genetic integrity of native bass populations. Introductions of nonnative basses, including Alabama Bass M. henshalli, Spotted Bass M. punctulatus, and Smallmouth Bass M. dolomieu currently threaten the integrity of native shoal bass species in streams of the Chattahoochee, Altamaha, Ogeechee, and Savannah River systems.

Bartram's Bass (an as yet unnamed species similar to Redeye Bass Micropterus coosae) is endemic to the Savannah drainage of South Carolina and Georgia. Hybridization between this native species and introduced Alabama Bass M. henshalli is widespread in the upper portions of the drainage. Recent studies have documented a precipitous decline in genetically pure Bartram's Bass in Savannah drainage reservoirs and a corresponding increase in fish of hybrid origin. We surveyed tributary populations associated with these reservoirs and with the Savannah River main stem in 2004 and 2010. Results indicate an increased occurrence of hybrids in Bartram's Bass native stream habitats over time. We also document the new occurrence of a second nonnative species, Smallmouth Bass M. dolomieu. Both Smallmouth Bass and their hybrids with Bartram's Bass were collected from shoals in the Savannah River near the lower extent of the Bartram's Bass range. Bartram's Bass is a species of highest conservation concern in South Carolina, due to its limited native range and threats associated with hybridization. Conservation actions directed at this species, and its native stream habitats, will need to consider the establishment of nonnative species in the drainage and their potential to impact tributary populations over time.

INTRODUCTION The earth's biota is in the middle of its most severe rate of decline since the end of the Cretaceous, the period that encompassed the extinction of the dinosaurs roughly sixty-five million years ago (Glavine). Numerous anthropogenic practices have contributed significantly to these losses in biodiversity (Eldredge; Novacek and Cleland). For instance, habitat reductions as a result of expanding human land use (Franklin; Sala et al.; Harte; Falcucci et al.), environmental degradation due to pollution (Barker and Tingey; McNeely), introduction and establishment of non-native species (Wilcove et al.; Sala et al.), and climate change (Lovejoy and Hannah) are among the factors known to have contributed to declines in biodiversity. Alarmingly, results of at least one survey have revealed that the American public does not rank this biodiversity crisis highly (Novacek) despite the many negative consequences associated with significant reductions in biodiversity (Chapin et al.; Worm et al.). Several methodologies have been proposed to mitigate, halt, or even reverse losses in biodiversity (Johns; Novacek). Of these, education that conveys the importance of biodiversity to human subsistence is one particularly effective approach (Caro et al.; Braus; Bonine et al.; Brewer; Jacobson et al.). At the post-secondary level, biodiversity education is primarily the responsibility of a few closely-related scientific departments such as biology, natural resources, ecology, and environmental sciences. This restricted focus is not unexpected since biodiversity is a discipline that falls squarely under the purview of the natural sciences (see Takacs, 1996). However, in addition to its deep biological roots, biodiversity routinely traverses legal (Keiter; Glowka), political (Thomas; Boardman), economic (Chopra; Swanson; Johnson et al.), ethical (Tilman; Clark), and social (Takacs; Peine) arenas. Thus, comprehensive studies in biodiversity and its conservation require at least a cursory understanding of several highly varied academic disciplines (Van Dyke). Such a holistic presentation of diverse academic disciplines may present a significant challenge to individual instructors, many of whom have spent their careers acquiring expertise in a single, narrowly focused field of study. The multifaceted nature of biodiversity and conservation lends itself nicely to honors programs. Among other goals, honors seeks to provide for its students a multidisciplinary educational experience that furthers the core mission of a program. For example, at Northern Kentucky University, our honors program emphasizes four central domains: 1) active learning 2) global citizenship, 3) civic engagement, and 4) undergraduate research. We will demonstrate the ease with which biodiversity and conservation education can align with these four domains and with the multidisciplinarity and values-based mission of honors. While we use the NKU Honors Program as an example, we hope that readers readily and easily extend this example to their own honors programs, departments, or colleges. We attempt to highlight how the myriad of academic expertise typically housed within honors programs readily promotes and addresses biodiversity and conservation education. FOUR DOMAINS OF HONORS SCHOLARSHIP DOMAIN 1: ACTIVE LEARNING Partly due to the appeal of understanding biodiversity through diverse lines of study, it has been our experience that students readily participate in lively classroom debates and discussions concerning the many disciplines spanned by issues of biodiversity and conservation. Specifically, students engage their fellow classmates and instructor when asked to contextualize and couch conservation and biodiversity within their own major field of study, fueling active learning and promoting student interest. For example, finance majors may explore the economic values underlying the preservation of biodiversity while a political science student may investigate the policies that underlie effective management of imperiled species whose distributions span multiple boundaries between, for instance, states and nations. …

INTRODUCTION The earth's biota is in the middle of its most severe rate of decline since the end of the Cretaceous, the period that encompassed the extinction of the dinosaurs roughly sixty-five million years ago (Glavine). Numerous anthropogenic practices have contributed significantly to these losses in biodiversity (Eldredge; Novacek and Cleland). For instance, habitat reductions as a result of expanding human land use (Franklin; Sala et al.; Harte; Falcucci et al.), environmental degradation due to pollution (Barker and Tingey; McNeely), introduction and establishment of non-native species (Wilcove et al.; Sala et al.), and climate change (Lovejoy and Hannah) are among the factors known to have contributed to declines in biodiversity. Alarmingly, results of at least one survey have revealed that the American public does not rank this biodiversity crisis highly (Novacek) despite the many negative consequences associated with significant reductions in biodiversity (Chapin et al.; Worm et al.). Several methodologies have been proposed to mitigate, halt, or even reverse losses in biodiversity (Johns; Novacek). Of these, education that conveys the importance of biodiversity to human subsistence is one particularly effective approach (Caro et al.; Braus; Bonine et al.; Brewer; Jacobson et al.). At the post-secondary level, biodiversity education is primarily the responsibility of a few closely-related scientific departments such as biology, natural resources, ecology, and environmental sciences. This restricted focus is not unexpected since biodiversity is a discipline that falls squarely under the purview of the natural sciences (see Takacs, 1996). However, in addition to its deep biological roots, biodiversity routinely traverses legal (Keiter; Glowka), political (Thomas; Boardman), economic (Chopra; Swanson; Johnson et al.), ethical (Tilman; Clark), and social (Takacs; Peine) arenas. Thus, comprehensive studies in biodiversity and its conservation require at least a cursory understanding of several highly varied academic disciplines (Van Dyke). Such a holistic presentation of diverse academic disciplines may present a significant challenge to individual instructors, many of whom have spent their careers acquiring expertise in a single, narrowly focused field of study. The multifaceted nature of biodiversity and conservation lends itself nicely to honors programs. Among other goals, honors seeks to provide for its students a multidisciplinary educational experience that furthers the core mission of a program. For example, at Northern Kentucky University, our honors program emphasizes four central domains: 1) active learning 2) global citizenship, 3) civic engagement, and 4) undergraduate research. We will demonstrate the ease with which biodiversity and conservation education can align with these four domains and with the multidisciplinarity and values-based mission of honors. While we use the NKU Honors Program as an example, we hope that readers readily and easily extend this example to their own honors programs, departments, or colleges. We attempt to highlight how the myriad of academic expertise typically housed within honors programs readily promotes and addresses biodiversity and conservation education. FOUR DOMAINS OF HONORS SCHOLARSHIP DOMAIN 1: ACTIVE LEARNING Partly due to the appeal of understanding biodiversity through diverse lines of study, it has been our experience that students readily participate in lively classroom debates and discussions concerning the many disciplines spanned by issues of biodiversity and conservation. Specifically, students engage their fellow classmates and instructor when asked to contextualize and couch conservation and biodiversity within their own major field of study, fueling active learning and promoting student interest. For example, finance majors may explore the economic values underlying the preservation of biodiversity while a political science student may investigate the policies that underlie effective management of imperiled species whose distributions span multiple boundaries between, for instance, states and nations. …

DNA sequence variation at a mitochondrial and a nuclear intron locus was surveyed within and among multiple populations of the inland silverside (Menidia beryllina) from the southeastern United States and revealed discordant phylogenetic patterns but similar patterns of population genetic variation across nuclear and mitochondrial loci. Mitochondrial variation was geographically structured, with strongly supported monophyletic assemblages among Gulf of Mexico population samples and a close association of the St John's River (SJ) population with these same samples. Nuclear alleles were not strongly structured geographically, with little support for monophyly within or across basins. Conversely, population genetic parameters indicate that the bulk of genetic diversity for both genomes resides within and among Gulf of Mexico populations and that diversity within the Atlantic is largely restricted to the SJ population. The contrast in genetic variation and population phylogenies appears to be a function of historical demographic processes, most likely directed by fluctuating geomorphology of the Florida peninsula in response to North American glaciation cycles.

Comparing variation across evolutionarily independent characters, notably nuclear and mitochondrial genes, yields a more robust estimate of diversification than is generally recovered from individual characters. Patterns of variation across multiple molecular markers from the mitochondrial (16SrRNA, cytochrome b) and nuclear (ldhA6 and aldB) genomes were examined from six populations of Etheostoma collis and two populations of Etheostoma saludae, species aligned in the collis groups. Phylogenetic analyses revealed that sequence variation among individuals from the Roanoke, Tar and Neuse Rivers and the Catawba and Pee Dee Rivers, respectively, form highly supported, deeply divergent clades. Relationships of alleles sampled from Saluda River E. saludae and Cape Fear River E. collis to these lineages are unresolved, but all groups are reciprocally monophyletic for both nuclear and mtDNA loci. Phylogenetic analyses suggest that historical factors have had a strong influence on the distribution of genetic variation among populations. Genetic variation within the collis group is consistent with all previously proposed taxonomic hypotheses for the collis group, providing no taxonomic insights. From a conservation standpoint, each population of the collis group is an ESU, thereby warranting a drainage-specific management strategy.

On 26 June 2006 an aggregation of 16 whale sharks was observed for a period of 4 hr in the north centra!Gulf of Mexico (GOM).The sharks remained within an area about 1.0 lan 2 in size aod continuously ram filter fed at the surface.Visual analysis of a plankton sample collected from the study site revealed the presence of copious amounts of fish eggs in mid-embryonic development and a minor amount of other zooplankton.A second plankton sample (control) collected about 3.5 Ian from the study site in an area where no whale sharks were present contained few eggs, however other zooplankton were similar to the study site sample in species composition aod abuodance.1\vo egg morphs were identified, and samples of one of the morphs, which represented 98% of the eggs at the study site, were verified by genetic analysis as little tunny, Euthynnus alleteratus.The observed feeding behavior aod the abuodance of fish eggs at the study site indicated the whale sharks were feeding on recently spawned little tunny eggs.This represents the first confirmed observation of a feeding aggregation of whale sharks in theGOM.RESUMEN El 26 de Junio del 2006 un agrupamiento de 16 tiburones ballena fue observado por un periodo de 4 horas en el centro norte del Golfo de M6jico (GOM).Los tiburones permanecieron dentro de un i!rea altededor de 1.0 lan 2 y continuamente se desplazaron filtrando alimento en la superficie.Un anaJisis visual de una muestra de plankton colectada en el sitio de estudio revela la presencia de grandes cantidades de huevos de peces en un desarrollo intermedio del embri6n y una pequella cantidad de otro zooplancton.En un i!rea donde no hablan tiburones ballena, una segunda muestra de plancton (control) colectada (alrededor de 3.5 Ian.del sitio de estudio) presento pocos huevos de peces, sin embargo el otro zooplancton fue similar en composici6n de especies y abundancia con la muestra colectada en el sitio de estudio.Dos formas de huevos fueron identificadas, la fonna que represento el 98% de los huevos en el sitio de estudio fue identificada mediante un anaJisis gen6tico como bacoreta, Euthynnus alleUeratus.EI comportamiento de alimentaci6n observado y la abundancia de huevos de peces en el cirea de estudio indicaron que los tiburones ballena se alimentaron de un desove de huevos reciente de bacoreta.. Esto representa la primera observaci6n confinnada de una agregaci6n de tiburones ballena en el GOM.

Keowee Reservoir has supported an abundant population of native Micropterus coosae (redeye bass) for over 30 years. Recently, redeye bass abundance in this reservoir declined concomitantly with the establishment of anglerintroduced Micropterus punctulatus henshalli (Alabama spotted bass). We suspected declines in redeye bass abundance may be related to their hybridizing with the Alabama spotted bass resulting in offspring that are difficult to differentiate from the Alabama spotted bass. Thus, we collected tissue for genetic analyses from what was thought to be pure redeye bass (Jocassee Reservoir, SC), the original source of Alabama spotted bass (Lake Lanier, GA) stocked in Lake Keowee, and suspected redeye bass x Alabama spotted bass hybrids (Keowee Reservoir, SC) to determine if hybridization might be occurring. These analyses confirmed that hybridization among species of Micropterus had occurred in Keowee Reservoir.

Background: Nuclear DNA sequences provide genetic information that complements studies using mitochondrial DNA. Some 'universal' primer sets have been developed that target introns within protein-coding loci, but many simultaneously amplify introns from paralogous loci. Refining existing primer sets to target a single locus could circumvent this problem.Results: Aldolase intron 'G' was amplified from four fish species using previously described primer sets that target several loci indiscriminately. Phylogenetic analyses were used to group these fragments and other full-length aldolase proteins from teleost fishes into orthologous clades and a primer set was designed to target specifically an intron within the aldolase-B locus in acanthopterygian fishes. DNA amplifications were tried in a variety of acanthopterygian fishes and amplification products, identifiable as aldolase-B intron 'G', were observed in all atherinomorph and percomorph taxa examined. Sequence variation within this locus was found within and among several species examined.Conclusions: Using 'universal' primer sets coupled with phylogenetic analyses it was possible to develop a genetic assay to target a specific locus in a variety of fish taxa. Sequence variation was observed within and among species suggesting that this targeted assay might facilitate interspecific and intraspecific comparisons.

Proposed mechanisms by which alpha 2-adrenergic receptors (alpha 2AR) regulate intracellular calcium ([Ca2+]i) include stimulation and inhibition of cell surface calcium channels, stimulation of calcium release via receptor coupling to Gq with subsequent activation of phospholipase C and release of IP3, or stimulation of calcium release via coupling to Gi in an IP3-independent manner. These potential mechanisms were explored in cells that expressed alpha(2A)AR endogenously (HEL cells), permanently transfected CHO cells, and transiently transfected COS-7 cells. Each cell type displayed agonist (UK14304)-dependent increases in [Ca2+]i that were blocked by yohimbine, ablated by pertussis toxin, and largely unaffected by chelation of extracellular calcium. Furthermore, calcium release was associated with IP3 accumulation and was blocked by an inhibitor of phospholipase C (PLC). When expressed in CHO cells, a mutated alpha(2A)AR which has the amino and carboxyl termini of the third intracellular loop substituted with beta 2AR sequence poorly coupled to Gi in adenylyl cyclase assays, and likewise displayed virtually no coupling to increased [Ca2+]i. These results all point toward a Gi- versus a Gq-mediated coupling pathway triggering release of intracellular calcium stores. The possibility that G(beta gamma) subunits released from alpha(2A)AR-Gi coupling is the mechanism of PLC activation was explored in COS-7 cells by coexpressing alpha(2A)AR with the G(beta gamma) inhibitors transducin or a carboxy-terminal portion of the beta AR kinase. Both beta gamma inhibitors markedly inhibited alpha(2A)AR modulation of [Ca2+]i while not affecting thromboxane A2 receptor mediated stimulation of [Ca2+]i via Gq coupling. Thus, alpha(2A)AR couple to calcium release via Gi-associated G(beta gamma) subunits. This coupling is present in multiple cell types and should be considered a major signal transduction pathway of this receptor.

Two subspecies of largemouth bass, the northern largemouth bass (Micropterus salmoides salmoides) and the Florida bass (Micropterus salmoides floridanus) occur commonly throughout the southeastern United States. Prior to 1949 the Florida bass was known only from peninsular Florida; unfortunately, due to greater maximum size and longevity the Florida subspecies has been introduced into lakes and other impoundments throughout the east coast and southern United States. This expansion of Florida bass into the habitat of northern largemouth bass could result in hybridization of the two subspecies and thus may affect the fitness of the northern largemouth bass populations in these areas. We characterized genetic diversity at one mitochondrial locus (ND2) and four single copy nuclear loci (ITS2, Actin, S7, and Calmodulin). The resulting DNA sequences were used to create a genetic database useful for differentiating these two subspecies.