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B W Bowen

Publications and source records attributed to B W Bowen.

At least 19 recordsLinked to original sources
PubMed2007

Mixed-stock analysis reveals the migrations of juvenile hawksbill turtles (Eretmochelys imbricata) in the Caribbean Sea.

Hawksbill turtles (Eretmochelys imbricata) migrate between nesting beaches and feeding habitats that are often associated with tropical reefs, but it is uncertain which nesting colonies supply which feeding habitats. To address this gap in hawksbill biology, we compile previously published and new mitochondrial DNA (mtDNA) haplotype data for 10 nesting colonies (N = 347) in the western Atlantic and compare these profiles to four feeding populations and four previously published feeding samples (N = 626). Nesting colonies differ significantly in mtDNA haplotype frequencies (Phi(ST) = 0.588, P < 0.001), corroborating earlier conclusions of nesting site fidelity and setting the stage for mixed-stock analysis. Feeding aggregations show lower but significant structure (Phi(ST) = 0.089, P < 0.001), indicating that foraging populations are not homogenous across the Caribbean Sea. Bayesian mixed-stock estimates of the origins of juveniles in foraging areas show a highly significant, but shallow, correlation with nesting population size (r = 0.378, P = 0.004), supporting the premise that larger rookeries contribute more juveniles to feeding areas. A significant correlation between the estimated contribution and geographical distance from nesting areas (r = -0.394, P = 0.003) demonstrates the influence of proximity on recruitment to feeding areas. The influence of oceanic currents is illustrated by pelagic stage juveniles stranded in Texas, which are assigned primarily (93%) to the upstream rookery in Yucatan. One juvenile had a haplotype previously identified only in the eastern Atlantic, invoking rare trans-oceanic migrations. The mixed-stock analysis demonstrates that harvests in feeding habitats will impact nesting colonies throughout the region, with the greatest detriment to nearby nesting populations.

Animal Migration↗
PubMed2006

Shallow mtDNA coalescence in Atlantic pygmy angelfishes (genus Centropyge) indicates a recent invasion from the Indian Ocean.

Pygmy angelfishes (genus Centropyge) are widespread and species-rich in the Indo-Pacific, but only three species are recognized in the Atlantic: Centropyge resplendens on the Mid-Atlantic Ridge, Centropyge argi in the Caribbean, and Centropyge aurantonotus in Brazil and the southern Caribbean. Atlantic species are distinguished only by color patterns and are very similar to Centropyge acanthops (Cac) in the western Indian Ocean, raising the possibility that pygmy angelfish recently invaded the Atlantic Ocean via southern Africa. To test this zoogeographic hypothesis, we compared a 454-bp segment of the mitochondrial DNA (mtDNA) control region among pygmy angelfishes of the subgenus Xiphypops, which includes the three Atlantic species, the Indian Ocean species, and an Indo-Pacific species [Centropyge fisheri (Cfi)]. The Indian Ocean species Cac is closest to the Atlantic species (d = 0.059) relative to Cfi (d = 0.077). The mtDNA genealogy indicates a colonization pathway from the Indian Ocean directly to the West Atlantic, followed by at least two waves of dispersal to the Mid-Atlantic Ridge. The gene tree for the three Atlantic species is polyphyletic, raising questions about taxonomic assignments based on color pattern. Mismatch distributions place Atlantic founder events and population expansions at about 250,000-500,000 years ago. Estimates of effective female population sizes from mismatch and coalescence analyses are consistent with founder events by tens of individuals in the western Atlantic, followed by expansions to several million individuals.

Animals↗
PubMed2006

Global phylogeography of the scalloped hammerhead shark (Sphyrna lewini).

Large marine fishes typically have little population genetic structure. The exceptions are associated with sedentary behaviour, disjunct distributions, or reproductive philopatry. Scalloped hammerhead sharks (Sphyrna lewini) incorporate the contrasting traits of oceanic habitat (usually associated with high dispersal) and possible fidelity to nursery grounds (for reproductive females). To evaluate the expectations of these contrasting behaviours, we examined the global genetic structure of S. lewini based on collections (n = 271 individuals) from 20 nursery areas. A 548-bp fragment of mitochondrial DNA control region revealed 22 polymorphic sites, 24 haplotypes, and three lineages distinguished by 2.56-3.77% sequence divergence. Coalescence analyses based on a provisional molecular clock indicate an origin in the Indo-West Pacific with late Pleistocene radiations into the central Pacific (Hawaii) and eastern Pacific (Central America), as well as recent interchange between oceans via southern Africa. Population subdivisions are strong (overall Phi(ST) = 0.749, P < 0.0001 and among oceans Phi(ST) = 0.598, P < 0.0098). Genetic discontinuity within oceans (Phi(ST) = 0.519, P < 0.0001) is primarily associated with oceanic barriers (migration across oceans M approximately 0), with much less structure along continental margins (M > 10). We conclude that nursery populations linked by continuous coastline have high connectivity, but that oceanic dispersal by females is rare. Although we cannot rule out philopatry to natal nurseries, oceanic barriers appear to have a much stronger influence on the genetic architecture of this species and may indicate a mechanism for recent evolutionary radiations in the genus Sphyrna.

Animals↗
PubMed2005

Conservation implications of complex population structure: lessons from the loggerhead turtle (Caretta caretta).

Complex population structure can result from either sex-biased gene flow or population overlap during migrations. Loggerhead turtles (Caretta caretta) have both traits, providing an instructive case history for wildlife management. Based on surveys of maternally inherited mtDNA, pelagic post-hatchlings show no population structure across the northern Atlantic (phi(ST) < 0.001, P = 0.919), subadults in coastal habitat show low structure among locations (phi(ST) = 0.01, P < 0.005), and nesting colonies along the southeastern coast of the United States have strong structure (phi(ST) = 0.42, P < 0.001). Thus the level of population structure increases through progressive life history stages. In contrast, a survey of biparentally inherited microsatellite DNA shows no significant population structure: R(ST) < 0.001; F(ST) = 0.002 (P > 0.05) across the same nesting colonies. These results indicate that loggerhead females home faithfully to their natal nesting colony, but males provide an avenue of gene flow between regional nesting colonies, probably via opportunistic mating in migratory corridors. As a result, all breeding populations in the southeastern United States have similar levels of microsatellite diversity (H(E) = 0.70-0.89), whereas mtDNA haplotype diversity varies dramatically (h = 0.00-0.66). Under a conventional interpretation of the nuclear DNA data, the entire southeastern United States would be regarded as a single management unit, yet the mtDNA data indicate multiple isolated populations. This complex population structure mandates a different management strategy at each life stage. Perturbations to pelagic juveniles will have a diffuse impact on Atlantic nesting colonies, mortality of subadults will have a more focused impact on nearby breeding populations, and disturbances to adults will have pinpoint impact on corresponding breeding populations. These findings demonstrate that surveys of multiple life stages are desirable to resolve management units in migratory marine species.

Analysis of Variance↗
PubMed2004

Living with uncertainty: genetic imprints of climate shifts in East Pacific anchovy (Engraulis mordax) and sardine (Sardinops sagax).

In the upwelling zone of the northeastern Pacific, cold nutrient-rich conditions alternate with warm nutrient-poor intervals on timescales ranging from months to millennia. In this setting, the abundances of Pacific sardine (Sardinops sagax) and northern anchovy (Engraulis mordax) fluctuate by several orders of magnitude, with sardine dominating during warm conditions and anchovy dominating during cool conditions. Two population models can explain the response of these fishes to adverse conditions. Under the basin model, species distributions contract to a central (optimal) range during population crashes. Expectations of this model may include a single range-wide population with a decline in genetic diversity on both sides of a central refuge. In contrast, the self-recruitment model invokes a series of local oceanographic domains that maintain semi-isolated subpopulations. During adverse conditions, some subpopulations cannot complete the life cycle within the local environment and are extirpated. Expectations of this model include some degree of population genetic structure and no clear gradient in genetic diversity. We examined mitochondrial DNA cytochrome b sequences to assess these competing models for anchovy (N = 196; 539 bp) and sardine (N = 107; 425 bp). The mitochondrial DNA gene genealogies are shallow but diverse for both species. Haplotype frequencies are homogeneous among subpopulations, but genetic diversities peak for both species along Baja California and adjacent southern California. Mismatch distributions and Tajima's D-values reveal distinctive signatures of population bottlenecks and expansions. Sardine haplotypes coalesce at approximately 241,000 years bp, with an initial female effective population size Nf0 = 0 followed by exponential growth to Nf1 = 115 million. Anchovy haplotypes coalesce at approximately 282,000 years bp, with an initial population size of Nf0 = 14,000, followed by exponential growth to Nf1 = 2.3 million. These results indicate a founder event for sardine and a severe population decline for anchovy in the California Current during the late Pleistocene. Overall, these data support the basin model on decadal timescales, although local recruitment may dominate on shorter timescales.

Animals↗
PubMed2001

Phylogeography of Ophioblennius: the role of ocean currents and geography in reef fish evolution.

Many tropical reef fishes are divided into Atlantic and East Pacific taxa, placing similar species in two very different biogeographic regimes. The tropical Atlantic is a closed ocean basin with relatively stable currents, whereas the East Pacific is an open basin with unstable oceanic circulation. To assess how evolutionary processes are influenced by these differences in oceanography and geography, we analyze a 630-bp region of mitochondrial cytochrome b from 171 individuals in the blenniid genus Ophioblennius. Our results demonstrate deep genetic structuring in the Atlantic species, O. atlanticus, corresponding to recognized biogeographic provinces, with divergences of d = 5.2-12.7% among the Caribbean, Brazilian, St. Helena/Ascension Island, Gulf of Guinea, and Azores/Cape Verde regions. The Atlantic phylogeny is consistent with Pliocene dispersal from the western to eastern Atlantic, and the depth of these separations (along with prior morphological comparisons) may indicate previously unrecognized species. The eastern Pacific species, O. steindachneri, is characterized by markedly less structure than O. atlanticus, with shallow mitochondrial DNA lineages (dmax = 2.7%) and haplotype frequency shifts between locations in the Sea of Cortez, Pacific Panama, Clipperton Island, and the Galapagos Islands. No concordance between genetic structure and biogeographic provinces was found for O. steincdachneri. We attribute the phylogeographic pattern in O. atlanticus to dispersal during the reorganization of Atlantic circulation patterns that accompanied the shoaling of the Isthmus of Panama. The low degree of structure in the eastern Pacific is probably due to unstable circulation and linkage to the larger Pacific Ocean basin. The contrast in genetic signatures between Atlantic and eastern Pacific blennies demonstrates how differences in geology and oceanography have influenced evolutionary radiations within each region.

Animals↗
PubMed2001

The evolutionary enigma of bonefishes (Albula spp.): cryptic species and ancient separations in a globally distributed shorefish.

Many examples of cryptic marine species have been demonstrated with biochemical and molecular studies. In most cases, a broadly distributed taxon is actually a group of sibling species that can be distinguished (upon closer examination) by ecological or morphological characters. Fishes of the family Albulidae constitute a notable exception. Bonefish (Albula spp.) morphology and ecology are highly conserved around the globe, and their extended pelagic larval stage could allow population connections on a vast geographic scale. Based on this perceived homogeneity, bonefishes were classified as a single pantropical species, A. vulpes. However, allozyme studies of Hawaiian populations indicated that two sympatric species (A. glossodonta and A. neoguinaica) are included in the synonymy of A. vulpes. To ascertain the number and distribution of evolutionary partitions in Albula, we surveyed 564 bp of mitochondrial DNA (mtDNA) cytochrome b from 174 individuals collected at 26 locations. Sequence comparisons reveal eight deep lineages (d = 5.56-30.6%) and significant population structure within three of the four lineages that could be tested (phiST = 0.047-0.678). These findings confirm the genetic distinctiveness of the three species noted above and invoke the possibility of five additional species. Clock estimates for mtDNA indicate that these putative species arose 4-20 million years ago. Distinct evolutionary lineages coexist in several sample locations, yet show little morphological or ecological differentiation in sympatry. Thus, bonefish species seem to defy the evolutionary conventions of morphological differentiation over time and ecological displacement in sympatry. Despite multiple cases of sympatry, sister-taxa relationships inferred from mtDNA indicate that divergence in allopatry has been the predominant speciation mechanism in Albula. Stabilizing selection in the homogeneous habitat occupied by bonefishes (tropical sand flats) could promote the retention of highly conserved morphology and ecology.

Animals↗
PubMed2000

Phylogeography of colonially nesting seabirds, with special reference to global matrilineal patterns in the sooty tern (Sterna fuscata).

Sooty tern (Sterna fuscata) rookeries are scattered throughout the tropical oceans. When not nesting, individuals wander great distances across open seas, but, like many other seabirds, they tend to be site-faithful to nesting locales in successive years. Here we examine the matrilineal history of sooty terns on a global scale. Assayed colonies within an ocean are poorly differentiated in mitochondrial DNA sequence, a result indicating tight historical ties. However, a shallow genealogical partition distinguishes Atlantic from Indo-Pacific rookeries. Phylogeographic patterns in the sooty tern are compared to those in other colonially nesting seabirds, as well as in the green turtle (Chelonia mydas), an analogue of tropical seabirds in some salient aspects of natural history. Phylogeographic structure within an ocean is normally weak in seabirds, unlike the pronounced matrilineal structure in green turtles. However, the phylogeographic partition between Atlantic and Indo-Pacific rookeries in sooty terns mirrors, albeit in shallower evolutionary time, the major matrilineal subdivision in green turtles. Thus, global geology has apparently influenced historical gene movements in these two circumtropical species.

Animals↗
PubMed2000

Systematic analysis of xanthomonads (Xanthomonas spp.) associated with pepper and tomato lesions.

The taxonomy and evolutionary relationships among members of the genus Xanthomonas associated with tomato and pepper have been a matter of considerable controversy since their original description in 1921. These bacteria, which are a major affliction of tomato and pepper crops in warm and humid regions, were originally described as a single species, but subsequent research has shown the existence of at least two genetic groups differentiated by physiological, biochemical and pathological characteristics. This work synthesizes the findings from several approaches, including pathogenicity tests, enzymic activity, restriction fragment analysis of the entire genome, DNA-DNA hybridization and RNA sequence comparisons based on a 2097 base sequence comprising the 16S rRNA gene, the intergenic spacer located between the 16S and 23S rRNA genes and a small region of the 23S rRNA gene. Within the group of xanthomonads pathogenic on pepper and tomato four distinct phenotypic groups exist, of which three form distinct genomic species. These include Xanthomonas axonopodis pv. vesicatoria (A and C group), Xanthomonas vesicatoria (B group) and Xanthomonas gardneri (D group). On the basis of phenotypic and genotypic differences between A- and C-group strains, the C strains should be considered as a subspecies within Xanthomonas axonopodis pv. vesicatoria.

Antibodies, Monoclonal↗
PubMed1999

Effects of natural habitat fragmentation on an endemic scrub lizard (Sceloporus woodi): an historical perspective based on a mitochondrial DNA gene genealogy.

The Florida scrub lizard, Sceloporus woodi, is endemic to scrub habitat patches along the central portion of the Florida peninsula and xeric coastal regions. Scrub ecosystems are the patchily distributed remnants of previously widespread habitats formed during the Pleiocene and early Pleistocene. Scrub lizards appear to have limited dispersal capabilities due to high habitat specificity and low mobility. To assess the population structure and phylogeography of S. woodi, 135 samples were collected from 16 patches on five major ridges in Florida, USA. Analysis of 273 bp of mitochondrial DNA (mtDNA) cytochrome b reveals a very strong geographic distribution of genetic diversity. Haplotype frequencies are significantly different in 63 of 66 comparisons between patches. With one exception, samples from the five major ridges are characterized by fixed differences in haplotype distribution and deep evolutionary separations (3-10%). Fixed genetic differences were also observed between northern and southern segments of several ridges. Analysis of molecular variance (AMOVA) shows an estimated 10.4% total genetic variation within patches, 17.5% among patches (within ridges), and 72.1% among ridges. This strong population structure among patches within ridges indicates that the distribution of S. woodi is tightly linked to sandy scrub habitat and that the discontinuous distribution of scrub habitats significantly inhibits dispersal and gene flow. Phylogeographic analyses indicate a pattern of dispersal down the Florida peninsula during the late Pliocene-early Pleistocene, followed by habitat fragmentation and variant isolation events. Therefore, the deep genetic structuring among scrub lizard populations on separate ridges is attributed to ancient isolation events induced by a shift from dry (xeric) to wet (mesic) conditions on the Florida peninsula. These findings indicate that some scrub lizard populations have persisted in isolation for time frames in excess of 1 Myr, providing a case history on the genetic consequences of habitat fragmentation.

Animals↗
PubMed1999

Preserving genes, species, or ecosystems? Healing the fractured foundations of conservation policy.

The scientific foundations of conservation policy are the subject of a recent tripolar debate, with systematists arguing for the primacy of phylogenetic rankings, ecologists arguing for protection at the level of populations or ecosystems, and evolutionary biologists urging more attention for the factors that enhance adaptation and biodiversity. In the field of conservation genetics, this controversy is manifested in the diverse viewpoints of molecular systematists, population biologists, and evolutionary (and quantitative) geneticists. A resolution of these viewpoints is proposed here, based on the premise that preserving particular objects (genes, species, or ecosystems) is not the ultimate goal of conservation. In order to be successful, conservation efforts must preserve the processes of life. This task requires the identification and protection of diverse branches in the tree of life (phylogenetics), the maintenance of life-support systems for organisms (ecology), and the continued adaptation of organisms to changing environments (evolution). None of these objectives alone is sufficient to preserve the threads of life across time. Under this temporal perspective, molecular genetic technologies have applications in all three conservation agendas; DNA sequence comparisons serve the phylogenetic goals, population genetic markers serve the ecological goals, quantitative genetics and genome explorations serve the evolutionary goals.

Animals↗
PubMed1998

Molecular phylogeny and biogeography of the marine shrimp Penaeus.

The evolutionary relationships among 13 species representing all six subgenera of the shrimp genus Penaeus were examined using 558 bp of mitochondrial (mt) DNA from the cytochrome oxidase subunit I gene. Analyses of this sequence revealed high genetic divergence between species (d = 8-24%), a finding which contrasts with previous work, which indicated that genetic diversity, based on electrophoretic analysis of allozymes, was extremely low in Penaeus. Three tree-building methods (maximum parsimony, neighbor joining, and maximum likelihood) were concordant in indicating that current subgenera assignments do not reflect evolutionary partitions within the genus Penaeus. While the molecular phylogenies cast doubt on the validity of subgenera, the observed relationships are concordant with biogeographic boundaries across the tropical range of Penaeus. Both the western Atlantic and eastern Pacific contain monophyletic species pairs which cluster together in all analyses. The Indo-Pacific contains a putative basal taxa (P. indicus), the deepest mtDNA lineages, and the highest diversity, including representatives of all three primary lineages observed in Penaeus. These data are consistent with the suggestion by Dall et al. (1990) that Penaeus arose in the Indo-Pacific and radiated eastward and westward to account for the current circumtropical distribution of the genus. This phylogenetic framework for Penaeus will enhance the scientific foundations for wildlife resource management and breeding experiments (hybridization and related manipulations) designed to improve the commercial value of captive strains.

Animals↗
PubMed1998

Phylogeography of the West Indian manatee (Trichechus manatus): how many populations and how many taxa?

To resolve the population genetic structure and phylogeography of the West Indian manatee (Trichechus manatus), mitochondrial (mt) DNA control region sequences were compared among eight locations across the western Atlantic region. Fifteen haplotypes were identified among 86 individuals from Florida, Puerto Rico, the Dominican Republic, Mexico, Columbia, Venezuela, Guyana and Brazil. Despite the manatee's ability to move thousands of kilometers along continental margins, strong population separations between most locations were demonstrated with significant haplotype frequency shifts. These findings are consistent with tagging studies which indicate that stretches of open water and unsuitable coastal habitats constitute substantial barriers to gene flow and colonization. Low levels of genetic diversity within Florida and Brazilian samples might be explained by recent colonization into high latitudes or bottleneck effects. Three distinctive mtDNA lineages were observed in an intraspecific phylogeny of T. manatus, corresponding approximately to: (i) Florida and the West Indies; (ii) the Gulf of Mexico to the Caribbean rivers of South America; and (iii) the northeast Atlantic coast of South America. These lineages, which are not concordant with previous subspecies designations, are separated by sequence divergence estimates of d = 0.04-0.07, approximately the same level of divergence observed between T. manatus and the Amazonian manatee (T. inunguis, n = 16). Three individuals from Guyana, identified as T. manatus, had mtDNA haplotypes which are affiliated with the endemic Amazon form T. inunguis. The three primary T. manatus lineages and the T. inunguis lineage may represent relatively deep phylogeographic partitions which have been bridged recently due to changes in habitat availability (after the Wisconsin glacial period, 10 000 B P), natural colonization, and human-mediated transplantation.

Animals↗
PubMed1996

Testing models of female reproductive migratory behaviour and population structure in the Caribbean hawksbill turtle, Eretmochelys imbricata, with mtDNA sequences.

Information on the reproductive behaviour and population structure of female hawksbill turtles, Eretmochelys imbricata, is necessary to define conservation priorities for this highly endangered species. Two hypotheses to explain female nest site choice, natal homing and social facilitation, were tested by analyzing mtDNA control region sequences of 103 individuals from seven nesting colonies in the Caribbean and western Atlantic. Under the social facilitation model, newly mature females follow older females to a nesting location, and subsequently use this site for future nesting. This model generates an expectation that female lineages will be homogenized among regional nesting colonies. Contrary to expectations of the social facilitation model, mtDNA lineages were highly structured among western Atlantic nesting colonies. These analyses identified at least 6 female breeding stocks in the Caribbean and western Atlantic and support a natal homing model for recruitment of breeding females. Reproductive populations are effectively isolated over ecological time scales, and recovery plans for this species should include protection at the level of individual nesting colonies.

Animals↗
PubMed1996

Phylogeography and population structure of the Atlantic and Mediterranean green turtle Chelonia mydas: a mitochondrial DNA control region sequence assessment.

Mitochondrial (mt) DNA sequences were analysed to resolve the phylogeography and population genetic structure of Atlantic and Mediterranean populations of green turtles (Chelonia mydas). Analysis of sequence variation over 487 base pairs of the control (D-loop) region identified 18 haplotypes among 147 individuals from nine nesting populations. Pairwise comparisons of haplotype frequencies distinguished most nesting colonies, indicating significant genetic differentiation among rookeries and a strong propensity for natal homing behaviour by nesting females. Comparison of control region sequence data to earlier restriction fragment length polymorphism (RFLP) data for the same individuals demonstrates approximately a sixfold higher substitution rate in the 5' end of the control region. The sequence data provide higher resolution both in terms of the number of mtDNA genotype variants and the phylogeographic relationships detected within the Atlantic region, and reveal a gene genealogy that distinguishes two groups of haplotypes corresponding to (i) the western Caribbean and Mediterranean, and (ii) eastern Caribbean, South Atlantic and West Africa. The data suggest that phylogeographic patterns in the Atlantic Ocean may be interpreted in terms of female nest site fidelity and episodic dispersal events. The distribution of mtDNA haplotypes within the region is thus explained by the geological and climatic alternations (glacial and interglacial) over the last million years.

Animals↗
PubMed1995

Trans-Pacific migrations of the loggerhead turtle (Caretta caretta) demonstrated with mitochondrial DNA markers.

Juvenile loggerhead turtles (Caretta caretta) have recently been documented in the vicinity of Baja California and thousands of these animals have been captured in oceanic fisheries of the North Pacific. The presence of loggerhead turtles in the central and eastern North Pacific is a prominent enigma in marine turtle distribution because the nearest documented nesting concentrations for this species are in Australia and Japan, over 10,000 km from Baja California. To determine the origin of the Baja California feeding aggregate and North Pacific fishery mortalities, samples from nesting areas and pelagic feeding aggregates were compared with genetic markers derived from mtDNA control region sequences. Overall, 57 of 60 pelagic samples (95%) match haplotypes seen only in Japanese nesting areas, implicating Japan as the primary source of turtles in the North Pacific Current and around Baja California. Australian nesting colonies may contribute the remaining 5% of these pelagic feeding aggregates. Juvenile loggerhead turtles apparently traverse the entire Pacific Ocean, approximately one-third of the planet, in the course of developmental migrations, but mortality in high-seas fisheries raises concern over the future of this migratory population.

Animals↗
PubMed1994

Evolutionary implications of the family of 14-3-3 brain protein homologs in Arabidopsis thaliana.

The GF14 family of proteins in Arabidopsis thaliana consists of a homologous group of polypeptides ranging in size from approximately 27 kDa to approximately 32 kDa. As a group, GF14 proteins are also homologous to a family of mammalian proteins most commonly referred to as 14-3-3 proteins. Several distinct and different biochemical activities have been historically attributed to the various isoforms of the mammalian 14-3-3 proteins. These data present the possibility that the various activities are performed by functionally distinct lineages of the gene family. Here we present phylogenetic analyses based on the derived amino acid sequences of five GF14 isoforms expressed in Arabidopsis suspension-cultured cells. A high degree of sequence integrity is apparent in the various Arabidopsis isoforms, and the overall structures of the plant forms are quite conserved with regard to the structures of the known mammalian forms. These gene phylogenies indicate no evolutionary conservation of specific isoform lineages within both plants and animals. Rather, the evolutionary history of this protein appears to be characterized by a separate radiation of plant and animal forms from a common ancestral sequence. Even though the plant and animal forms have evolved independently since that ancestral split, large domains are conserved in both major lineages.

14-3-3 Proteins↗