Primitive Species Research Articles

What Can Mechanisms Underlying Derived Traits Tell Us About the Evolution of Social Behavior?

AbstractSocial behavior, although rare, is a highly successful form of living that has reached its most extreme forms in eusocial insects. A tractable framework to understand social evolution is the study of major transitions in social behavior. This includes the transitions between solitary to social living, from species exhibiting intermediate degrees of sociality to species exhibiting true sociality, and from primitive to advanced eusocial species. The latter transition is characterized by the emergence of traits not previously found in primitive eusocial species, such as fixed morphological differences between castes and task specialization within the sterile caste. Such derived traits appear to exist in a binary fashion, present in advanced eusocial species, and absent or rare in primitive ones, and thus do not exist in a gradient that is easily tracked and compared between species. Thus, they may not be viewed as valuable to explore ultimate questions related to social evolution. Here, we argue that derived traits can provide useful insights on social evolution even if they are absent or rare in species with a lower social organization. This applies only if the mechanism underlying the trait, rather than the function it regulates for, can be traced back to the solitary ancestors. We discuss two examples of derived traits, morphological differences in female castes and primer pheromones regulating female reproduction, demonstrating how their underlying mechanisms can be used to understand major transitions in the evolution of social behavior and emphasize the importance of studying mechanistic, rather than functional continuity of traits.

Superoxide-anion triggers impairments of immune efficiency and stress response behaviors of Eisenia fetida earthworms

Superoxide-hydrogen peroxide (S-HP), triggered by Val16Ala-SOD2 human polymorphism, may influence the risk of depression. Therefore, it is plausible that higher basal S-anion levels and chronic inflammatory states associated with the VV-SOD2 genotype can negatively modulate the stress response associated with resilience in various species, from primitive species to humans. To test this hypothesis, Eisenia fetida earthworms were exposed for 24 h to 30 nM rotenone, which causes mitochondrial dysfunction by generating high S-anion levels (known as the “VV-like phenotype”), and 10 μM porphyrin, a SOD2-like compound, which generates elevated HP levels (known as the “AA-like phenotype”). The results suggested that both S-anion and HP acted as signaling molecules, differentially altering the immune function and acute hydric stressful response. Although the AA-like phenotype improved the immune and stress response efficiencies, the VV-like phenotype showed a downregulated expression of the toll-like receptor (EaTLR, JX898685) and antimicrobial peptide (AMP) (AF060552) genes, which triggered the impairment of encapsulation and earthworms extracellular trap (EET) processes used by earthworms to trap and destroy microorganisms. When exposed to adverse environments and dangerous hydric stress, VV-like earthworms exhibited an impulsive behavior and failed to quickly identify and migrate to a protected environment, unlike control earthworms and AA-like earthworms. All results corroborated that the S-anion imbalance could concomitantly induce alterations in immune function and stress behavior related to earthworm survival. From a human perspective, this information may corroborate the potential specific role of superoxide anion in the modulation of the stress response, resilience, and risk of depression.

Composition of the collection of primitive cultivated species within the Solanum L. section Petota Dumort. and contemporary trends in their research

The diversity of potato genetic resources in the VIR genebank harbors one of the world’s first collections of primitive cultivated species. These accessions are native potato varieties cultivated by the indigenous population of South America. The oldest accessions in the collection are traced back to 1927. Approximately one fifth of the collection (106 accessions out of 573) is the unique material procured by VIR’s collecting missions to Bolivia, Colombia, Ecuador, and Peru. According to S. Bukasov’s potato classification, the diversity of South American highland potatoes explored by VIR’s collectors belongs to spp. Solanum ajanhuiri Juz. et Buk., S. × chaucha Juz. et Buk., S. mammilliferum Juz. et Buk., S. phureja Juz. et Buk., S. rybinii Juz. et Buk., S. goniocalyx Juz. et Buk., S. stenotomum Juz. et Buk., S. tenuifilamentum Juz. et Buk., S.× juzepczukii Buk., and S. × curtilobum Juz. et Buk. Within this group of species, S. × ajanhuiri, S. phureja and S. stenostomum are the closest in their characteristics to ancient domesticated forms of tuber-bearing Solanum spp. This publication is an analytical review of the current composition of the primitive cultivated potato species collection and the results of its earlier studies. Ecogeographic descriptions of the sites native for cultivated potatoes and information on the sources of the accessions are presented. A large-scale evaluation of primitive cultivated potato accessions by a set of characters, carried out in field and laboratory experiments, uncovers their breeding potential and serves as the primary information platform for further indepth research. Studying S. phureja and closely related cultivated potato species is important for finding solutions of fundamental problems in plant biology. The data arrays accumulated today would facilitate targeted selection among accessions to identify most promising ones for molecular genetic studies into the gene pool diversity of potato species.

Textual research on origin and efficacy of Tibetan medicine "Shengdeng"

"Shengdeng" is a traditional Tibetan medicine, which has many synonyms. It is complex in origin and serious in mi-xing. In order to clarify the origin of "Shengdeng" and its medicinal use, this paper makes a textual research on the name, variety and efficacy of "Shengdeng" by consulting Tibetan medicine classics such as The Four Medical Trantras and Jingzhu Materia Medica, combined with modern literature of Tibetan medicine. It is clear that the synonyms, primitive species, mainstream varieties and functions of Tibetan medicine "Shengdeng". The collation and analysis of the literature shows that "Shengdeng" has effects of treating rheumatism, drying "Huangshui", detumescence and relieving pain, and is mainly used for the treatment of rheumatoid arthritis in Tibetan medicine. Its original varieties include 14 species of plants belonging to 6 families: Spicaceae, Rhamnaceae, Cephalotaxus, Leguminosae, Hematoxylaceae and Taxaceae. Combined with the collection of legal standards at all levels, the distribution of resources and the application of clinical prescriptions, it is considered that the mainstream species of "Shengdeng" are Rhamnella gilgitica, Xanthoceras sorbifolia, Rhamnus parvifolia. As a substitute, Acacia catechu is also widely used in clinic. The literature review and variety textual research on Tibetan medicine "Shengdeng" is helpful to improve the safety, effectiveness and quality controllability of its clinical application, and provide scientific basis for its further standard setting, pharmacodynamics research, new drug development and so on.

First discovery of fossil Episiphneus (Myospalacinae, Rodentia) from Northeast China

The first Episiphneus (Myospalacinae, Rodentia, Mammalia) fossils of the Late Pliocene from Northeast China are described here as E. dalianensis sp. nov., which were collected from the lowermost fossiliferous deposits from Jinyuan Cave of Luotuo Hill in Dalian, Liaoning Province. The new fossils include intact skull, mandibles and molars with roots. The skull is characterized by a flat occiput and the supra-occipital process cohering with the lambdoid crest; meanwhile distinctive dental features include rooted molars and anterior cap of m1 coated with enamel. The new species is morphologically distinct from those of the tribe Prosiphneini with convex occiput, as well as species of the tribe Mesosiphneini with occipital concavity; and should be referred to the genus Episiphneus of the trible Myospalacini. Episiphneus was previously represented by a single species, E. youngi, whose geographical distribution is restricted to North China during the Early Pleistocene, such as Zhoukoudian Locality18 (ZKD Loc.18), Beijing. The Jinyuan specimens are similar to E. youngi in cranial dome of both species bear flat occiput without interparietal, rooted hypsodont molars, and appreciably reduced M3/m3. Nonetheless, there are also differences in morphology between the new species and E. youngi, the type species of Episiphneus. For example, E. dalianensis sp. nov. is slightly smaller in size, with incisive foramen surrounded by premaxilla, and a well-developed 1st lingual reentrant angle (LRA1) on the M1. With relatively smaller size, rooted molars, thick enamel and developed enamel lakes formed by the reentrants, E. dalianensis sp. nov. is apparently more basal to Myospalax prosilurus and Myospalax psilurus. All the three species have the incisive foramen surrounded by premaxilla, the evident 1st lingual reentrant angle (LRA1) on the M1, obviously reduced M3/m3, and overlapping geographical distribution, suggesting that E. dalianensis sp. nov. represents a putative ancestor of the two others. As the first discovery of fossil Episiphneus from Northeast China, E. dalianensis sp. nov. is also the earliest and most primitive species of the genus. Its discovery has significant implications for reconstructing the origin, evolution and dispersal pattern of Myospalacinae in Northern China, as well as for discussing its palaeoecological variation.

Effects of several production methods on technological, textural and sensorial properties of emmer (Triticum turgidum ssp. dicoccum) bulgur.

In recent years, the interest in primitive wheat species including emmer (Triticum turgidum ssp. dicoccum) wheat and their characteristics have increased due to natural food trends. Bulgur is a nutritious and healthy product with long shelf life, produced from hard wheat species without the need for any additives. The basis of this study was to reveal the potential for bulgur production by the six production methods, combinations of three cooking (traditional, autoclave, microwave) and two drying (hot-air, microwave) methods of emmer wheat. In addition to some physical, chemical and technological properties of emmer wheat, yield, color, cooking time and textural and sensorial properties of the bulgur samples were investigated and statistically significant differences (p < 0.05) were recorded among the bulgur samples. Autoclave cooking had a negative effect on color and got the lowest sensorial acceptability scores. Microwave drying increased fine bulgur formation and shortened the cooking time. The volume and weight increase indexes were increased more than hot-air drying thanks to physical effects of microwave drying on the structure. According to the texture analysis results, microwave cooking increased the adhesivity, and microwave drying increased hardness and springiness. In conclusion, emmer wheat have great potential for bulgur production, and traditional cooked + hot air dried samples had better bulgur properties in overall.

A new hypercarnivorous mustelid (Mammalia, Carnivora, Mustelidae) from Batallones, late Miocene (MN10), Torrejón de Velasco, Madrid, Spain

We describe dentognathic remains of four individuals of the poorly known mustelid CircamustelaPetter, 1967 from the late Miocene sites of Batallones-3 and 5 (MN10, Torrejon de Velasco, Madrid, Spain). These new fossils allow us to describe Circamustela peignei n. sp., a more primitive species than Circamustela dechaseauxiPetter, 1967 from Can Llobateres (MN9, Vallès Penedès Basin, Spain). Circamustela peignei n. sp. shows, among other features, an M1 with a more developed metacone, a smaller metastylar area, a mesially located protocone, and a more developed m1 metaconid compared to that of C. dechaseauxi. The new taxon differs from most Euroasian Miocene marten-like mustelids, such as the middle Miocene martens “Martes” sansaniensis (Lartet, 1851), and “Martes” filholiDepéret, 1887, the vallesian Martes melibullaPetter, 1963 and the Turolian/Ventian Martes woodwardiPilgrim, 1931, Martes ginsburgi Montoya, Morales & Abella, 2011, Pekania palaeosinensis (Zdansky, 1924), and Paramartes pocockiKretzoi, 1952, in smaller size, a reduced lingual platform of the M1 and a more reduced m1 talonid and m2. However, C. peignei n. sp. is closer to the Chinese and Greek hypercarnivorous Sinictis dolichognathusZdansky, 1924. Circamustela spp., and SinictisZdansky, 1924 can be interpreted as adapted to a more carnivorous diet than those of the more generalist martens, such as Martes spp., ParamartesKretzoi, 1952 and Pekania spp.

Specialization of mucosal immunoglobulins in pathogen control and microbiota homeostasis occurred early in vertebrate evolution.

Although mammalian secretory immunoglobulin A (sIgA) targets mucosal pathogens for elimination, its interaction with the microbiota also enables commensal colonization and homeostasis. This paradoxical requirement in the control of pathogens versus microbiota raised the question of whether mucosal (secretory) Igs (sIgs) evolved primarily to protect mucosal surfaces from pathogens or to maintain microbiome homeostasis. To address this central question, we used a primitive vertebrate species (rainbow trout) in which we temporarily depleted its mucosal Ig (sIgT). Fish devoid of sIgT became highly susceptible to a mucosal parasite and failed to develop compensatory IgM responses against it. IgT depletion also induced a profound dysbiosis marked by the loss of sIgT-coated beneficial taxa, expansion of pathobionts, tissue damage, and inflammation. Restitution of sIgT levels in IgT-depleted fish led to a reversal of microbial translocation and tissue damage, as well as to restoration of microbiome homeostasis. Our findings indicate that specialization of sIgs in pathogen and microbiota control occurred concurrently early in evolution, thus revealing primordially conserved principles under which primitive and modern sIgs operate in the control of microbes at mucosal surfaces.

A New Species of Nyanzachoerus (Mammalia, Artiodactyla, Suidae, Tetraconodontinae) from the Upper Miocene Nakali Formation, Kenya

A new species of Nyanzachoerus (Mammalia, Artiodactyla, Suidae, Tetraconodontinae), Nyanzachoerus nakaliensis, is described on the basis of gnathodental specimens from the basal upper Miocene Nakali Formation (ca. 10 Ma) of central Kenya. Ny. nakaliensis is characterized by a lower crown height and relatively weaker furrows of the molars and proportionally larger P3–P4 compared to M3 among the species of the genus. It is the oldest and morphologically most primitive species of the genus. It shows close morphological similarities of the dentition with the Pliocene Asian tetraconodontine genus Sivachoerus, implying a possible closer phyletic relationship of Sivachoerus prior with Ny. nakaliensis rather than with Nyanzachoerus tulotos or Nyanzachoerus devauxi. This phyletic relationship implies a possibility that S. prior diverged from a stock of Ny. nakaliensis during the early late Miocene (Tortonian) in East Africa and then the lineage moved from East Africa to Asia. Finally, it should be stressed that there seems to be a problem of the paraphyly of the genus Nyanzachoerus.

Regulation of 14-3-3β/α gene expression in response to salinity, thermal, and bacterial stresses in Siberian sturgeon (Acipenser baeri).

The 14-3-3 proteins are a family of widely expressed acidic proteins, which are involved in the regulation of many biological processes of animals. However, no research regarding 14-3-3 has been described in sturgeon to date, one of the most primitive Actinopterygii species. Here, we identified the first 14-3-3 gene from Siberian sturgeon (Acipenser baeri), named Ab14-3-3β/α (GenBank Accession No. KY094076.1). The cDNA of Ab14-3-3β/α is 1212bp in length, containing a 5'-untranslated region (UTR) of 82bp, a 3'UTR of 392bp, and an open reading frame (ORF) of 738bp, encoding a polypeptide of 245 amino acids which contains a 14-3-3 homologs domain (PF00244). Phylogenetic analysis showed that the 14-3-3 gene product from Acipenser baeri is a counterpart of vertebrate 14-3-3β/α. The deduced Ab14-3-3β/α protein shares high identities of 46.5-95.5% with the homologs of other species. Ab14-3-3β/α mRNA was constitutively expressed in all examined tissues, with high expression levels in the blood and gill. Furthermore, the expression level of Ab14-3-3β/α mRNA increased significantly in the gill at 1h under acute salinity shock by transfer of Siberian sturgeons from fresh water (FW) to 15ppt. In fish subjected to a high temperature (31°C), Ab14-3-3β/α showed a significant upregulation in the liver at 3h compared with the control group (24°C). A 4.85-fold increase of Ab14-3-3β/α expression in the spleen of Siberian sturgeon was observed at 24h following Aeromonas hydrophila challenge. Collectively, these results indicated that Ab14-3-3β/α might play a certain role in sturgeon in response to some environmental stresses and bacterial challenge.

Eye location, cranial asymmetry, and swimming behavior of different variants of Solea senegalensis

Many flatfish species, such as Scophthalmus maximus, Paralichthys olivaceus, Solea senegalensis, are extensively cultured worldwide. In flatfishes, eye migration varies among different species and even within the same species. The genetic mechanism underlying eye migration is still unclear, and it is the key to improve metamorphosis in flatfish aquaculture and understand flatfish evolution. In this study, the high frequency of eye location variants in an artificial S. senegalensis population allowed us to investigate the eye preference during migration; completeness of the eye migration; and other related left-right asymmetric characteristics, such as asymmetrical skull remodeling and lying down on one side. The different frequencies of eye preference during migration, completeness of the eye migration, and settling side suggest that they are determined by different genotypes and imply independent evolutionary events during flatfish evolution. We found that the swimming time may be related to the completeness of eye migration, and further the migration of the eye, the more time the fish spent at the sea bottom. The left-right asymmetric degrees of not only the frontal bones and lateral ethmoids but also the jaw bone, including the premaxillary, maxillary, and dentary bones, depend on the completeness of eye migration. Finally, we proposed a hypothesis for the asymmetric origin of flatfish that provides reasonable explanations for the selective advantages of primitive flatfish species.

Anatomic and Morphological Peculiarities of Fruits and Seeds of Sorbus L. (Rosaceae) Genus under Conditions of Introduction

The paper studies the anatomic and morphological peculiarities of fruits and seeds of 17 species of Sorbus introduced in the Saint Petersburg Botanical Garden, including one species of local flora, S. aucuparia L. f. rosea. The fruits and seed of Sorbus species are diverse, which can be used as taxonomy criteria in discussion of arguable issues arising during the systematization of the plant genus. The species differ in the external color of a fruit and morphology of seeds in them which can be dissimilar within one fruit or even one dissepiment. Seeds differ the most by shape and dimensions, structure and number of cell layers in the testa. In primitive and archaic species, the number of cell layers in the testa, especially parenchyma layers, is large (6–7 layers in S. cashmiriana and S. roopiana). The smallest number of parenchyma layers (2–4) is typical for more evolutionary advanced species S. sambucifolia, S. ‘Joseph Rock’, S. alnifolia, S. commixta and S. luristanica.

Effects of different cooking and drying methods on phenolic acids, carotenoids, and antioxidant activity of emmer (Triticum turgidum ssp. dicoccum) bulgur

AbstractBackground and objectivesEmmer (Triticum turgidum ssp. dicoccum) is an ancient hulled wheat with a high amount of nutrient and bioactive compounds. This study was aimed to investigate the changes in bioactive compounds and antioxidant activities of the emmer bulgurs produced by combinations of three cooking (traditional, autoclave, and microwave) and two drying (hot air and microwave) methods. The total polyphenol, carotenoid, antioxidant activity (DPPH radical scavenging activity and ferric reducing antioxidant power), and soluble‐free (SF), soluble‐conjugated (SC) and insoluble‐bound (IB) phenolic acid contents were determined.FindingsBioactive compounds and antioxidant activity decreased significantly in all bulgur production methods compared to emmer wheat. SF and SC phenolic acids of the bulgur samples decreased much more than IB phenolic acids, due to the better thermal stability of IB fraction. While microwave cooking was found to have a positive effect, microwave drying had a negative effect on preserving natural bioactive compounds.ConclusionsThe bulgur preparation method that most preserved the bioactive compounds was microwave cooking + hot air drying, followed by autoclave cooking + hot air.Significance and noveltyAs a primitive species, emmer is a valuable raw material with a growing interest in its properties and products. This is the first study aimed to compare the effects of several production methods on the bioactive compounds and antioxidant activity of emmer bulgur.

The lower–middle Viséan boundary interval in the Palaeotethys: refinements for the foraminiferal zonal schemes

AbstractA new foraminiferal subzone (Cf5α or MFZ12α) in between the classical foraminiferal zonal biozones is characterized by the first occurrence ofArchaediscusat concavus stage, primitive species ofPojarkovella, as well as the firstEndothyranopsiss.s. This interval is represented in England, France and Morocco (in the western Palaeotethys) and in South China, and more widely in Iran (in the eastern Palaeotethys), where it is partly similar to the MFZ11B subzone defined by previous authors. The position of this new biozone within the Livian or Holkerian substages suggests that it has to be considered as part of the middle Viséan substage. We therefore propose the abandonment of the notation MFZ11B, which includes lower Viséan rocks, and the subdivision of the middle Viséan zones MFZ12 and Cf5 into two subzones MFZ12α or Cf5α, and MFZ12β or Cf5β, with the latter subzone containing the classical Livian–Holkerian foraminiferal guidesPojarkovella nibelis and Koskinotextularia. Furthermore, the lower Viséan MFZ11 zone can be subdivided in most Palaeotethyan basins into three subzones: a lower MFZ11α subzone (characterized by the first occurrence ofUralodiscus rotundus, as well as most species ofGlomodiscus); a middle MFZ11β subzone (characterized by the first occurrence ofArchaediscusat involutus stage andConilidiscus); and an upper MFZ11γ subzone (characterized by the first occurrence ofNodosarchaediscus,Consobrinellopsis and Lituotubella).

Leveillula lactucae-serriolae on Lactuca serriola in Jordan

Jordan contributes significantly to the Near East plant biodiversity with numerous primitive forms and species of crops and their wild relatives. Prickly lettuce (Lactuca serriola) is a common species in Jordan, where it grows in various habitats. During a survey of wild Lactuca distribution in Jordan in August 2007, plants of L. serriola with natural infections of powdery mildew were observed at a site near Shobak (Ma’an Governorate). Lactuca serriola leaf samples with powdery mildew infections were collected from two plants and the pathogen was analyzed morphologically. Characteristics of the asexual and sexual forms were obtained. Sequence analyses of the rDNA ITS region and D1/D2 domains of the 28S rDNA were used to obtain phylogenetic data, and to reach taxonomic conclusions about these specimens. Molecular determination, performed by sequencing of the ITS region, proved its identity with the type material of Leveillula lactucae-serriolae. Sequencing of the 28S rDNA region provided the first verified GenBank record of Leveillula lactucae-serriolae deposited in this public nucleotide repository. This is the first taxonomically verified record of L. lactucae-serriolae on L. serriola growing wild in Jordan, and one of the first records of the fungus in the Near East.

Do Bumble Bees Produce Brood Pheromones?

Reproductive division of labor, a defining feature of social insects, is often regulated by a combination of behavioral and chemical means. It is hypothesized that behavioral interactions play a more important role in regulating reproduction of primitive eusocial species, while pheromones are typically used by large sized, advanced eusocial species. Here we examined if worker reproduction in the primitively eusocial species Bombus impatiens is regulated by brood pheromones. We recently demonstrated that worker egg laying in this species is inhibited by young larvae and triggered by pupae. However, the mechanism by which the brood communicates its presence and whether brood or hunger pheromones are involved remain unknown. We found that workers were behaviorally attracted to pupae over larvae or control in a choice experiment, in line with their reproductive interests. However, odors from larvae or pupae were insufficient to inhibit worker reproduction. We further show that the youngest larvae are particularly vulnerable to starvation, however, despite a slight attraction and fewer eggs laid by workers in the presence of starved compared withfed larvae, these effects were insignificant. Our study demonstrates that workers can differentiate between larvae and pupae, but not between starved and fed larvae based on olfactory information. However, these signals alone do not explain the reduction in worker egg laying previously found. Bumble bee workers may use information from multiple sources or rely solely on behavioral interactions with brood and other females to make decisions about reproduction, in line with their small colony size and simple social organization.

Reappraisal of some species of the giant galericine Deinogalerix (Mammalia, Eulipotyphla, Erinaceomorpha, Erinaceidae) from the Miocene of south-eastern Italy, with a review of the genus

A revision of the remains of Deinogalerix from the Terre Rosse of Gargano, stored at the Department of Earth Sciences of Florence, improved our knowledge of the genus. The goals of this study are to clear the taxonomic status of the specimens and to tackle several issues connected with the evolutionary relationships of the different species. The sample of dental remains of Deinogalerix freudenthali provides new information, which confirms that this species belongs to the most primitive members of the genus, alongside D. masinii. It is now clear that D. freudenthali is very close to the hypothetical ancestor of all other Gargano species, except D. masinii. Nonetheless, the oldest fissures of the Gargano Terre Rosse contain also primitive species of unsettled taxonomic and phylogenetic position. The present analysis shows the systematic validity of D. minor and D. intermedius, whose status was debated. Moreover, the study verifies the consistency of the two phyletic lineages Deinogalerix minor–D. brevirostris and Deinogalerix intermedius–D. koenigswaldi, as well as the co-occurrence of members of the two lines at least in the most recent Terre Rosse fissures. The enhanced information contributes to our understanding of the genus Deinogalerix and especially of the most ancient phases of colonisation of the Apulia Platform. Nonetheless, the fossil record of the genus remains imperfect, with many gaps blurring the origins of its various evolutionary lines.

A New Fossil Erinaceidae from the Shajingyi Area in the Lanzhou Basin, China

Here, we describe a new primitive Erinaceidae species, Oligoechinus lanzhouensis n. gen. n. sp., based on a specimen from late Oligocene strata of the Lanzhou Basin, Gansu Province. Its characteristics are as follows: the M1 width is longer than the length, the metastyle extends far disto‐labially, the posterior margin has strong curve and a distinct metaconule that is connected to the protocone by a postprotocrista is located in the centre of the tooth. The posterior arm of the metaconule is poorly developed. In the P4, the pterion of the metastyle is less developed and the metacone is carinate. In addition, O. lanzhouensis has a premolar larger than the canine tooth (P2 &gt; C) and P3 had no molarisation, characters also possessed by Erinaceus. Overall, O. lanzhouensis was similar to Mioechinus based on architectural tooth features, demonstrating a closed genetic relationship. Fossil Erinaceidae are relatively rare before the Miocene. The discovery of O. lanzhouensis provides an important insight into the origin of Mioechinus in China and the early evolution of the Erinaceidae. Our analysis shows that a relatively recent ancestor of Mioechinus had probably existed in the early Oligocene and that O. Lanzhouensis was likely an ancestral type of Mioechinus gobiensis, and its systematic position should be located at a transitional position between Amphechinus and Mioechinus.

Subfunctionalization and evolution of liver-expressed antimicrobial peptide 2 (LEAP2) isoform genes in Siberian sturgeon (Acipenser baerii), a primitive chondrostean fish species

Two liver-expressed antimicrobial peptide 2 (LEAP2) isoforms were characterized in a primitive chondrostean sturgeon species, Acipenser baerii (Acipenseriformes). A. baerii LEAP2 isoforms represented essentially common structures shared by their vertebrate orthologs at both genomic (i.e., tripartite organization) and peptide (two conserved disulfide bonds) levels. A. baerii LEAP2 isoforms (designed LEAP2AB and LEAP2C, respectively) phylogenetically occupy the most basal position in the actinopterygian lineage and represent an intermediate character between teleostean and tetrapodian LEAP2s in the sequence alignment. Molecular phylogenetic analysis including LEAP2s from extant primitive fish species indicated that the evolutionary origin of ancestral LEAP2 in vertebrate groups should date back to earlier than the actinopterygian-sarcopterygian split. Gene expression assays under both basal and stimulated conditions suggested that A. baerii LEAP2 isoforms have undergone substantial subfunctionalization in tissue distribution pattern, developmental/ontogenetic expression, and immune responses. LEAP2AB showed a predominant liver expression, while LEAP2C exhibited the highest level of expression in the intestine. LEAP2C was a more dominantly expressed isoform during embryonic development and prelarval ontogeny. The LEAP2AB isoform is more closely associated with innate immune response to microbial invasion, compared with LEAP2C, as evidenced by results from LPS, poly(I:C) and Aeromonas hydrophila challenges. Synthetic mature peptides of LEAP2AB displayed a more potent antimicrobial activity than did LEAP2C. Data from this study could be useful not only to provide deeper insights into the evolutionary mechanism of LEAP2 in the actinopterygian lineage but also to better understand the innate immunity of this commercially important chondrostean species.

Partial and full root-zone drought stresses account for differentiate root-sourced signal and yield formation in primitive wheat

BackgroundPartial and full root-zone drought stresses are two widely used methods to induce soil drying in plant container-culture experiments. Two methods might lead to different observational results in plant water relation, such as non-hydraulic root-sourced signal (nHRS). We compared partial and full stress methods to induce nHRS in two diploids (MO1 and MO4) and two tetraploids (DM 22 and DM 31) wheat varieties under pot-culture conditions. Partial root-zone stress (PS) was performed using split-root alternative water supply method (one half wetting and the other drying) to induce the continuous operation of nHRS, and full root-zone stress (FS) was exposed to whole soil block to induce periodic operation of nHRS since jointing stage.ResultsWe tested the two drought methods whether it influenced the nHRS mediated signalling and yield formation in primitive wheat species. Results showed that partial root-zone stress caused more increase in abscisic acid (ABA) production and decline in stomatal closure than full root-zone stress method. The incline in ABA was closely related to triggering reactive oxygen species (ROS) generation, and reducing cytokinin synthesis which, thereby, led to crosstalk with other signalling molecules. Furthermore, PS up-regulated the antioxidant defense system and proline content. Water use efficiency and harvest index was significantly increased in PS, suggesting that PS was more likely to simulate the occurrence of nHRS by increasing the adaptive strategies of plants and closer to natural status of soil drying than FS.ConclusionThese findings lead us to conclude that partial root-zone stress method is more feasible method to induce nHRS which has great capacity to reduce water consumption and enhance plant adaptation to constantly changing environment. These observations also suggest that different root-zone planting methods can be considered to improve the plant phenotypic plasticity and tolerance in water-limited rainfed environments.