Multiple γ-glutamylation: A novel type of post-translational modification in a diapausing Artemia cyst protein

A highly hydrophilic, glutamate-rich protein was identified in the aqueous phenol extract from the cytosolic fraction of brine shrimp (Artemia franciscana) diapausing cysts and termed Artemia phenol soluble protein (PSP). Mass spectrometric analysis revealed the presence of many protein peaks around m/z 11,000, separated by 129 atomic mass units; this value corresponds to that of glutamate, which is strongly suggestive of heterogeneous polyglutamylation. Polyglutamylation has long been known as the functionally important post-translational modification of tubulins, which carry poly(l-glutamic acid) chains of heterogeneous length branching off from the main chain at the γ-carboxy groups of a few specific glutamate residues. In Artemia PSP, however, Edman degradation of enzymatic peptides revealed that at least 13, and presumably 16, glutamate residues were modified by the attachment of a single l-glutamate, representing a hitherto undescribed type of post-translational modification: namely, multiple γ-glutamylation or the addition of a large number of glutamate residues along the polypeptide chain. Although biological significance of PSP and its modification is yet to be established, suppression of in vitro thermal aggregation of lactate dehydrogenase by glutamylated PSP was observed.     

A black-and-red stick insect from the Philippines – observations on the external anatomy and natural history of a new species of Orthomeria

A new stick insect of the genus Orthomeria Kirby, 1904 (Phasmatodea, Aschiphasmatidae) is described from the Philippines. Orthomeria (Orthomeria) kangi sp. n. is readily distinguished from all other congeners by the distinctive blood red colouration of the costal region of the hind wings. Major features of the external morphology of adults, eggs, and first-instar nymphs are illustrated. Locomotory attachment pads are of the smooth type with irregular microgrooves on the contact surface. An unusual condition of male terminalia is the absence of tergal thorn pads on segment 10. The male clasping organs are represented by an elongated vomer terminating in a prominent spine, and by incurved cerci featuring a bilobed apex equipped with a sharp blade-like ridge. Intraspecific variation in body colouration and hind wing length occurs in females. The new species lives at 400-650 m elevation in the surroundings of the Sablang and Tuba regions, in the Benguet Province of Luzon island. Host plants include Ficus spp. (Moraceae), and Pipturus spp. and Leucosyke spp. (Urticaceae). Observations on the mating and defensive behaviour are presented. Orthomeria (Orthomeria) catadromus (Westwood, 1859) is recognised as a junior synonym of Orthomeria (Orthomeria) pandora (Westwood, 1859), syn. n. A lectotype is designated for both species. Finally, an updated identification key to the species of the subgenus Orthomeria is provided.     

How is a giant sperm ejaculator formed? Development of the Zenker organ after the last moult in Pseudocandona marchica (Crustacea,Ostracoda, Candonidae)

‘Giant sperm’, in terms of exceptionally long spermatozoa, occur in various taxa in the animal kingdom, particularly in arthropods. In freshwater ostracods (Cypridoidea) reproducing with giant sperm, males are equipped with a pair of specialized ejaculators, or Zenker organs, located in the distal part of vas deferens.     

On the “cytosociology” of enzyme action in vivo: A novel thermodynamic correlate of biological evolution

The evolution of enzyme action in vivo is examined, in the light of established thermodynamic correlates of biological evolution. Adopting a “process” view of matter in the “living state,” the authors focus the analysis on the transition-state theory of reaction rates. Thus, the free-energy change associated with the transition-state barrier is seen as a primary target in the evolution of cellular metabolism. The utility and limitations of reductionistic approaches to enzyme evolution, based on the single enzyme, are explored first. Then, canvassing the wealth of evidence on the role of enzyme organization in vivo, the authors synthesize a “cytosociological” view of enzyme evolution. In this view, a composite (resultant) of individual transition-state barriers is deemed a more appropriate “potential function” for modification in the higher evolution of cell metabolism. The suggested direction of evolutionary changes in this function, dictated by the increasing “socialization” of enzyme action in vivo, stands as a novel postulate. This approach is shown to be completely consonant with current thinking on the thermodynamics of biological evolution, and to provide further insight into the nature of material transformations in the “living state”.     

A hypothesis about the origin of sperm storage in the Eubrachyura, the effects of seminal receptacle structure on mating strategies and the evolution of crab diversity: How did a race to be first become a race to be last?

The origins and evolution of sperm storage in Brachyura are enigmatic: sperm is either stored in seminal receptacles, accessible via the vulvae on the sixth thoracic sternite, or in spermathecae at the border between the seventh and eighth sternites. Crabs with spermathecae are collectively referred to as “podotremes” while crabs with seminal receptacles belong to the Eubrachyura. The position of gonopores is the primary basis for subdividing the Eurachyura into the Heterotremata (female vulvae + males with coxal gonopores) and Thoracotremata (female vulvae + males with sternal gonopores). We present a hypothesis about the evolution of seminal receptacles in eubrachyuran female crabs and argue that the sternal gonopore has been internalized into chitin-lined seminal receptacles and the vulva is in fact a secondary aperture. The loss of some or all of the ancestral chitinous seminal receptacle lining was linked to ventral migration of the oviduct connection. Male and female strategies are to maximize gamete fertilization. The most important variable for females is sperm supply, enhanced by long-term storage made possible by the seminal receptacle. To maximize their fertilization rates males must adapt to the structure of the seminal receptacle to ensure that their sperm are close to the oviduct entrance. The major evolutionary impetus for female mating strategies was derived from the consequences of better sperm conservation and the structure of the seminal receptacle. The advantages were all to the females because their promiscuity and sperm storage allowed them to produce more genetically variable offspring, thereby enhancing variation upon which natural selection could act. We extend our arguments to Brachyura as a whole and offer a unifying explanation of the evolution of seminal receptacles, comparing them with the spermathecae found in “Podotremata”: they were independent solutions to the same problem: maintaining sperm supply during evolutionary carcinization.Explanation of eubrachyuran mating strategies requires analysis of the mating–moulting link, indeterminate vs. determinate growth format and seminal receptacle structure. Two alternatives for each of these characters means that there are eight possible outcomes. Six of these outcomes have been realized, which we term Portunoid, Majoid, Eriphoid, Xanthoid, Cancroid, and Grapsoid–Ocypodoid strategies, respectively. Mapping these characters on to a workable phylogeny (wherein some changes to the seminal receptacle + moulting–mating links are assumed to have occurred more than once) produces the following relationships: Portunoids + Majoids are a sister group to the rest of the Eubrachyura, which fall into two sister groups, Eriphoids + Xanthoids and Cancroids + Grapsoid–Ocypodoids and the “Podotremata” is sister group to all the Eubrachyura. We conclude that what began as a race to be the first to mate was turned on its head to become a race to be last, by the evolutionary changes to the seminal receptacle. Eubrachyuran females were advantaged by greater reproductive autonomy, more opportunity to mate with other males, resulting in more genetically variable progeny and leading to the evolution of much greater taxonomic diversity compared to “podotremes”.     

Evidence for participation of GCS1 in fertilization of the starlet sea anemone Nematostella vectensis: Implication of a common mechanism of sperm–egg fusion in plants and animals

It has been reported that GCS1 (Generative Cell Specific 1) is a transmembrane protein that is exclusively expressed in sperm cells and is essential for gamete fusion in flowering plants. The GCS1 gene is present not only in angiosperms but also in unicellular organisms and animals, implying the occurrence of a common or ancestral mechanism of GCS1-mediated gamete fusion. In order to elucidate the common mechanism, we investigated the role of GCS1 in animal fertilization using a sea anemone (Cnidaria), Nematostella vectensis. Although the existence of the GCS1 gene in N. vectensis has been reported, the expression of GCS1 in sperm and the role of GCS1 in fertilization are not known. In this study, we showed that the GCS1 gene is expressed in the testis and that GCS1 protein exists in sperm by in situ hybridization and proteomic analysis, respectively. Then we made four peptide antibodies against the N-terminal extracellular region of NvGCS1. These antibodies specifically reacted to NvGCS1 among sperm proteins on the basis of Western analysis and potently inhibited fertilization in a concentration-dependent manner. These results indicate that sperm GCS1 plays a pivotal role in fertilization, most probably in sperm–egg fusion, in a starlet sea anemone, suggesting a common gamete-fusion mechanism shared by eukaryotic organisms.     

Short communication: Extraction of sp18 family membrane proteins on posterior head of bull sperm and the effect of anti‐sp18 IgG on sperm motility and murine in vitro fertilization

Abstract

Bovine sperm heads were separated via ultrasonic treatment and centrifugation. Anti‐bull sperm IgG was produced by immunizing rabbits with acrosome‐reacted bull sperm heads. SDS PAGE patterns revealed that the main membrane proteins on acrosome‐reacted bull sperm head were sp18 family, including 18, 16, and 14 kD, which represented about 64% of the total membrane proteins in bull sperm. Indirect immunofluorescence shown sp18 antigens primarily distributed in postacrosomal and proximal tail regions. Western blot analysis revealed that the anti‐bull sperm IgG reacted with sp18 antigens in acrosome‐reacted bull sperm head and bull seminal plasma. Anti‐bull sperm IgG also reacted with 14, 16, 18, 42, 57 and 60 kD proteins in fresh bull, mouse and rabbit sperm. Anti‐sp18 IgG caused agglutination of bull and rabbit sperm, but had no effect on murine sperm. In murine in vitro fertilization trials, preincubating capacitated sperm with 0.364 mg/ml of anti‐sp18 IgG resulted in a decrease in the fertilization rate from 75.6% in the controls to 50.8% in the experimental groups (p<0.001).     

Presence of Zanthopsis M’Coy, 1849 (Crustacea: Decapoda: Brachyura) in the Early Eocene of Iran,and comments on the different species and/or morphotypes and their palaeobiogeography

In the present work, we report the discovery of several carapaces of Zanthopsis sp. from the Lower Eocene of Central Iran, which represent the easternmost record of the genus. In addition, we discuss on the similarities of the different species and/or morphotypes of the genus, and conclude that the European species could be ascribed to the “Zanthopsis leachii complex”, until future works determine the validity of the species therein contained. In this sense, Zanthopsis jacobi Van Straelen, 1924, in agreement with Artal and Vía (1988), is herein considered a junior synonymous of Z. dufouri (H. Milne Edwards in d’Archiac, 1850). The presence of Zanthopsis in the lower Eocene of Iran suggests homogeneity of the brachyuran fauna on both sides of the Tethys Realm.     

Segmental duplication associated with the human-specific inversion of chromosome 18: a further example of the impact of segmental duplications on karyotype and genome evolution in primates

The human-specific pericentric inversion of chromosome 18 was analysed using breakpoint-spanning BACs from the chimpanzee and human genome. Sequence and FISH analyses disclosed that the breakpoints map to an inverted segmental duplication of 19-kb, which most likely mediated the inversion by intrachromosomal homologous recombination. The 19-kb duplication encompasses the 3 end of the ROCK1 gene and occurred in the human lineage. Only one copy of this segment is found in the chimpanzee. Due to the inversion, the genomic context of the ROCK1 and USP14 genes is altered. ROCK1 flanks USP14 in the long arm of the chimpanzee chromosome 17, which is homologous to human chromosome 18. This order is interrupted by the inversion in humans. ROCK1 is localized close to the pericentromeric region in 18q11 and USP14 is inverted to distal 18p11.3 in direct neighbourhood to LSAU-satellites, -satellites and telomere-associated repeats. Our findings essentially confirm the analysis of Dennehey et al. (2004). Intriguingly, USP14 is differentially expressed in human and chimpanzee cortex as well as fibroblast cell lines determined previously by the analysis of oligonucleotide arrays. Either position effects mediated by the proximity to the telomeric region or nucleotide divergence in regulatory regions might account for the differential expression of USP14. The assignment of the breakpoint region to a segmental duplication underlines the significance of the genomic architecture in the context of genome and karyotype evolution in hominoids.     

Experiments on the physiology of southern and northern krill,Euphausia superba and Meganyctiphanes norvegica,with emphasis on moult and growth – a review

Physiological data are needed for life history studies on krill, and as parameters for input into energy budgets and models. In conjunction with moult and growth data, these may also prove useful for assessing the fishable biomass of krill. Here, the development of physiological concepts in experimental krill research is briefly evaluated, with emphasis on the gaps to be filled. Krill growth is very flexible, as well as strongly temperature and nutrition dependent. The polar Antarctic krill Euphausia superba grows as fast as the boreal species Meganyctiphanes norvegica, at least during the first 2.5 years, and the species are comparable in terms of physiological plasticity. Accordingly, as krill appear to adjust quickly to specific laboratory conditions, short-term experiments are essential if field conditions are to be reflected as closely as possible. Furthermore, direct comparisons between laboratory experiments and swarming studies in the field are advantageous. For these, M. norvegica is particularly well-suited, as swarms can be followed over longer times and more easily than in E. superba. For example, processes of moult and reproduction were found to be highly coordinated in swarms and populations of Northern krill. For this species a conceptual model of reproduction was developed based on a combination of short-term laboratory observations coupled with field data on moult and ovary stages. In further physiological experiments krill should be studied as groups when swarming. Using proxies, that is applying physiological and/or biochemical methods side by side, is a promising way to enhance the reliability of life history data.     

Understanding reversals in the relative strength of sexual selection on males and females: a role for sperm competition?

Sperm competition affects sexual selection intensity on males, but models suggest it cannot affect the relative intensity of sexual selection on males compared to females. However, if sperm competition depresses the payoff for male multiple mating, it could affect the relative intensity of sexual selection and even cause sexual selection to be more intense on females than males (reversal of typical pattern). To evaluate how sperm competition, energy availability, and parental investment affect the intensity of sexual selection on each sex, I constructed a simulation model using the relationship between fecundity and number of mates to estimate sexual selection gradients. Unlike earlier models, I include a trade-off between paternal investment and sperm competition ability. The amount of energy available for reproduction affects the sexual selection gradient for each sex. Reversals in the sex experiencing stronger sexual selection do occur when additional paternal investment reduces a male's ability to compete for fertilizations within females. The shape of the distribution of mates for each sex (determined by mate competition) is also important. Output from the model is qualitatively similar to empirical data from insects with paternal investment. This model challenges previous thinking about the role of sperm competition in sex-role reversal.     

A novel point mutation in an acceptor splice site of intron 32 (IVS32 A–12→G) but no exon 3 mutations in the glycogen debranching enzyme gene in a homozygous patient with glycogen storage disease type IIIb

Genetic deficiency of the glycogen-debranching enzyme (debrancher) causes glycogen storage disease type III (GSD III), which is divided into two subtypes: IIIa and IIIb. In GSD IIIb, glycogen accumulates only in the liver, whereas both liver and muscles are involved in GSD IIIa. The molecular basis for the differences between the two subtypes has not been fully elucidated. Recently, mutations in exon 3 of the debrancher gene were reported to be specifically associated with GSD IIIb. However, we describe a homozygous GSD IIIb patient without mutations in exon 3. Analysis of the patient’s debrancher cDNA revealed an 11-bp insertion in the normal sequence. An A to G transition at position –12 upstream of the 3′ splice site of intron 32 (IVS 32 A^–12→G) was identified in the patient’s debrancher gene. No mutations were found in exon 3. Mutational analysis of the family showed the patient to be homozygous for this novel mutation as well as three polymorphic markers. Furthermore, the mother was heterozygous and the parents were first cousins. The acceptor splice site mutation created a new 3′ splice site and resulted in insertion of an 11-bp intron sequence between exon 32 and exon 33 in the patient’s debrancher mRNA. The predicted mutant enzyme was truncated by 112 amino acids as a result of premature termination. These findings suggested that a novel IVS 32 A^–12→G mutation caused GSD IIIb in this patient. Received: 1 August 1997 / Accepted: 22 September 1997     

Identification of a novel CCM2 gene mutation in an Italian family with multiple cerebral cavernous malformations and epilepsy: A causative mutation?

Cerebral cavernous malformations (CCMs; OMIM 116860) are vascular anomalies mostly located in the central nervous system (CNS) and occasionally within the skin and retina.     

Eolacertidae: a new extinct clade of lizards from the Palaeogene; with comments on the origin of the dominant European reptile group – Lacertidae

We describe a new lizard taxon, Stefanikia siderea gen. et sp. nov., from the early-middle Eocene locality of Messel in Germany based on a nearly complete skeleton, which we studied using μCT methods. It shares many characters with the Eocene taxon Eolacerta, which is broadly distributed in the Eocene of central and Western Europe, but is much smaller and shows several important anatomical differences. The new discovery sheds light on the paleodiversity of these lizards in the Eocene of Europe, and the new family name Eolacertidae is proposed to encompass Eolacerta and Stefanikia. The relationships of Eolacerta have been intractable. Our phylogenetic analyses confirm that Eolacertidae is a member of the clade Lacertiformes and provide strong support for a sister-group relationship to Lacertidae. In some places, skin impressions are preserved, displaying the body scalation. As such, the exquisitely preserved specimens of Eolacertidae from Messel provide new insight into the morphology and ecology of lizards on the stem of Lacertidae, Europe’s dominant group of living reptiles.

http://zoobank.org/urn:lsid:zoobank.org:pub:DFD01563-A913-4286-B64B-E0912474FD08     

Molecular modifications of MC31/CE9, a sperm surface molecule, during sperm capacitation and the acrosome reaction in the rat: is MC31/CE9 required for fertilization?

We examined the modification of the MC31 molecule during capacitation, the acrosome reaction, and studied its role in fertilization. These studies revealed that the molecular mass of MC31 in cauda spermatozoa was approximately 28,000-26,000 Dalton (28-26 kDa). A limited change in molecular mass was seen in capacitated spermatozoa. Treatment of sperm extracts with peptide-N-glycosidase (PN glycosidase) reduced the molecular mass of MC31 in both cauda and capacitated spermatozoa from 28-26 kDa to 23-20 kDa, suggesting that MC31 from both cauda and capacitated spermatozoa is glycosylated, and indicating that capacitation induces minor posttranslational modifications in the structure of the MC31 antigen. The MC31 antigen was redistributed from the midpiece of cauda epididymal spermatozoa to the head and equatorial segment after capacitation and acrosome reaction, respectively, when traced by indirect immunofluorescence under in vitro fertilization (IVF) conditions. Some spermatozoa did not stain for the MC31 antigen and might represent spermatozoa that have shed the antigen. IVF experiments conducted to assess the effect of an anti-MC31 monoclonal antibody (mMC31) revealed that this antibody significantly (P < 0.01) inhibited fertilization of cumulus-invested zona pellucida-intact and the zona pellucida-free oocytes in a dose-dependent manner. However, sperm-oolemma binding was not affected. These findings suggest the MC31 antigen facilitates sperm-oocyte interactions.     

A new genus and eight new species of the subtribe Anillina (Carabidae,Trechinae, Bembidiini) from Mexico,with a cladistic analysis and some notes on?the?evolution of the genus

One new genus and eight new species of anilline carabids are described from southern Mexico. The new genus, Zapotecanillus gen. n., is established for Z. oaxacanus (type species) sp. n., Z. nanus sp. n., Z. iviei sp. n., Z. ixtlanus sp. n., Z. montanus sp. n., and Z. kavanaughi sp. n. from the Sierra Madre de Oaxaca, Z. pecki sp. n. from the Sierra Madre del Sur, and Z. longinoi sp. n. from the Sierra Madre de Chiapas. A taxonomic key for all described species of Zapotecanillus and a cladistic analysis, based on morphological data, are provided. Morphological, behavioral and biogeographical aspects of the speciation in the genus obtained from the resulting cladogram are discussed.     

Inclusion complexation between baicalein and β-cyclodextrin and the influence of β-cyclodextrin on the binding of baicalein with DNA: a spectroscopic approach

This work deals with the commonly studied cyclic oligosaccharide and gains importance as it is entered on a drug delivering carbohydrate and provides insight into the oligosaccharide complex–biomolecular interaction. The binding of a flavone, baicalein, to β-cyclodextrin and calf thymus DNA is studied. The binding of baicalein to calf thymus DNA in the presence of β-cyclodextrin is analysed using the UV–vis absorption and fluorescence spectroscopy. The mode of binding and structure of the baicalein–β-cyclodextrin complex are reported. The role of the structure and the stoichiometry of the inclusion complex of baicalein–β-cyclodextrin in its influence on DNA binding are analysed.

Highlights

? This paper deals with the binding of a flavone, baicalein to β-cyclodextrin and/or DNA.

? The inclusion complexation between baicalein and β-cyclodextrin is analysed.

? The stoichiometry and the binding strength of the inclusion complex is reported.

? The role of β-cyclodextrin in tuning the binding of baicalein to DNA is emphasized.

? Spectroscopic and docking analysis are used to articulate the results.     

Larvicidal activity of spinosad and its impact on oviposition preferences of the West Nile vector Culex pipiens biotype molestus – A comparison with a chitin synthesis inhibitor

In the present study, the larvicidal activity of ageing aqueous suspensions of spinosad against larvae of Culex pipiens biotype molestus, as well as their effect on the oviposition preferences of adult gravid females were evaluated in laboratory bioassays. Spinosad was applied at its label dose and the aqueous stock suspensions were stored for various ageing intervals up to 38 days. Untreated distilled water and diflubenzuron served as negative and positive control, respectively. Stock suspensions were taken after 0, 2, 6, 8, 16, 30 and 38 days of storage for diflubenzuron and after 0, 2, 6, 8, 20 and 27 days for spinosad, and were used for the bioassays. Furthermore, the effect of spinosad on the oviposition response of Cx. p. biotype molestus gravid females was investigated in two-choice oviposition preference bioassays. Spinosad was evaluated at half of its label dose and at its label dose, whereas diflubenzuron and distilled water served as positive and negative control, respectively. Results showed that both insecticides were found highly effective for the control of Cx. p. biotype molestus larvae, for ageing intervals up to 27 and 38 days for spinosad and diflubenzuron, respectively. Spinosad acted immediately after the preparation of the insecticidal solution (LT₅₀ = 1.5 h), whereas for aged samples, LT₅₀ values increased with the increase of the ageing interval (LT₅₀ = 5 days for the 27 days old sample). For diflubenzuron, ageing time increased its insecticidal activity, as for aged diflubenzuron-treated solutions, lower LT₅₀ values were achieved. In the oviposition preference bioassays, significantly fewer egg rafts were laid in water treated with spinosad at its label dose compared to control. However, this was not the case for water treated with spinosad at half of its label dose. Oviposition Activity Index (OAI) values were always comprised between −0.3 and 0.3, showing no relevant oviposition deterrence or attraction. The results of the present study contribute to our understanding of the effect of ageing on insecticidal solutions widely used in urban areas to control Cx. p. biotype molestus. Although an important vector of high public health importance, Cx. p. biotype molestus has been scarcely studied as target of environmentally and toxicologically reduced risk insecticides, such as spinosad.     

A new species of Crinoniscus Pérez, 1900 (Crustacea: Isopoda: Crinoniscidae) parasitising the pedunculate barnacle Heteralepas newmani Buhl-Mortensen & Mifsud (Cirripedia: Heteralepadidae) with notes on its ecology and a review of the genus

Systematic Parasitology - The new species Crinoniscus stroembergi n. sp. belonging to the parasitic isopod family Crinoniscidae Bonnier, 1900, is described from a pedunculate barnacle host...