Byssal proteins of the freshwater zebra mussel,Dreissena polymorpha

The freshwater zebra mussel (Dreissena polymorpha) is a notorious biofouling organism. It adheres to a variety of substrata underwater by means of a proteinaceous structure called the byssus, which consists of a number of threads with adhesive plaques at the tips. The byssal proteins are difficult to characterize due to extensive cross-linking of 3,4-dihydroxyphenylalanine (DOPA), which renders the mature structure largely resistant to protein extraction and immunolocalization. By inducing secretion of fresh threads and plaques in which cross-linking is minimized, three novel zebra mussel byssal proteins were identified following extraction and separation by gel electrophoresis. Peptide fragment fingerprinting was used to match tryptic digests of several gel bands against a cDNA library of genes expressed uniquely in the mussel foot, the organ which secretes the byssus. This allowed identification of a more complete sequence of Dpfp2 (D. polymorpha foot protein 2), a known DOPA-containing byssal protein, and a partial sequence of Dpfp5, a novel protein with several typical characteristics of mussel adhesive proteins.     

Towards a new classification of the giant paraphyletic genus Cyperus (Cyperaceae): phylogenetic relationships and generic delimitation in C4 Cyperus

Maximum likelihood and Bayesian inference analyses of nuclear ribosomal DNA (ETS1f) and plastid DNA (rpl32‐trnL, trnH‐psbA) sequence data are presented for ‘C₄ Cyperus’ (Cyperaceae). The term ‘C₄ Cyperus’ encompasses all species of Cyperus s.l. that use C₄ photosynthesis linked with chlorocyperoid vegetative anatomy. Sampling comprises 107 specimens of 104 different taxa, including many of the subdivisions of C₄ Cyperus s.s. and all C₄ segregate genera (Alinula, Ascolepis, Kyllinga, Lipocarpha, Pycreus, Queenslandiella, Remirea, Sphaerocyperus and Volkiella). According to our results, C₄ Cyperus is a well‐supported monophyletic clade nested in C₃ Cyperus. Despite the lack of resolution along the backbone of the C₄ Cyperus clade and for some internal branches, several well‐supported clades can be distinguished. The first clade in C₄ Cyperus is formed by Cyperus cuspidatus and C. waterloti. Other recognizable and well‐supported clades correspond to segregate genera, i.e. Ascolepis, Lipocarpha including Volkiella, and Kyllinga. Species of C₄ Cyperus s.s. form a core grade in which the C₄ segregate genera are embedded. Pycreus, the largest segregate genus composed of c. 120 species, is not monophyletic as it includes several C₄ species of Cyperus s.s. This study establishes a phylogenetic framework for revising the classification and character evolution in Cyperus s.l. © 2013 The Linnean Society of London     

A new Manjarivolo Paulian, 1974 (Coleoptera: Scarabaeidae: Aphodiinae: Aulonocnemini) and comments on the unusual morphology of the scutellum

Manjarivolo randrianirinai n. sp. is described from Southern Madagascar (Andohahela massif). Remarks on its ecology and morphology are added and a key to Manjarivolo species is provided as well as a complete photographic iconography of all known species. The scutellum of Aulonocnemini displays an unusual morphology, reported for the first time within Scarabaeoidea. For the first time we provide scanning electron microscope micrographs of the mouthparts of these beetles.     

Larva,pupa and adult male of Atopsyche (Atopsyche) maxi,a new species from northwestern Argentina and southern Bolivia (Trichoptera: Hydrobiosidae)

Rhagovelia pediformis sp. n. is described from western Colombia and placed in the R. elegans group.     

Le genre Cratopus aux îles Seychelles (Coleoptera : Curculionidae)

Les espèces seychelloises du genre Cratopus Schoenherr 1823 sont révisées, et quatre nouveaux taxons sont décrits. Espèce de grande taille (16–19 mm), C. roberti n. sp. possède dix stries élytrales, des fémurs antérieurs portant de petits denticules, y compris sur la dent, et un revêtement squamuleux vert métallique, avec une bande blanche le long de la base et des côtés des élytres, ainsi que sur les côtés du prothorax. Long de 8–10 mm, C. venustus n. sp. se reconnait à ses téguments noirs et brillants, sa vestiture réduite bleu-vert métallique, ses douze stries élytrales de forts points, ainsi qu’à ses interstries 8 et 9 caréniformes. C. griseovestitus northislandensis n. ssp. diffère de la forme nominative C. griseovestitus griseovestitus Linell 1887 par ses téguments coriacés et sa vestiture métallique du dessus dense, à reflets cuivre doré ou verts, et non gris blanchâtre ou bleuâtre. C. griseovestitus fregata n. ssp. diffère de son côté de la forme nominative par ses téguments bruns plus ou moins foncés, saupoudrés de poils et de squamules très petits. Les synonymies de C. parcesquamosus Fairmaire 1893 et de C. abbotti Linell 1907 avec C. aurostriatus Fairmaire 1892 sont confirmées, et enfin un tableau de détermination des espèces seychelloises du genre est donné. Les Cratopus des Seychelles se divisent en un ensemble de trois espèces du groupe de griseovestitus, à large répartition, habitant les côtes et les îles coralliennes basses et probablement d’arrivée récente, et un ensemble de six espèces limitées aux îles granitiques, où cinq d’entre elles ont une distribution limitée à l’intérieur d’une île ou deux. Elles sont certainement de souche beaucoup plus ancienne. Les Cratopus des Seychelles sont folivores à l’état adulte, et souvent polyphages. Une liste de leurs plantes-hôtes connues est donnée.     

Development of a highly-efficient CHO cell line generation system with engineered SV40E promoter

Chinese hamster ovary (CHO) cells have been one of the most widely used host cells for the manufacture of therapeutic recombinant proteins. An effective and efficient clinical cell line development process, which could quickly identify those rare, high-producing cell lines among a large population of low and non-productive cells, is of considerable interest to speed up biological drug development. In the glutamine synthetase (GS)-CHO expression system, selection of top-producing cell lines is based on controlling the balance between the expression level of GS and the concentration of its specific inhibitor, l-methionine sulfoximine (MSX). The combined amount of GS expressed from plasmids that have been introduced through transfection and the endogenous CHO GS gene determine the stringency and efficiency of selection. Previous studies have shown significant improvement in selection stringency by using GS-knockout CHO cells, which eliminate background GS expression from the endogenous GS gene in CHOK1SV cells. To further improve selection stringency, a series of weakened SV40E promoters have been generated and used to modulate plasmid-based GS expression with the intent of manipulating GS-CHO selection, finely adjusting the balance between GS expression and GS inhibitor (MSX) levels. The reduction of SV40E promoter activities have been confirmed by TaqMan RT-PCR and GFP expression profiling. Significant productivity improvements in both bulk culture and individual clonal cell line have been achieved with the combined use of GS-knockout CHOK1SV cells and weakened SV40E promoters driving GS expression in the current cell line generation process. The selection stringency was significantly increased, as indicated by the shift towards higher distribution of producing-cell populations, even with no MSX added into cell culture medium. The potential applications of weakened SV40E promoter and GS-knockout cells in development of targeted integration and transient CHO expression systems are also discussed.     

Molecular systematics of pinniped hookworms (Nematoda: Uncinaria): species delimitation,host associations and host-induced morphometric variation

Hookworms of the genus Uncinaria have been widely reported from juvenile pinnipeds, however investigations of their systematics has been limited, with only two species described, Uncinaria lucasi from northern fur seals (Callorhinus ursinus) and Uncinaria hamiltoni from South American sea lions (Otaria flavescens). Hookworms were sampled from these hosts and seven additional species including Steller sea lions (Eumetopias jubatus), California sea lions (Zalophus californianus), South American fur seals (Arctocephalus australis), Australian fur seals (Arctocephalus pusillus), New Zealand sea lions (Phocarctos hookeri), southern elephant seals (Mirounga leonina), and the Mediterranean monk seal (Monachus monachus). One hundred and thirteen individual hookworms, including an outgroup species, were sequenced for four genes representing two loci (nuclear ribosomal DNA and mitochondrial DNA). Phylogenetic analyses of these sequences recovered seven independent evolutionary lineages or species, including the described species and five undescribed species. The molecular evidence shows that U. lucasi parasitises both C. ursinus and E. jubatus, whereas U. hamiltoni parasitises O. flavescens and A. australis. The five undescribed hookworm species were each associated with single host species (Z. californianus, A. pusillus, P. hookeri, M. leonina and M. monachus). For parasites of otarids, patterns of Uncinaria host-sharing and phylogenetic relationships had a strong biogeographic component with separate clades of parasites from northern versus southern hemisphere hosts. Comparison of phylogenies for these hookworms and their hosts suggests that the association of U. lucasi with northern fur seals results from a host-switch from Steller sea lions. Morphometric data for U. lucasi shows marked host-associated size differences for both sexes, with U. lucasi individuals from E. jubatus significantly larger. This result suggests that adult growth of U. lucasi is reduced within the host species representing the more recent host–parasite association. Intraspecific host-induced size differences are inconsistent with the exclusive use of morphometrics to delimit and diagnose species of Uncinaria from pinnipeds.