A new species of Pseudochalcura (Hymenoptera, Eucharitidae), with a review of antennal morphology from a phylogenetic perspective

Pseudochalcura alba Heraty & Heraty, sp. n. is described from Santiago del Estero and Catamarca provinces in northwestern Argentina. The male and female have long dorsal rami on all of the flagellomeres basal to the terminal segment, which is a unique feature within the genus and shared only with some species of Rhipipalloidea. Antennal modifications are compared across the Stilbula clade, of which all are parasitoids of Camponotini (Formicinae). A phylogenetic hypothesis for the group is proposed based on an analysis of 28S and 18S sequence data for 28 species. Ramose antennae are derived independently in both males and females across the clade, but with fully ramose female antennae restricted to the New World prolata group of Pseudochalcura and to some species of the Old World genus Rhipipalloidea. A sister group relationship between these genera is proposed based on both morphological and molecular data. Female antennae in other species of these genera, and other genera in the clade are at most dorsally lobate or serrate, but more commonly cylindrical. Monophyly of species of Obeza and Lophyrocera is supported and linked to a behavioral trait of ovi-position into fruits as opposed to flower heads or leaf buds. Within the Stilbula clade, a dichotomy between New and Old World taxa suggest relatively recent post-Miocene exchanges across the Northern Hemisphere.Fil: Heraty, John Michael. University of California; Estados UnidosFil: Heraty, Joanne M.. University of California; Estados UnidosFil: Torrens, Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de Catamarca. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Secretaría de Industria y Minería. Servicio Geológico Minero Argentino. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Provincia de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja; Argentin

Maize Germplasm Conservation in Southern California's Urban Gardens: Introduced Diversity Beyond ex situ and in situ Management.

Contemporary germplasm conservation studies largely focus on ex situ and in situ management of diversity within centers of genetic diversity. Transnational migrants who transport and introduce landraces to new locations may catalyze a third type of conservation that combines both approaches. Resulting populations may support reduced diversity as a result of evolutionary forces such as genetic drift, selection, and gene flow, yet they may also be more diverse as a result of multiple introductions, selective breeding and cross pollination among multiple introduced varietals. In this study, we measured the amount and structure of maize molecular genetic diversity in samples collected from home gardens and community gardens maintained by immigrant farmers in Southern California. We used the same markers to measure the genetic diversity and structure of commercially available maize varieties and compared our data to previously reported genetic diversity statistics of Mesoamerican landraces. Our results reveal that transnational dispersal creates an opportunity for the maintenance of maize genetic diversity beyond its recognized centers of diversity

Description of the species of Dicoelothorax Ashmead (Chalcidoidea, Eucharitidae) and biology of D. platycerus Ashmead

Descriptions of the adults of the two species of Dicoelothorax Ashmead, Dicoelothorax parviceps and Dicoelothorax platycerus, and the eggs, planidia and pupae of Dicoelothorax platycerus Ashmead are provided. Females of Dicoelothorax platycerus deposit their eggs on the underside of leaves of Pseudabutilon virgatum (Cav.) Fryxell (Malvaceae). The host of Dicoelothorax platycerus is Ectatomma brunneum Smith (Formicidae: Ectatomminae).Fil: Torrens, Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Cientificas y Transferencia Tecnológica de Anillaco; ArgentinaFil: Heraty, John M.. University of California; Estados Unido

AN OVERVIEW OF THE CLASSIFICATION AND EVOLUTION OF THE MAJOR SCARAB BEETLE CLADES (COLEOPTERA: SCARABAEOIDEA) BASED ON PRELIMINARY MOLECULAR ANALYSES

We present a preliminary overview of our molecular phylogenetics research on the superfamily Scarabaeoidea. The molecular data consists of 28S ribosomal DNA sequences (mainly D2 and D3 expansion regions) for over 600 taxa and 18S ribosomal DNA sequences (mainly E17 to E35 expansion regions) for over 150 representative taxa within the lineages sampled. Based on our preliminary molecular phylogenetic results, Scarabaeoidea includes three major groups: 1) Geotrupidae, Passalidae, and Pleocomidae; 2) Lucanidae, Diphyllostomatidae, Trogidae, and Glaresidae; and 3) Hybosoridae, Ochodaeidae, Glaphyridae, and Scarabaeidae. The broad evolutionary patterns within the Scarabaeoidea are discussed with respect to phylogeny and evolution

The impact of FAN1 on a CRISPR-Cas9 gene editing approach for Huntington’s Disease

Fifteen neurodegenerative or neuromuscular diseases are caused by expanded CAG/CTG repeats at multiple loci, all of which are without disease-modifying treatment. One example is Huntington’s disease (HD), an autosomal dominant disease caused by an expanded CAG repeat within exon one of the HTT gene. In HD the length of the CAG repeat tract is inversely correlated with the age at onset, however, recent genome-wide association studies have identified several genetic modifiers of disease. One such modifier was mapped to the region containing FAN1. FAN1, a DNA repair nuclease, is thought to provide protection against somatic expansion with loss-of-function variants associated with an earlier age of HD onset. Our laboratory has previously described a potential therapeutic approach for CAG/CTG diseases. This involves a CRISPR-Cas9 D10A nickase gene editing system, that is capable of contracting expanded repeats in human cell-lines, to nonpathogenic lengths. Given the central role of FAN1 in protecting against somatic expansion, the aim of this thesis was to characterise whether FAN1 modulates CRISPR-Cas9-induced contractions. This is important for not only understanding which proteins are involved in generating or preventing nickase-induced contractions but also for patient stratification to identify patients which would benefit from this therapy. This thesis demonstrates that in a HEK293 reporter cell line knocked out for FAN1, there is an increase in Cas9 nickase-induced contractions, relative to FAN1+/+ cells. This indicates that FAN1 acts to protect against the induction of contractions. Furthermore, this protective role for FAN1 requires FAN1 binding at CAG/CTG repeats, as a DNA-binding mutant identified was not capable of rescuing contractions to FAN1+/+ levels. Additional functional domains of FAN1, including the nuclease and UBZ-binding domains are also implicated. Follow-up validation of HD-patient derived iPSC lines has been described in an effort to characterise whether this protective phenotype is recapitulated iPSC-derived neurons

Crops gone wild: evolution of weeds and invasives from domesticated ancestors.

The evolution of problematic plants, both weeds and invasives, is a topic of increasing interest. Plants that have evolved from domesticated ancestors have certain advantages for study. Because of their economic importance, domesticated plants are generally well-characterized and readily available for ecogenetic comparison with their wild descendants. Thus, the evolutionary history of crop descendants has the potential to be reconstructed in some detail. Furthermore, growing crop progenitors with their problematic descendants in a common environment allows for the identification of significant evolutionary differences that correlate with weediness or invasiveness. We sought well-established examples of invasives and weeds for which genetic and/or ethnobotanical evidence has confirmed their evolution from domesticates. We found surprisingly few cases, only 13. We examine our list for generalizations and then some selected cases to reveal how plant pests have evolved from domesticates. Despite their potential utility, crop descendants remain underexploited for evolutionary study. Promising evolutionary research opportunities for these systems are abundant and worthy of pursuit

The pathology of embryo death caused by the male-killing Spiroplasma bacterium in Drosophila nebulosa

BACKGROUND: Inherited bacteria that kill male offspring, male-killers, are known to be common in insects, but little is understood about the mechanisms used by male-killing bacteria to kill males. In this paper we describe the tempo and changes that occur during male-killing by Spiroplasma bacteria in the host Drosophila nebulosa. RESULTS: Spiroplasma infected D. nebulosa males were developmentally retarded from 6–8 h into embryonic development at 25°C, and arrested at between stages 12 and 13 of embryogenesis (10–12 h). Dying males were characterized by a failure to form segments, and ultimately disintegration of the normal oval embryonic shape. Prior to death, dying males exhibited widespread apoptosis, as testified by TUNEL staining. CONCLUSION: The Spiroplasma kills male Drosophila in a narrow developmental period, shortly after the formation of the host dosage compensation complex that is required for male-killing. Male death is preceded by widespread apoptosis, but it is uncertain if this is primary or secondary apoptosis

The hymenopteran tree of life: evidence from protein-coding genes and objectively aligned ribosomal data

Previous molecular analyses of higher hymenopteran relationships have largely been based on subjectively aligned ribosomal sequences (18S and 28S). Here, we reanalyze the 18S and 28S data (unaligned about 4.4 kb) using an objective and a semi-objective alignment approach, based on MAFFT and BAli-Phy, respectively. Furthermore, we present the first analyses of a substantial protein-coding data set (4.6 kb from one mitochondrial and four nuclear genes). Our results indicate that previous studies may have suffered from inflated support values due to subjective alignment of the ribosomal sequences, but apparently not from significant biases. The protein data provide independent confirmation of several earlier results, including the monophyly of non-xyelid hymenopterans, Pamphilioidea + Unicalcarida, Unicalcarida, Vespina, Apocrita, Proctotrupomorpha and core Proctotrupomorpha. The protein data confirm that Aculeata are nested within a paraphyletic Evaniomorpha, but cast doubt on the monophyly of Evanioidea. Combining the available morphological, ribosomal and protein-coding data, we examine the total-evidence signal as well as congruence and conflict among the three data sources. Despite an emerging consensus on many higher-level hymenopteran relationships, several problems remain unresolved or contentious, including rooting of the hymenopteran tree, relationships of the woodwasps, placement of Stephanoidea and Ceraphronoidea, and the sister group of Aculeata