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Molecular tools used for the identification of species are heavily reliant on reference DNA sequences and taxonomic annotation. Despite this, there are large gaps in the availability of DNA sequences for many taxonomic groups and for different parts of the globe. Here, a DNA barcode library for the Hymenoptera of New Zealand is presented, based on the COI region for 3,145 sequences assigned to 837 BINs and which represent 231 genera and 236 species. This study provides a DNA barcode for approximately 25% of species and 42% of genera of Hymenoptera in New Zealand. However, when combined with sequences previously deposited in BOLD (a further 170 genera), DNA barcodes are available for 73% of New Zealand Hymenopteran genera. To further increase coverage, future efforts need to focus predominantly on taxa from seven families (Encyrtidae, Pteromalidae s.l., Mymaridae, Eulophidae, Diapriidae, Braconidae and Platygastridae). This database facilitates DNA-based identification of taxa for use in both taxonomic revisions and biodiversity monitoring., Competing Interests: No conflict of interest to declare Disclaimer: This article is (co-)authored by any of the Editors-in-Chief, Managing Editors or their deputies in this journal., (Darren F Ward.)

Ants represent a highly diverse and ecologically important group of insects found in almost all terrestrial ecosystems. A subset of ant species have been widely transported around the globe and invade many natural ecosystems, often out-competing native counterparts and causing varying impacts on recipient ecosystems. Decisions to control non-native ant populations require an understanding of their interactions and related impacts on native communities. We employed stable isotope analysis and metabarcoding techniques to identify potential dietary niche overlap and identify gut contents of 10 ant species found in natural ecosystems in Aotearoa New Zealand. Additionally, we looked at co-occurrence to identify potential competitive interactions among native and non-native ant species. Ants fed mainly across two trophic levels, with high dietary overlap. Relative to other ant species sampled, two non-native ant species, Linepithema humile and Technomyrmex jocosus, were found to feed at the lowest trophic level. The largest isotopic niche overlap was observed between the native Monomorium antarcticum and the invasive Ochetellus glaber, with analyses revealing a negative co-occurrence pattern. Sequence data of ant gut content identified 51 molecular operational taxonomic units, representing 22 orders and 34 families, and primarily consisting of arthropod DNA. Although we generally found high dietary overlap among species, negative occurrence between a dominant, non-native species and a ubiquitous native species indicates that species-specific interactions could be negatively impacting native ecosystems. Our research progresses and informs the currently limited knowledge around establishing protocols for metabarcoding to investigate ant diet and interactions between native and non-native ant species., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

A new genus of Microgastrinae parasitoid wasp endemic to New Zealand, Notogaster gen. nov. Fernández-Triana and Ward, is described, with ten new species: Notogaster avilai sp. nov., N. charlesi sp. nov., N. macdonaldae sp. nov., N. martini sp. nov., N. poultonae sp. nov., N. sucklingi sp. nov., N. toddae sp. nov., N. walkeri sp. nov., N. withersae sp. nov. and N. wornerae sp. nov. Based on some features, Notogaster resembles the genus Pholetesor Mason, although morphological and molecular data reveal they are not closely related. Notogaster is found throughout New Zealand, although many species are predominantly in the South Island. Species have been collected from a range of habitats, elevations, and collecting techniques. No host information is currently available.

In the second paper on New Zealand Tersilochinae (Ichneumonidae) we review two endemic New Zealand genera, Kiwi gen. nov. (eight species) and Zealochus Khalaim (three species). Nine species are described as new to science: Kiwi barrattae sp. nov., K. canterberus sp. nov., K. earlyi sp. nov., K. gronous sp. nov., K. oreteus sp. nov., K. ruzelus sp. nov., K. waitakerus sp. nov., Zealochus abominosus sp. nov. and Z. stepheni sp. nov. Zealochus gauldi Khalaim is transferred to Kiwi (comb. nov.). Identification keys to species of Kiwi and Zealochus occurring in New Zealand are provided.

The Tersilochinae (Ichneumonidae) from New Zealand are revised in part, with three new endemic genera and seventeen new species described: Aotearoazeus gen. nov., A. bullivantus sp. nov., A. coronetus sp. nov., A. probles sp. nov., Barycnellus gen. nov., B. aucklandellus sp. nov., B. conlisus sp. nov., B. cuvierensis sp. nov., B. globosus sp. nov., B. robustus sp. nov., Diaparsis zealandica sp. nov., Gauldiana gen. nov., G. arantia sp. nov., G. aspiringa sp. nov., G. dubia sp. nov., G. kaweka sp. nov., G. minuta sp. nov., G. nigra sp. nov., G. rotoitia sp. nov., and G. triangulata sp. nov. Zealochus postfurcalis is transferred to the genus Gauldiana (comb. nov.). The genus Diaparsis is recorded from New Zealand for the first time. Keys to genera and species of Tersilochinae occurring in New Zealand are provided.

Parasitoid wasps are a mega-diverse, ecologically dominant, but poorly studied component of global biodiversity. In order to maximise the efficiency and reduce the cost of their collection, the application of optimal sampling techniques is necessary. Two sites in Auckland, New Zealand were sampled intensively to determine the relationship between sampling effort and observed species richness of parasitoid wasps from the family Ichneumonidae. Twenty traps were deployed at each site at three different times over the austral summer period, resulting in a total sampling effort of 840 Malaise-trap-days. Rarefaction techniques and non-parametric estimators were used to predict species richness and to evaluate the variation and completeness of sampling. Despite an intensive Malaise-trapping regime over the summer period, no asymptote of species richness was reached. At best, sampling captured two-thirds of parasitoid wasp species present. The estimated total number of species present depended on the month of sampling and the statistical estimator used. Consequently, the use of fewer traps would have caught only a small proportion of all species (one trap 7-21%; two traps 13-32%), and many traps contributed little to the overall number of individuals caught. However, variation in the catch of individual Malaise traps was not explained by seasonal turnover of species, vegetation or environmental conditions surrounding the trap, or distance of traps to one another. Overall the results demonstrate that even with an intense sampling effort the community is incompletely sampled. The use of only a few traps and/or for very short periods severely limits the estimates of richness because (i) fewer individuals are caught leading to a greater number of singletons; and (ii) the considerable variation of individual traps means some traps will contribute few or no individuals. Understanding how sampling effort affects the richness and diversity of parasitoid wasps is a useful foundation for future studies., Competing Interests: Darren Ward is an Academic Editor for PeerJ and an employee of Landcare Research.

Our ability to predict the identity of future invasive alien species is largely based upon knowledge of prior invasion history. Emerging alien species-those never encountered as aliens before-therefore pose a significant challenge to biosecurity interventions worldwide. Understanding their temporal trends, origins, and the drivers of their spread is pivotal to improving prevention and risk assessment tools. Here, we use a database of 45,984 first records of 16,019 established alien species to investigate the temporal dynamics of occurrences of emerging alien species worldwide. Even after many centuries of invasions the rate of emergence of new alien species is still high: One-quarter of first records during 2000-2005 were of species that had not been previously recorded anywhere as alien, though with large variation across taxa. Model results show that the high proportion of emerging alien species cannot be solely explained by increases in well-known drivers such as the amount of imported commodities from historically important source regions. Instead, these dynamics reflect the incorporation of new regions into the pool of potential alien species, likely as a consequence of expanding trade networks and environmental change. This process compensates for the depletion of the historically important source species pool through successive invasions. We estimate that 1-16% of all species on Earth, depending on the taxonomic group, qualify as potential alien species. These results suggest that there remains a high proportion of emerging alien species we have yet to encounter, with future impacts that are difficult to predict., Competing Interests: The authors declare no conflict of interest.

Effective detection plays an important role in the surveillance and management of invasive species. Invasive ants are very difficult to eradicate and are prone to imperfect detection because of their small size and cryptic nature. Here we demonstrate the use of spatially explicit surveillance models to estimate the probability that Argentine ants (Linepithema humile) have been eradicated from an offshore island site, given their absence across four surveys and three surveillance methods, conducted since ant control was applied. The probability of eradication increased sharply as each survey was conducted. Using all surveys and surveillance methods combined, the overall median probability of eradication of Argentine ants was 0.96. There was a high level of confidence in this result, with a high Credible Interval Value of 0.87. Our results demonstrate the value of spatially explicit surveillance models for the likelihood of eradication of Argentine ants. We argue that such models are vital to give confidence in eradication programs, especially from highly valued conservation areas such as offshore islands.

The endemic New Zealand weta is an enigmatic insect. Although the insect is well known by its distinctive name, considerable size, and morphology, many basic aspects of weta biology remain unknown. Here, we employed cultivation-independent enumeration techniques and rRNA gene sequencing to investigate the gut microbiota of the Auckland tree weta (Hemideina thoracica). Fluorescence in situ hybridisation performed on different sections of the gut revealed a bacterial community of fluctuating density, while rRNA gene-targeted amplicon pyrosequencing revealed the presence of a microbial community containing high bacterial diversity, but an apparent absence of archaea. Bacteria were further studied using full-length 16S rRNA gene sequences, with statistical testing of bacterial community membership against publicly available termite- and cockroach-derived sequences, revealing that the weta gut microbiota is similar to that of cockroaches. These data represent the first analysis of the weta microbiota and provide initial insights into the potential function of these microorganisms.

An overview of Cynipoidea (Hymenoptera) in New Zealand is presented with information on families, genera, and when available, species. Notes on their distribution, biology, and a taxonomic key are provided. The New Zealand cynipoid fauna is very poorly known, with only 11 described species, and five genus-only taxa. The fauna is dominated by introduced species; two species have been deliberately introduced as biological control agents, and at least 12 taxa are definitely or probably adventives. Many of these species are widespread and collected from modified and non-native habitats. New generic records of Figitidae for New Zealand include: Xyalaspis (Anacharitinae), Ganaspis, (Eucoilinae), and Thoreauella (Emargininae), all of which are considered adventives. There are no native species of gall forming wasps (Cynipidae) in New Zealand, and only two native species of Figitidae are present: Anacharis zealandica Ashmead, 1900 and Kleidotoma subantarcticana Yoshimoto, 1964.

The prey range of the invasive Asian paper wasp, Polistes chinensis antennalis, was studied using molecular diagnostics. Nests of paper wasps were collected from urban residential and salt marsh habitats, larvae were removed and dissected, and DNA in the gut of the paper wasp larvae was amplified and sequenced with cytochrome c oxidase subunit I (COI). Seventy percent of samples (211/299) yielded medium-to high-quality sequences, and prey identification was achieved using BLAST searches in BOLD. A total of 42 taxa were identified from 211 samples. Lepidoptera were the majority of prey, with 39 taxa from 91% of samples. Diptera was a relatively small component of prey (three taxa, 19 samples). Conclusive species-level identification of prey was possible for 67% of samples, and genus-level identification, for another 12% of samples. The composition of prey taken was different between the two habitats, with 2.5× more native prey species being taken in salt marsh compared with urban habitats. The results greatly extend the prey range of this invasive species. The technique is a more effective and efficient approach than relying on the collection of "prey balls", or morphological identification of prey, for the study of paper wasps.

Microgastrine wasps are among the most species-rich and numerous parasitoids of caterpillars (Lepidoptera). They are often host-specific and thus are extensively used in biological control efforts and figure prominently in trophic webs. However, their extraordinary diversity coupled with the occurrence of many cryptic species produces a significant taxonomic impediment. We present and release the results of 8 years (2004-2011) of DNA barcoding microgastrine wasps. Currently they are the best represented group of parasitoid Hymenoptera in the Barcode of Life Data System (BOLD), a massive barcode storage and analysis data management site for the International Barcoding of Life (iBOL) program. There are records from more than 20 000 specimens from 75 countries, including 50 genera (90% of the known total) and more than 1700 species (as indicated by Barcode Index Numbers and 2% MOTU). We briefly discuss the importance of this DNA data set and its collateral information for future research in: (1) discovery of cryptic species and description of new taxa; (2) estimating species numbers in biodiversity inventories; (3) clarification of generic boundaries; (4) biological control programmes; (5) molecular studies of host-parasitoid biology and ecology; (6) evaluation of shifts in species distribution and phenology; and (7) fostering collaboration at national, regional and world levels. The integration of DNA barcoding with traditional morphology-based taxonomy, host records, and other data has substantially improved the accuracy of microgastrine wasp identifications and will significantly accelerate further studies on this group of parasitoids., (© 2012 Blackwell Publishing Ltd.)

A new genus of Microgastrinae, Shireplitis Fernández-Triana and Ward, is described as endemic from New Zealand. Shireplitis resembles the Holarctic genus Paroplitis Mason, although morphological and molecular data reveal they are not likely to be closely related but are an example of convergent evolution. Shireplitis comprises species mostly found in moss, litter, or tussock grasslands, usually at moderate altitude on several New Zealand mountain ranges. Keys to all species from both genera are provided. Seven new species are described: Paroplitis vietnamensis van Achterberg and Fernández-Triana, and six Shireplitis species authored by Fernández-Triana and Ward: S. bilboi, S. frodoi, S. meriadoci, S. peregrini, S. samwisei and S. tolkieni.

Natural History Collections (NHCs) play a central role as sources of data for biodiversity and conservation. Yet, few NHCs have examined whether the data they contain is adequately representative of local biodiversity. I examined over 15,000 databased records of Hymenoptera from 1435 locations across New Zealand collected over the past 90 years. These records are assessed in terms of their geographical, temporal, and environmental coverage across New Zealand. Results showed that the spatial coverage of records was significantly biased, with the top four areas contributing over 51% of all records. Temporal biases were also evident, with a large proportion (40%) of records collected within a short time period. The lack of repeat visits to specific locations indicated that the current set of NHC records would be of limited use for long-term ecological research. Consequently, analyses and interpretation of historical data, for example, shifts in community composition, would be limited. However, in general, NHC records provided good coverage of the diversity of New Zealand habitats and climatic environments, although fewer NHC records were represented at cooler temperatures (<5°C) and the highest rainfalls (>5000 mm/yr). Analyses of NHCs can be greatly enhanced by using simple techniques that examine collection records in terms of environmental and geographical space. NHCs that initiate a systematic sampling strategy will provide higher quality data for biodiversity research than ad hoc or point samples, as is currently the norm. Although NHCs provide a rich source of information they could be far better utilised in a range of large-scale ecological and conservation studies.

The overall mechanisms governing the role of laminins during osteogenic differentiation of human mesenchymal stem cells (hMSC) are poorly understood. We previously reported that laminin-332 induces an osteogenic phenotype in hMSC and does so through a focal adhesion kinase (FAK) and extracellular signal-related kinase (ERK) dependent pathway. We hypothesized that this is a result of integrin-ECM binding, and that it occurs via the known alpha3 LG3 integrin binding domain of laminin-332. To test this hypothesis we cultured hMSC on several different globular domains of laminin-332. hMSC adhered best to the LG3 domain, and this adhesion maximally activated FAK and ERK within 120 min. Prolonged culturing (8 or 16 days) of hMSC on LG3 led to activation of the osteogenic transcription factor Runx2 and expression of key osteogenic markers (osterix, bone sialoprotein 2, osteocalcin, alkaline phosphatase, extracellular calcium) in hMSC. LG3 domain binding did not increase matrix mineralization, demonstrating that the LG3 domain alone is not sufficient to induce complete osteogenic differentiation in vitro. We conclude that the LG3 domain mediates attachment of hMSC to laminin-332 and that this adhesion recapitulates most, but not all, of the osteogenic differentiation associated with laminin-5 binding to hMSC.

Focal adhesion kinase (FAK) is a key integrator of integrin-mediated signals from the extracellular matrix to the cytoskeleton and downstream signaling molecules. FAK is activated by phosphorylation at specific tyrosine residues, which then stimulate downstream signaling including the ERK1/2 pathway, leading to a variety of cellular responses. In this study, we examined the effects of FAK point mutations at tyrosine residues (Y397, Y925, Y861, and Y576/7) on osteogenic differentiation of human mesenchymal stem cells exposed to collagen I and cyclic tensile strain. Our results demonstrate that FAK signaling emanating from Y397, Y925, and to a lesser extent Y576/7, but not from Y861, controls osteogenic differentiation through an ERK1/2 pathway, as measured by expression levels of key osteogenesis marker genes and subsequent matrix mineralization. These data indicate that FAK is a critical decision maker in extracellular matrix/strain-enhanced osteogenic differentiation.

Human mesenchymal stem cells (hMSCs) are a population of multipotent bone marrow cells capable of differentiating along multiple lineages, including bone. Our recently published proteomics studies suggest that focusing of gene expression is the basis of hMSC osteogenic transdifferentiation, and that extracellular matrix proteins play an important role in controlling this focusing. Here, we show that application of a 3-5% tensile strain to a collagen I substrate stimulates osteogenesis in the attached hMSCs through gene focusing via a MAP kinase signaling pathway. Mechanical strain increases expression levels of well-established osteogenic marker genes while simultaneously reducing expression levels of marker genes from three alternate lineages (chondrogenic, adipogenic, and neurogenic). Mechanical strain also increases matrix mineralization (a hallmark of osteogenic differentiation) and activation of extracellular signal-related kinase 1/2 (ERK). Addition of the MEK inhibitor PD98059 to reduce ERK activation decreases osteogenic gene expression and matrix mineralization while also blocking strain-induced down-regulation of nonosteogenic lineage marker genes. These results demonstrate that mechanical strain enhances collagen I-induced gene focusing and osteogenic differentiation in hMSCs through the ERK MAP kinase signal transduction pathway.

One of the hallmark events regulating the process of osteogenesis is the transition of undifferentiated human mesenchymal stem cells (hMSCs) found in the bone marrow into mineralized-matrix producing osteoblasts (hOSTs) through mechanisms that are not entirely understood. With recent developments in mass spectrometry and its potential application to the systematic definition of the stem cell proteome, proteins that govern cell fate decisions can be identified and tracked during this differentiation process. We hypothesize that protein profiling of hMSCs and hOSTs will identify potential osteogenic marker proteins associated with hMSC commitment and hOST differentiation. To identify markers for each cell population, we analyzed the expression of hMSC proteins and compared them to that of hOST by two-dimensional gel electrophoresis and two-dimensional liquid chromatography tandem mass spectrometry (2D LC-MS/MS). The 2D LC-MS/MS data sets were analyzed using the Database for Annotation, Visualization and Integrated Discovery (DAVID). Only 34% of the spots in 2D gels were found in both cell populations; of those that differed between populations, 65% were unique to hOST cells. Of the 755 different proteins identified by 2D LCMS/ MS in both cell populations, two sets of 247 and 158 proteins were found only in hMSCs and hOST cells, respectively. Differential expression of some of the identified proteins was further confirmed by Western blot analyses. Substantial differences in clusters of proteins responsible for calcium- based signaling and cell adhesion were found between the two cell types. Osteogenic differentiation is accompanied by a substantial change in the overall protein expression profile of hMSCs. This study, using gene ontology analysis, reveals that these changes occur in clusters of functionally related proteins. These proteins may serve as markers for identifying stem cell differentiation into osteogenic fates because they promote differentiation by mechanisms that remain to be defined.

Since March 1989, intramuscular (IM) promethazine has been successfully used to treat the symptoms of space motion sickness. The incidence of sedation associated with promethazine administration on the ground is large and may result in operational impact. The authors undertook a retrospective study to quantify the incidence of sedation from promethazine use during Space Shuttle flights. Crew medical debriefings from 14 shuttle missions were reviewed for crew members who had been treated with IM promethazine and their corresponding symptoms were identified. Twenty-one crew members received IM promethazine (25-50 mg), and only one experienced any associated sedation with no operational impact. This sedation incidence of less that 5% is in stark contrast to the 60 to 73% incidence of sedation seen in ground-based studies. The incidence of sedation during space flight from IM promethazine is substantially less than that seen on the ground and does not present an operational problem during Space Shuttle flights. Future investigations of environmental stressors and pharmacodynamic changes associated with space flight may explain the huge disparity between the space-flight and ground-based data.

Shuttle astronauts currently drink approximately a quart of water with eight salt tablets before reentry to restore lost body fluid and thereby reduce the likelihood of cardiovascular instability and syncope during reentry and after landing. However, the saline loading countermeasure is not entirely effective in restoring orthostatic tolerance to preflight levels. We tested the hypothesis that the effectiveness of this countermeasure could be improved with the use of a vasopressin analog, 1-deamino-8-D-arginine vasopressin (dDAVP). The rationale for this approach is that reducing urine formation with exogenous vasopressin should increase the magnitude and duration of the vascular volume expansion produced by the saline load, and in so doing improve orthostatic tolerance during reentry and postflight.

A dramatic improvement in full skin thickness burn wounds in rats treated intravenously with the non-ionic surfactant Pluronic F-127 (F-127) has been demonstrated. In this study the F-127 was given 30 min postburn to simulate conditions encountered in a clinical setting. Anaesthetized male rats (300-320 g) received full skin thickness burns by immersion of the anterior chest wall (8 per cent body surface area in a 70 degrees C water-bath for 12 s). Burn wound area was measured immediately and after 48 h. Thirty minutes after the burn, half the animals received equal volumes (8 ml/kg body wt) of either saline or F-127 (12 mM/l concentration) via the tail vein. The animals autopsied at 48 h showed a significant (P < 0.05) reduction in the degree of wound contraction and the wound appeared grossly less damaged in the F-127-treated animals. Histologically, skin biopsies showed less of the microscopic damage usually associated with full skin thickness burns in the F-127-treated animals than in the saline controls. We also used thermography to measure skin temperature of the burn area at 90 min and 48 h postinjury demonstrating alterations in the F-127-treated animals (P < 0.05). In animals followed for 30 days postinjury, there was a significant (P < 0.01) improvement in the wound closure rates in the F-127-treated animals. These observations show a positive therapeutic effect of F-127 on the inflammatory process in the area of a burn that may improve wound healing.

The Escherichia coli Nus factors act in conjunction with the bacteriophage lambda N protein to suppress transcription termination on the lambda chromosome. NusA binds both N and RNA polymerase and may also interact with other Nus factors. To search for additional components of the N antitermination system, we isolated host revertants that restored N activity in nusA1 mutants. One revertant, nusG4, was mapped to the rif region of the E. coli chromosome and shown to represent a point mutation near the 3' end of the nusG gene. The nusG4 mutation also suppressed nusE71 but not nusASal, nusB5, nusC60 (rpoB60), or nusD026 (rho026). However, nusG+ expressed from a multicopy plasmid suppressed nusD026 and related rho mutants for both lambda and phage T4 growth. These results suggest that NusG may act as a component of the N antitermination complex. In addition, the data imply a role for NusG in Rho-dependent termination.

CLONE 3 is a microcomputer software program which draws circular and linear plasmid maps, facilitates cloning operations and performs related sequence analysis and information retrieval functions. This article describes the use of the CLONE 3 program to streamline the flow of information in the research laboratory doing genetic engineering applications.

The promoter of the polA gene of Escherichia coli K-12 was fused to the lacZ gene by selecting deletions within a lambda lacZ polA transducing phage. Four fusions, deleting varying amounts of the polA gene, were characterized. The polA promoter was found to be approximately 3% as active as the fully induced lac promoter. This figure is compatible with the normal intracellular level of deoxyribonucleic acid polymerase I. No evidence was found for outogenous regulation of transcription from the polA promoter. Expression from this promoter was influenced by neither recA nor mitomycin C, but uvrD and uvrE mutations reduced expression slightly.

A 19-year-old woman, recently discharged from the hospital and being treated for schizophrenia, presented with an unusual reaction to trifluoperazine. She complained of nausea and vomiting and experienced bilateral swelling of the tongue. Symptoms subsided when the medication was discontinued. Although dystonic reactions to high doses of phenothiazines are not uncommon, we postulate that this case represented an unusual allergic reaction to the medication.

The nusA1 and nusB5 mutations in a partial suppression of polarity and thus transcription termination in Escherichia coli. As these mutations block the transcription antitermination activity of bacteriophage lambda N gene product, they paradoxically seem to enhance transcription termination at phage termination sites. The rho mutation HDF026 displays almost identical properties. The observations suggest that the nusA and nusB gene products may act as termination factors analogous to rho protein.

A method for measuring the mechanical fragility of red blood cells suitable for use in small laboratory animals, such as rats, is reported because of lack of such data in the literature. Whole blood is mixed with phosphate buffered saline in a tube containing glass beads. The tubes are rocked for 90 minutes, centrifuged and the percent hemolysis determined. Varying the osmolality of the saline suspending medium had little effect on the mechanical fragility of rat red cells prior to the NaCl concentrations at which a significant change in osmotic hemolysis occurred. The duration of rocking increased the mechanical fragility. Varying the pH (6.4-8.0) had no effect. The size of the glass beads changed the mechanical fragility as did varying temperature. The mean mechanical fragility of rat red blood cells was 46% hemolysis (80 adult male animals). Because of the small volume of blood required with this method, mechanical fragility of red cells of other small laboratory animals also may be determined.

The bacteriophage lambda N gene product positively controls development by preventing termination of transcription at terminator sites critical to the sequential expression of phage genes. Many host transcription factors, including RNA polymerase, are involved in N gene action. Recent findings have shown that ribosomal proteins are also involved. The current understanding of how the N protein affects transcription termination is reviewed, and a possible model and current problems are discussed.

The bacteriophage lambda N protein regulates phage development by selectively suppressing transcription termination in its host, Escherichia coli. The E. coli nus mutants prevent N activity. To provide additional information on transcription termination, we have isolated pseudo-revertants of the nusA1 mutation that restore lambda N function. One series of pseudo-revertants lie in the E. coli nusB gene, whose product is normally required for lambda N activity. These mutations are N-specific: mutations that restore lambda N activity do not restore the activity of the analogous N protein of phage 21. Similarly, nusB mutations that restore phage 21 N function are deficient for lambda N function. Mapping of the two classes of mutation is consistent with their location in two distinct domains in the nusB protein. We discuss whether nusB is specific for N protein or for some other component of this regulation system, e.g. the phage site (nut) required for N action.

We describe a plasmid map program which runs on an IBM PC microcomputer and facilitates the drawing of circular plasmid maps. The user enters information from the keyboard in the form of restriction enzyme sites, genes and their locations, and other plasmid markers such as promoters, origins, or other sites. This information can then be stored in a file for future reference. The plasmid map can be displayed on the screen, printed on a dot-matrix printer, or plotted on a Hewlett Packard HP7475A plotter.

From a strain lacking adenyl cyclase and the catabolite-sensitive gene activator protein, two mutants were isolated that can synthesize tryptophanase. Each mutation is extremely closely linked to the tryptophanase structural gene. The mutations differ from one another in the rate of synthesis of tryptophanase that they permit in the genetic background in which they were isolated; they differ from one another and also from the wild type in the maximum rate of synthesis of tryptophanase that they permit in a genetic background with intact adenyl cyclase and catabolite-sensitive gene activator protein. Both mutations appear to lie in the tryptophanase promoter.

A phage lambda cloning vector has been constructed which contains a single site for the restriction endonuclease BamHI. Since Sau3A and Bg/II produce the same cohesive ends as BamHI, this vector can also be used to clone DNA fragments generated with either of these enzymes. We have used this vector to construct an Escherichia coli library using partial digestion with Sau3A. This vector will be most useful for applications requiring genetic analysis of cloned E. coli genes.