Blueprint for a high-performance biomaterial: full-length spider dragline silk genes.

Spider dragline (major ampullate) silk outperforms virtually all other natural and manmade materials in terms of tensile strength and toughness. For this reason, the mass-production of artificial spider silks through transgenic technologies has been a major goal of biomimetics research. Although all known arthropod silk proteins are extremely large (>200 kiloDaltons), recombinant spider silks have been designed from short and incomplete cDNAs, the only available sequences. Here we describe the first full-length spider silk gene sequences and their flanking regions. These genes encode the MaSp1 and MaSp2 proteins that compose the black widow's high-performance dragline silk. Each gene includes a single enormous exon (>9000 base pairs) that translates into a highly repetitive polypeptide. Patterns of variation among sequence repeats at the amino acid and nucleotide levels indicate that the interaction of selection, intergenic recombination, and intragenic recombination governs the evolution of these highly unusual, modular proteins. Phylogenetic footprinting revealed putative regulatory elements in non-coding flanking sequences. Conservation of both upstream and downstream flanking sequences was especially striking between the two paralogous black widow major ampullate silk genes. Because these genes are co-expressed within the same silk gland, there may have been selection for similarity in regulatory regions. Our new data provide complete templates for synthesis of recombinant silk proteins that significantly improve the degree to which artificial silks mimic natural spider dragline fibers

What\u27s Right With the Rorschach?

In the present article, we discuss the validity and clinical utility of the Rorschach as a measure of intelligence, thought disorder, and other psychological characteristics. We also summarize potential uses of the test in research and psychotherapy. Controversy has surrounded the Rorschach throughout most of its history, not because it is worthless, but because it has so often been used for the wrong purposes

Gene content evolution in the arthropods

Arthropods comprise the largest and most diverse phylum on Earth and play vital roles in nearly every ecosystem. Their diversity stems in part from variations on a conserved body plan, resulting from and recorded in adaptive changes in the genome. Dissection of the genomic record of sequence change enables broad questions regarding genome evolution to be addressed, even across hyper-diverse taxa within arthropods. Using 76 whole genome sequences representing 21 orders spanning more than 500 million years of arthropod evolution, we document changes in gene and protein domain content and provide temporal and phylogenetic context for interpreting these innovations. We identify many novel gene families that arose early in the evolution of arthropods and during the diversification of insects into modern orders. We reveal unexpected variation in patterns of DNA methylation across arthropods and examples of gene family and protein domain evolution coincident with the appearance of notable phenotypic and physiological adaptations such as flight, metamorphosis, sociality, and chemoperception. These analyses demonstrate how large-scale comparative genomics can provide broad new insights into the genotype to phenotype map and generate testable hypotheses about the evolution of animal diversity

Allergic fungal sinusitis secondary to Acremonium species causing unilateral visual loss

A wide range of fungi have been associated with Allergic Fungal Sinusitis (AFS) or Eosinophilic fungal rhinosinusitis ( EFRS) as it is known in some institutions. To our knowledge, this is the first reported case of aggressive, invasive AFS due to Acremonium species occurring in an immunocompetent patient and leading to unilateral visual loss. Literature on AFS is reviewed.Key words: Eosinophilic fungal rhinosinusitis, Allergic fungal sinusitis, Acremonium species, visual loss

Roots of the Rorschach Controversy

The controversy surrounding the Rorschach is updated, and an analysis of its dynamics is offered. Results on normative data and validity are reviewed, followed by a summary of, and rebuttal to, arguments made by Rorschach advocates. We argue that the current controversy can be traced, at least in part, to two unwarranted beliefs. First is the belief that informal impressions and popularity provide dependeable evidence for evaluating test validity. Second is the belief that Rorschach scores with low individual validity are likely to yield much higher levels of validity if they are interpreted in combination with each other, or with other sources of information, by experts. After presenting historical background information, we show how several arguments made recently in defense of the test reflect these two beliefs, even though they are contradicted by research findings. We conclude that a variety of other divisive conflicts in clinical psychology are related to the inappropriate weight placed on informal and unsystematic impressions relative to systematic research

Effective use of projective techniques in clinical practice: Let the data help with selection and interpretation

By learning about the validity of individual test scores, psychologists can avoid using scores that are invalid and making judgments that are potentially harmful to their clients. This is important not only for improving clinical and forensic practice but also for avoiding lawsuits. In this article, the effective use of projective techniques is described, with attention to the overperception of psychopathology, diagnosis and the description of symptoms, and the detection of child abuse. Guidelines are offered for using the Rorschach, Thematic Apperception Test, human figure drawings, and the Washington University Sentence Completion Test

Conservation of a pH-sensitive structure in the C-terminal region of spider silk extends across the entire silk gene family

Spiders produce multiple silks with different physical properties that allow them to occupy a diverse range of ecological niches, including the underwater environment. Despite this functional diversity, past molecular analyses show a high degree of amino acid sequence similarity between C-terminal regions of silk genes that appear to be independent of the physical properties of the resulting silks; instead, this domain is crucial to the formation of silk fibres. Here we present an analysis of the C-terminal domain of all known types of spider silk and include silk sequences from the spider Argyroneta aquatica, which spins the majority of its silk underwater. Our work indicates that spiders have retained a highly conserved mechanism of silk assembly, despite the extraordinary diversification of species, silk types and applications of silk over 350 million years. Sequence analysis of the silk C-terminal domain across the entire gene family shows the conservation of two uncommon amino acids that are implicated in the formation of a salt bridge, a functional bond essential to protein assembly. This conservation extends to the novel sequences isolated from A. aquatica. This finding is relevant to research regarding the artificial synthesis of spider silk, suggesting that synthesis of all silk types will be possible using a single process

Structural Characterization of Minor Ampullate Spidroin Domains and Their Distinct Roles in Fibroin Solubility and Fiber Formation

10.1371/journal.pone.0056142PLoS ONE82

From fibres to adhesives: evolution of spider capture threads from web anchors by radical changes in silk gland function.

Spider webs that serve as snares are one of the most fascinating and abundant type of animal architectures. In many cases they include an adhesive coating of silk lines-so-called viscid silk-for prey capture. The evolutionary switch from silk secretions forming solid fibres to soft aqueous adhesives remains an open question in the understanding of spider silk evolution. Here we functionally and chemically characterized the secretions of two types of silk glands and their behavioural use in the cellar spider, Pholcus phalangioides. Both being derived from the same ancestral gland type that produces fibres with a solidifying glue coat, the two types produce respectively a quickly solidifying glue applied in thread anchorages and prey wraps, or a permanently tacky glue deployed in snares. We found that the latter is characterized by a high concentration of organic salts and reduced spidroin content, showing up a possible pathway for the evolution of viscid properties by hygroscopic-salt-mediated hydration of solidifying adhesives. Understanding the underlying molecular basis for such radical switches in material properties not only helps to better understand the evolutionary origins and versatility of ecologically impactful spider web architectures, but also informs the bioengineering of spider silk-based products with tailored properties

A Polychaete’s Powerful Punch: Venom Gland Transcriptomics of Glycera Reveals a Complex Cocktail of Toxin Homologs

© The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. The article attached is the publisher's pdf