A new role for PGRP-S (Tag7) in immune defense: lymphocyte migration is induced by a chemoattractant complex of Tag7 with Mts1

PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4⁺ and CD8⁺ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response.     

Genomic organization and amplification of the human keratin 15 and keratin 19 genes

Keratin intermediate filaments are the major components of the cytoskeleton in epithelial cells. Mutations in keratin genes have been documented in many disorders of the skin, nails, hair, and mucous membranes. Although no mutations have been described in either keratin 15 or keratin 19, they are good candidates for other as yet uncharacterized genetic disorders of keratinization, particularly as the skin, nails, hair, and conjunctiva are sites of keratin 15 and 19 expression. To facilitate future mutation detection analyses, we have therefore characterized the intron-exon organization of the human keratin 15 and keratin 19 genes. The keratin 15 gene comprises 8 exons spanning approximately 5.1 kb on 17q21, and the keratin 19 gene consists of 6 exons covering approximately 4.7 kb on 17q21. We have also developed a PCR-based mutation detection strategy using primers placed on flanking introns followed by direct sequencing of the PCR products.     

PHOTOSYNTHETIC PIGMENT AND GENETIC DIFFERENCES BETWEEN TWO SOUTHERN OCEAN MORPHOTYPES OF EMILIANIA HUXLEYI (HAPTOPHYTA)1

The widespread coccolithophorid Emiliania huxleyi (Lohmann) W. W. Hay et H. Mohler plays a pivotal role in the carbon pump and is known to exhibit significant morphological, genetic, and physiological diversity. In this study, we compared photosynthetic pigments and morphology of triplicate strains of Southern Ocean types A and B/C. The two morphotypes differed in width of coccolith distal shield elements (0.11–0.24 μm, type A; 0.06–0.12 μm, type B/C) and morphology of distal shield central area (grill of curved rods in type A; thin plain plate in type B/C) and showed differences in carotenoid composition. The mean 19′‐hexanoyloxyfucoxanthin (Hex):chl a ratio in type B/C was >1, whereas the type A ratio was <1. The Hex:fucoxanthin (fuc) ratio for type B/C was 11 times greater than that for type A, and the proportion of fuc in type A was 6 times higher than that in type B/C. The fuc derivative 4‐keto‐19′‐hexanoyloxyfucoxanthin (4‐keto‐hex) was present in type A but undetected in B/C. DNA sequencing of tufA distinguished morphotypes A, B/C (indistinguishable from B), and R, while little variation was observed within morphotypes. Thirty single nucleotide polymorphisms were identified in the 710 bp tufA sequence, of which 10 alleles were unique to B/C and B morphotypes, seven alleles were unique to type A, and six alleles were unique to type R. We propose that the morphologically, physiologically, and genetically distinct Southern Ocean type B/C sensu Young et al. (2003) be classified as E. huxleyi var. aurorae var. nov. S. S. Cook et Hallegr.     

Australian Dust Storm Associated with Extensive Aspergillus sydowii Fungal “Bloom” in Coastal Waters

A massive central Australian dust storm in September 2009 was associated with abundant fungal spores (150,000/m³) and hyphae in coastal waters between Brisbane (27°S) and Sydney (34°S). These spores were successfully germinated from formalin-preserved samples, and using molecular sequencing of three different genes (the large subunit rRNA gene [LSU], internal transcribed spacer [ITS[, and beta-tubulin gene), they were conclusively identified as Aspergillus sydowii, an organism circumstantially associated with gorgonian coral fan disease in the Caribbean. Surprisingly, no human health or marine ecosystem impacts were associated with this Australian dust storm event. Australian fungal cultures were nontoxic to fish gills and caused a minor reduction in the motility of Alexandrium or Chattonella algal cultures but had their greatest impacts on Symbiodinium dinoflagellate coral symbiont motility, with hyphae being more detrimental than spores. While we have not yet seen any soft coral disease outbreaks on the Australian Great Barrier Reef similar to those observed in the Caribbean and while this particular fungal population was non- or weakly pathogenic, our observations raise the possibility of future marine ecosystem pathogen impacts from similar dust storms harboring more pathogenic strains.     

High-throughput genotyping of hop (Humulus lupulus L.) utilising diversity arrays technology (DArT)

Implementation of molecular methods in hop (Humulus lupulus L.) breeding is dependent on the availability of sizeable numbers of polymorphic markers and a comprehensive understanding of genetic variation. However, use of molecular marker technology is limited due to expense, time inefficiency, laborious methodology and dependence on DNA sequence information. Diversity arrays technology (DArT) is a high-throughput cost-effective method for the discovery of large numbers of quality polymorphic markers without reliance on DNA sequence information. This study is the first to utilise DArT for hop genotyping, identifying 730 polymorphic markers from 92 hop accessions. The marker quality was high and similar to the quality of DArT markers previously generated for other species; although percentage polymorphism and polymorphism information content (PIC) were lower than in previous studies deploying other marker systems in hop. Genetic relationships in hop illustrated by DArT in this study coincide with knowledge generated using alternate methods. Several statistical analyses separated the hop accessions into genetically differentiated North American and European groupings, with hybrids between the two groups clearly distinguishable. Levels of genetic diversity were similar in the North American and European groups, but higher in the hybrid group. The markers produced from this time and cost-efficient genotyping tool will be a valuable resource for numerous applications in hop breeding and genetics studies, such as mapping, marker-assisted selection, genetic identity testing, guidance in the maintenance of genetic diversity and the directed breeding of superior cultivars.     

AmylPepPred: Amyloidogenic Peptide Prediction tool

We present an efficient computational architecture designed using supervised machine learning model to predict amyloid fibril forming protein segments, named AmylPepPred. The proposed prediction model is based on bio-physio-chemical properties of primary sequences and auto-correlation function of their amino acid indices. AmylPepPred provides a user friendly web interface for the researchers to easily observe the fibril forming and non-fibril forming hexmers in a given protein sequence. We expect that this stratagem will be highly encouraging in discovering fibril forming regions in proteins thereby benefit in finding therapeutic agents that specifically aim these sequences for the inhibition and cure of amyloid illnesses.

Availability

AmylPepPred is available freely for academic use at www.zoommicro.in/amylpeppred