Pseudo-nitzschia australis Frenguelli is a marine pennate diatom associated with the production of domoic acid- a neuroexcitatory amino acid linked to illness and mortality of humans and wildlife. Distinguishing P. australis from its co-occurring congeners is labor intensive and time consuming because of a requirement for scanning electron microscopy. Here, we apply large-subunit ribosomal RNA (LSU rRNA)-targeted oligonucleotides in whole-cell and sandwich hybridization formats to identify and enumerate this species collected from pure cultures and natural populations. Whole-cell hybridization employed fluorescently labeled probes, filter-based sample processing, and epifluorescence microscopy to enumerate labeled cells. In contrast, sandwich hybridization was accomplished by homogenizing cells in a chaotropic solution and performing two hybridization reactions: capture of LSU rRNA using an oligonucleotide coupled to a macroscopic solid support and binding of signal probe to a region of LSU rRNA near that of the capture site. Sandwich hybrids were detected colorimetrically; color intensity was proportional to the abundance of target species in the original sample. The sandwich hybridization assay was semiautomated with a robotic processor. Both whole-cell and sandwich hybridization are useful techniques for identifying P. australis as it occurs in nature. Sandwich hybridization potentially offers the most rapid and simple means to accomplish this task when screening large numbers of environmental samples.

LSUs (RESPONSE TO LOW SULFUR) are plant-specific proteins of unknown function that were initially identified during transcriptomic studies of the sulfur deficiency response in Arabidopsis. Recent functional studies have shown that LSUs are important hubs of protein interaction networks with potential roles in plant stress responses. In particular, LSU proteins have been reported to interact with members of the brassinosteroid, jasmonate signaling, and ethylene biosynthetic pathways, suggesting that LSUs may be involved in response to plant stress through modulation of phytohormones. Furthermore, in silico analysis of the promoter regions of LSU genes in Arabidopsis has revealed the presence of cis-regulatory elements that are potentially responsive to phytohormones such as ABA, auxin, and jasmonic acid, suggesting crosstalk between LSU proteins and phytohormones. In this review, we summarize current knowledge about the LSU gene family in plants and its potential role in phytohormone responses. [ABSTRACT FROM AUTHOR]

The nonsexual lichenized family Siphulaceae is comprised of the obligately sterile genera, Siphula and Thamnolia. These genera are currently placed in the order Lecanorales, apparently based solely on the character of lichenization since apothecia and other lichen reproductive structures are absent. Using the nucleotide characters of rDNA, we tested the phylogenetic position of these genera among the Ascomycota. Cladistic analyses of SSU nrDNA and partial LSU nrDNA did not support the recognition of the Siphulaceae. Rather, Siphula and Thamnolia represent independent origins of nonsexual lichens among the Icmadophilaceae; a family that is currently classified in the order Helotiales. In addition to these molecular characters, the secondary chemistry of these genera also supports their affinity with the Icmadophilaceae. We propose taxonomically emending the Icmadophilaceae to include the genera Siphula and Thamnolia. The phylogenetic relationships between the Icmadophilaceae and the Baeomycetaceae, the other family of lichenized fungi classified in the Helotiales, are discussed. Cladistic evidence is provided which demonstrates that the Baeomycetaceae is a distinct taxon from the Icmadophilaceae and the two families represent independent lichenization events. The phylogenetic relationships between these families and other higher taxa (e.g., families and orders) of the Ascomycota are also discussed.

The Gambierdiscus genus is a group of benthic dinoflagellates commonly associated with ciguatera fish poisoning (CFP), which is generally found in tropical or sub-tropical regions around the world. Morphologically similar species within the genus can vary in toxicity; however, species identifications are difficult or sometimes impossible using light microscopy. DNA sequencing of ribosomal RNA genes (rDNA) is thus often used to identify and describe Gambierdiscus species and ribotypes, but the expense and time can be prohibitive for routine culture screening and/or large-scale monitoring programs. This study describes a restriction fragment length polymorphism (RFLP) typing method based on analysis of the large subunit rDNA that can successfully identify at least nine of the described Gambierdiscus species and two Fukuyoa species. The software programs DNAMAN 6.0 and Restriction Enzyme Picker were used to identify a set of restriction enzymes (SpeI, HpyCH4IV, and TaqαI) capable of distinguishing most of the known Gambierdiscus species for which DNA sequences were available. This assay was tested using in silico analysis and cultured isolates, and species identifications of isolates assigned by RFLP typing were confirmed by DNA sequencing. To verify the assay and assess intra-specific heterogeneity in RFLP patterns, identifications of 63 Gambierdiscus isolates comprising ten Gambierdiscus species, one ribotype, and two Fukuyoa species were confirmed using RFLP typing, and this method was subsequently employed in the routine identification of isolates collected from the Caribbean Sea. The RFLP assay presented here reduces the time and cost associated with morphological identification via scanning electron microscopy and/or DNA sequencing, and provides a phylogenetically sensitive method for routine Gambierdiscus species assignment.

No summary available.

Thomas E. Patterson’s monumental biography of Huey Long is a profound reevaluation of his life and legacy, recognizing him as an inspirational progressive thinker, populist hero, and radical influence on the New Deal before an assassin’s bullet ended his life in 1935. First as governor and then as U.S. senator, Long transformed the politics of Louisiana by standing for the interests of citizens whom state officials had historically ignored. He eased suffrage restrictions so that more people could vote, and voters endorsed his program of more robust government services and shifting the tax burden to those better able to pay. In the United States Senate, during the darkest days of the Great Depression, he advocated loudly and ceaselessly for the redistribution of wealth, expanding public works, increasing the money supply, insuring bank deposits, paying old-age pensions and veterans’ benefits, delivering a minimum income for families, and funding college and vocational education. President Franklin D. Roosevelt, along with other politicians and pundits, dismissed Long’s proposals as nonsense put forth by a reckless demagogue in search of votes. Despite several biographies, acclaimed novels, and historical studies in the years since Long’s death, his reputation today is mostly caricature: a spellbinding speaker, a dictator, a populist firebrand who was unprincipled and corrupt. Using previously untapped personal papers of Long and his son Russell, other primary sources, recent scholarship, and his experience as a lawyer, Patterson provides a necessary corrective as he analyzes the contours of Long’s career, deconstructs the elements of his success, undercuts several myths related to his time in office, and explains the circumstances that led to his ultimate downfall. The result is the most comprehensive, balanced, and analytical study of the Kingfish to date.