A series of 5-(5,6)-dihydrouracil substituted 8-hydroxy-[1,6]naphthyridine-7-carboxylic acid 4-fluorobenzylamide inhibitors of HIV-1 integrase and viral replication in cells

Introduction of a 5,6-dihydrouracil functionality in the 5-position of N-(4-fluorobenzyl)-8-hydroxy-[1,6]naphthyridine-7-carboxamide 1 led to a series of highly active HIV-1 integrase inhibitors. These compounds displayed low nanomolar activity in inhibiting both the strand transfer process of HIV-1 integrase and viral replication in cells. Compound 11 is a 150-fold more potent antiviral agent than 1, with a CIC(95) of 40 nM in the presence of human serum. It displays good pharmacokinetics when dosed in rats and dogs.     

Cdc123 and checkpoint forkhead associated with RING proteins control the cell cycle by controlling eIF2gamma abundance

Eukaryotic initiation factor 2 (eIF2) is a central regulator of translational initiation in times of growth and times of stress. Here we discovered three new conserved regulators of eIF2 in Saccharomyces cerevisiae. cdc123, homolog of mammalian D123, is a new cell division cycle mutant with a G2 delay at permissive temperature and a terminal, mating-proficient G1 arrest point. Cdc123 protein is regulated by nutrient availability. CHF1 and CHF2, homologs of mammalian checkpoint forkhead associated with RING genes, are required for G2 delay and G1 arrest of cdc123-4 and promote G1 delay when over-expressed. Cell cycle delaying activity and the natural instability of Chf1 and Chf2 depend on the integrity of both domains and association with Cdc123. Genetic analysis maps the Chf1 forkhead associated domain-binding site to the conserved Thr-274 of Cdc123, suggesting that mammalian D123 is a key target of Chfr. Gcd11, the gamma subunit of eIF2, is an additional Cdc123-interacting protein that is an essential target of the Cdc123 cell cycle promoting and Chf cell cycle arresting activity whose abundance is regulated by Cdc123, Chf1, and Chf2. Loss of cdc123 activity promotes Chf1 and Chf2 accumulation and Gcd11 depletion, accounting for the essentiality of Cdc123. The data establish the Cdc123-Chf-Gcd11 axis as an essential pathway for nutritional control of START that runs parallel to the Tor-Gcn2-Sui2 system of translational control.     

MicroRNAs: expression, avoidance and subversion by vertebrate viruses

MicroRNAs (miRNAs), which can be expressed in a cell-type and tissue-specific manner, can influence the activities of genes that control cell growth and differentiation. Viruses often have clear tissue tropisms, raising the possibility that cellular miRNAs might modulate their pathogenesis. In this Review, we discuss recent findings that some vertebrate viruses either encode miRNAs or subvert cellular miRNAs, and that these miRNAs participate in both the infectious and the latent phase of the viral life cycle.     

The cell biology of touch

The sense of touch detects forces that bombard the body's surface. In metazoans, an assortment of morphologically and functionally distinct mechanosensory cell types are tuned to selectively respond to diverse mechanical stimuli, such as vibration, stretch, and pressure. A comparative evolutionary approach across mechanosensory cell types and genetically tractable species is beginning to uncover the cellular logic of touch reception.     

Neoascarophis macrouri n. sp. (Nematoda: Cystidicolidae) from the stomach of Macrourus berglax (Macrouridae) in the eastern Greenland Sea

A new species of parasitic nematode, Neoascarophis macrouri n. sp. (Cystidicolidae), is described from the stomach and stomach wall of the marine deep-water fish Macrourus berglax (onion-eye grenadier) in the eastern Greenland Sea (North Atlantic Ocean). The new species, studied using both light and scanning electron microscopy, is characterised mainly by the location of the vulva near the posterior end of the body (a short distance anterior to the anus), non-filamented eggs, the structure of the mouth, a short vestibule and the length of the spicules (567-615 and 144-156 mum). Metabronema insulanum Solov'eva, 1991 is transferred to Neoascarophis as N. insulana (Solov'eva, 1991) n. comb.     

Neoascarophis macrouri n. sp. (Nematoda: Cystidicolidae) from the stomach of Macrourus berglax (Macrouridae) in the eastern Greenland Sea

A new species of parasitic nematode, Neoascarophis macrouri n. sp. (Cystidicolidae), is described from the stomach and stomach wall of the marine deep-water fish Macrourus berglax (onion-eye grenadier) in the eastern Greenland Sea (North Atlantic Ocean). The new species, studied using both light and scanning electron microscopy, is characterised mainly by the location of the vulva near the posterior end of the body (a short distance anterior to the anus), non-filamented eggs, the structure of the mouth, a short vestibule and the length of the spicules (567–615 and 144–156 μm). Metabronema insulanum Solov’eva, 1991 is transferred to Neoascarophis as N. insulana (Solov’eva, 1991) n. comb.     

A novel gammaherpesvirus associated with genital lesions in a Blainville's beaked whale (Mesoplodon densirostris)

An adult male Blainville's beaked whale (Mesoplodon densirostris) was found stranded on the Atlantic coast of the USA on 28 January 2004. Necropsy revealed a focal papilloma-like penile lesion, the cells from which revealed single 4-6 microm basophilic intranuclear inclusions. Total DNA extracted from lesion material was tested using a pan-herpes-virus PCR assay that targets the DNA polymerase gene and found to be positive. When the amplified DNA fragment was cloned, sequenced, and compared to GenBank-deposited herpesvirus DNA polymerase sequences, the detected virus was determined to be a distinct member of the Gammaherpesvirinae subfamily of herpesviruses. This new virus, tentatively named Ziphiid herpesvirus type 1, was associated with but not determined to be the cause of genital disease in the Blainville's beaked whale.     

Inactivation of single-celled Ascaris suum eggs by low-pressure UV radiation

Intact and decorticated single-celled Ascaris suum eggs were exposed to UV radiation from low-pressure, germicidal lamps at fluences (doses) ranging from 0 to 8,000 J/m2 for intact eggs and from 0 to 500 J/m2 for decorticated eggs. With a UV fluence of 500 J/m2, 0.44-+/-0.20-log inactivation (mean+/-95% confidence interval) (63.7%) of intact eggs was observed, while a fluence of 4,000 J/m2 resulted in 2.23-+/-0.49-log inactivation (99.4%). (The maximum quantifiable inactivation was 2.5 log units.) Thus, according to the methods used here, Ascaris eggs are the most UV-resistant water-related pathogen identified to date. For the range of fluences recommended for disinfecting drinking water and wastewater (200 to 2,000 J/m2), from 0- to 1.5-log inactivation can be expected, although at typical fluences (less than 1,000 J/m2), the inactivation may be less than 1 log. When the eggs were decorticated (the outer egg shell layers were removed with sodium hypochlorite, leaving only the lipoprotein ascaroside layer) before exposure to UV, 1.80-+/-0.32-log reduction (98.4%) was achieved with a fluence of 500 J/m2, suggesting that the outer eggshell layers protected A. suum eggs from inactivation by UV radiation. This protection may have been due to UV absorption by proteins in the outer layers of the 3- to 4-microm-thick eggshell. Stirring alone (without UV exposure) also inactivated some of the Ascaris eggs (approximately 20% after 75 min), which complicated determination of the inactivation caused by UV radiation alone.     

SER-7, a Caenorhabditis elegans 5-HT7-like receptor, is essential for the 5-HT stimulation of pharyngeal pumping and egg laying

Serotonin (5-HT) stimulates both pharyngeal pumping and egg laying in Caenorhabditis elegans. Four distinct 5-HT receptors have been partially characterized, but little is known about their function in vivo. SER-7 exhibits most sequence identity to the mammalian 5-HT7 receptors and couples to a stimulation of adenyl cyclase when expressed in COS-7 cells. However, many 5-HT7-specific agonists have low affinity for SER-7. 5-HT fails to stimulate pharyngeal pumping and the firing of the MC motorneurons in animals containing the putative ser-7(tm1325) and ser-7(tm1728) null alleles. In addition, although pumping on bacteria is upregulated in ser-7(tm1325) animals, pumping is more irregular. A similar failure to maintain "fast pumping" on bacteria also was observed in ser-1(ok345) and tph-1(mg280) animals that contain putative null alleles of a 5-HT2-like receptor and tryptophan hydroxylase, respectively, suggesting that serotonergic signaling, although not essential for the upregulation of pumping on bacteria, "fine tunes" the process. 5-HT also fails to stimulate egg laying in ser-7(tm1325), ser-1(ok345), and ser-7(tm1325) ser-1(ok345) animals, but only the ser-7 ser-1 double mutants exhibit an Egl phenotype. All of the SER-7 mutant phenotypes are rescued by the expression of full-length ser-7gfp translational fusions. ser-7gfp is expressed in several pharyngeal neurons, including the MC, M2, M3, M4, and M5, and in vulval muscle. Interestingly, 5-HT inhibits egg laying and pharyngeal pumping in ser-7 null mutants and the 5-HT inhibition of egg laying, but not pumping, is abolished in ser-7(tm1325);ser-4(ok512) double mutants. Taken together, these results suggest that SER-7 is essential for the 5-HT stimulation of both egg laying and pharyngeal pumping, but that other signaling pathways can probably fulfill similar roles in vivo.