A novel protein-conjugating system for Ufm1, a ubiquitin-fold modifier

Several studies have addressed the importance of various ubiquitin-like (UBL) post-translational modifiers. These UBLs are covalently linked to most, if not all, target protein(s) through an enzymatic cascade analogous to ubiquitylation, consisting of E1 (activating), E2 (conjugating), and E3 (ligating) enzymes. In this report, we describe the identification of a novel ubiquitin-fold modifier 1 (Ufm1) with a molecular mass of 9.1 kDa, displaying apparently similar tertiary structure, although lacking obvious sequence identity, to ubiquitin. Ufm1 is first cleaved at the C-terminus to expose its conserved Gly residue. This Gly residue is essential for its subsequent conjugating reactions. The C-terminally processed Ufm1 is activated by a novel E1-like enzyme, Uba5, by forming a high-energy thioester bond. Activated Ufm1 is then transferred to its cognate E2-like enzyme, Ufc1, in a similar thioester linkage. Ufm1 forms several complexes in HEK293 cells and mouse tissues, revealing that it conjugates to the target proteins. Ufm1, Uba5, and Ufc1 are all conserved in metazoa and plants but not in yeast, suggesting its potential roles in various multicellular organisms.     

Is pulse transit time useful in differentiating respiratory events for patients with a sleep breathing disorder? A pilot study

Variation of inspiratory effort in sleep disordered breathing induces the oscillation in blood pressure, which corresponds inversely to pulse transit time (PTT). This study evaluated the feasibility of PTT as a visual parameter for differentiating respiratory events in patients with a sleep breathing disorder. Sixteen patients who complained of snoring and sleep apnea were booked into the study. Polysomnographic data of Zopiclone induced daytime sleep were analyzed, PTT and intraesophageal pressure (Peso) were assessed for each respiratory event. With respect to Peso, the total accuracy of PTT was 51.8% for 1266 events. The relatively high coincidence rate could be observed in obstructive events (57.1%), with crescendo Peso pattern (71.5%), in lateral position (82.2%). Pulse transit time oscillation could only partly reflect respiratory rhythm to some degree (56.5%). Absolute PTT value presented a poor relationship with respiratory effort. Pulse transit time coincided well with crescendo Peso in lateral position for obstructive events. Swings in PTT could only partly fit respiratory wave data. Absolute PTT value and its change could not reflect respiratory effort. Although PTT is a non-invasive and convenient way for assessing inspiratory effort, its variable sensitivity to different events, respiratory patterns, positions, different patients and other situations, limit its feasibility. Further work is required.

     

Starch phosphorus content in potato (Solanum tuberosum L.) cultivars and its effect on other starch properties

The research presented herein provides valuable data with respect to the phosphorus content of starches from many potato (Solanum tuberosum L.) cultivars using an energy-dispersive X-ray fluorescence technique. In all starches examined, the phosphorus content ranged from 308 to 1244 ppm. Furthermore, the estimation of the starch characteristics of representative samples differing manifestly in their phosphorus content indicated that enhancing the starch phosphate resulted in significant increases in the swelling power, peak viscosity, and breakdown and significant but small increases in the onset and peak temperatures of gelatinization. Other starch quality parameters, such as the amylose content, median granule size, and the gelatinization enthalpy, did not change significantly due to the degree of phosphate substitution of starch.     

Tidal and diurnal variations in larval fish abundance in an estuarine inlet in Ariake Bay,Japan: implication for selective tidal stream transport

We have conducted a preliminary study of tidal and diurnal variations in the distribution of dominant larval and juvenile fishes in the Chikugo River inlet (Ariake Bay, Kyushu, Japan) to determine whether selective tidal stream transport (STST) occurs. Larval and juvenile fish were collected from the mesohaline zone of the Chikugo River inlet during spring 2002. Temperature, salinity, depth, and current velocity were measured. Larval and juvenile abundance were compared among four tidal conditions, flooding tide, high tide, ebbing tide, and low tide, and between day and night. A total of 12 families, 15 species, and 5,577 individuals were collected. Temperature did not vary significantly with tidal conditions whereas salinity, depth, and current velocity varied significantly. Salinity also was correlated significantly and positively with depth. The abundance of most of the fishes was correlated positively and significantly with salinity and depth. Lateolabrax japonicus, Trachidermus fasciatus, Acanthogobius hasta, and other gobiid larvae (Gobiidae spp.) were significantly more abundant during high tide; in contrast, Coilia nasus and Neosalanx reganius were most abundant during low tide. The abundance of most of the fishes was higher during high tides at night than during the day, indicating the existence of STST, which may be strategically associated with ascending progress to upstream nursery areas.     

Development of an efficient method for screening microorganisms by using symbiotic association between <Emphasis Type="Italic">Nasutitermes takasagoensis</Emphasis> and intestinal microorganisms

Screening method of microorganisms that utilized the symbiotic association between insect (Nasutitermes takasagoensis: Nt) and intestinal microorganisms was developed. The existence of desired microorganisms that grew by degrading difficult-to-degrade materials in the gut was detected using survivability of Nt as an indicator. The desired microorganisms were isolated from the survived Nt. It was thought that guts of Nt behave as continuous culture systems whereby microorganisms that cannot degrade diet components are washed out, whereas those that can degrade it are retained and concentrated in the gut. About 60% of Nt fed with phenol artificial diet (PAD) died within 7 days, while 4% of termites survived for 9 days. The structure of intestinal microorganisms of the survived Nt fed with PAD differed from the bacterial communities obtained from enrichment culture (which contained phenol) of wood-feeding Nt. Relatively high colonies (650-times) were detected in the gut of Nt fed on phenol artificial diet compared with those obtained when Nt was fed on wood. Seven denaturing gradient gel electrophoresis (DGGE) bands were detected from gut of wood-feeding Nt, whereas 11 DGGE-bands were detected from that of phenol-feeding Nt. Out of 11 DGGE-bands, 5 of them were sequenced, and bacterial species including phenol-degrading bacteria were identified.     

A neural-specific F-box protein Fbs1 functions as a chaperone suppressing glycoprotein aggregation

Fbs1 is an F-box protein present abundantly in the nervous system. Similar to the ubiquitously expressed Fbs2, Fbs1 recognizes N-glycans at the innermost position as a signal for unfolded glycoproteins, probably in the endoplasmic reticulum-associated degradation pathway. Here, we show that the in vivo majority of Fbs1 is present as Fbs1-Skp1 heterodimers or Fbs1 monomers but not SCF(Fbs1) complex. The inefficient SCF complex formation of Fbs1 and the restricted presence of SCF(Fbs1) bound on the endoplasmic reticulum membrane were due to the short linker sequence between the F-box domain and the sugar-binding domain. In vitro, Fbs1 prevented the aggregation of the glycoprotein through the N-terminal unique sequence of Fbs1. Our results suggest that Fbs1 assists clearance of aberrant glycoproteins in neuronal cells by suppressing aggregates formation, independent of ubiquitin ligase activity, and thus functions as a unique chaperone for those proteins.     

Dietary habits of the fanray Platyrhina tangi (Batoidea: Platyrhinidae) in Ariake Bay, Japan

The dietary habits of the fanray Platyrhina tangi were investigated by analyzing the stomach contents of specimens collected in Ariake Bay, Japan. Of 334 stomach specimens, 324 contained food and 10 (3.0%) were empty. The mean percentage weight of stomach contents per unit of body weight was 0.59%. Thirty-seven taxonomic levels of prey were identified. The most common prey was shrimp, followed by fish and mysids. There were no differences in the composition of the diet between sexes, but an ontogenetic dietary shift was observed. Shrimps were the most common prey in all size classes. In addition, smaller individuals frequently ate mysids, and larger individuals often consumed fish. Dietary breadth values increased with size. Trophic level analysis revealed that trophic level increased with size; however, this species is consistently a secondary consumer. Dental sexual dimorphism was also observed. Specifically, mature males had much longer and sharper cusps than females and immature males. Since males and females had similar diets, dental sexual dimorphism may be related to their reproductive behaviour.     

Targeting Interleukin-6: All the Way to Treat Autoimmune and Inflammatory Diseases

Interleukin (IL)-6, a cytokine featuring redundancy and pleiotropic activity, contributes to host defense against acute environmental stress, while dysregulated persistent IL-6 production has been demonstrated to play a pathological role in various autoimmune and chronic inflammatory diseases. Targeting IL-6 is thus a rational approach to the treatment of these diseases. Indeed, clinical trials of tocilizumab, a humanized anti-IL-6 receptor antibody have verified its efficacy and tolerable safety for patients with rheumatoid arthritis, Castleman''s disease and systemic juvenile idiopathic arthritis, resulting in approval of this innovative biologic for treatment of these diseases. Moreover, a considerable number of case reports and pilot studies of off-label use of tocilizumab point to the beneficial effects of tocilizumab for a variety of other phenotypically different autoimmune and chronic inflammatory diseases. Elucidation of the source of IL-6 and of mechanisms through which IL-6 production is dysregulated can thus be expected to lead to clarification of the pathogenesis of various diseases.     

Occurrence of 5SrRNA in high molecular weight complexes of aminoacyl-tRNA synthetases in a rat liver supernatant.

The 5SrRNA in the rat liver postmicrosomal supernatant was investigated. Acrylamide gel electrophoresis and Northern blot analysis showed that most of the 5SrRNA was present in the fractions obtained on high molecular weight regions separated by Sephadex G-200 column chromatography of the supernatant, which contained the bulk of the methionyl-tRNA synthetase (Fraction I) and tyrosyl-tRNA synthetase (Fraction II). A high molecular weight complex containing nine aminoacyl-tRNA synthetases [Mirande, M., LeCorre, D., & Waller, J.-P. (1985) Eur. J. Biochem. 147, 281-289] was purified by fractional precipitation with polyethylene glycol 6000, gel filtration on Bio-Gel A-1.5m, and finally tRNA-Sepharose column chromatography, which gave two fractions. Fraction B showed the activities of nine aminoacyl-tRNA synthetases and gave protein bands corresponding to eight previously identified enzymes on SDS-PAGE. Fraction A, eluted with a lower KCl concentration than Fraction B, showed lower activities than fraction B of eight of the aminoacyl-tRNA synthetases, the exception being prolyl-tRNA synthetase. The staining patterns with ethidium bromide of the RNAs after PAGE showed 5SrRNA bands for Fraction A but not for Fraction B. However, Northern blot analysis indicated that 5SrRNA was present in both Fractions A and B. The staining pattern after SDS-PAGE of Fraction A with Coomassie Brilliant Blue showed several protein bands in addition to those observed for Fraction B, one of which, with a staining intensity comparable with those of other bands, was located at the same position as ribosomal protein L5, which is the protein moiety of the 5SrRNA-L5 protein complex of ribosomal 60S subunits.(ABSTRACT TRUNCATED AT 250 WORDS)