A mark-recapture population estimate for invasive silver carp (<Emphasis Type="Italic">Hypophthalmichthys molitrix</Emphasis>) in the La Grange Reach,Illinois River

Invasive silver carp (Hypophthalmichthys molitrix) populations have expanded greatly in the Upper Mississippi River System (UMRS) since their introduction in the early 1970s. We conducted a Chapman-modified, continuous Schnabel mark-recapture population and biomass estimate for silver carp (106–901 mm) in the La Grange reach, Illinois River during 2007–2008. We estimated a total of 328,192 (95% CI 231,226–484,474) silver carp (2,544 per river km 1,792–3,756) comprising 705 (95% CI; 496–1,040) metric tons of biomass (5.5 metric tons per river km 3.8–8.1). Long Term Resource Monitoring Program (LTRMP) data from the La Grange reach showed an exponential increase in silver carp catches since 1998, with an intrinsic rate of increase approaching 84%. In 2008, silver carp comprised about 51% of the total LTRMP annual fish collection. To our knowledge, this large river reach may contain the greatest ambient densities of wild silver carp in the world. Our findings provide a target for reduction efforts and also emphasize the importance of the La Grange reach as a source population for potential expansion of the species to the Laurentian Great Lakes.     

Identification of 2chromosome region translocated onto the W chromosome by RFLP with EST-cDNA clones in the Gensei-kouken strains of the mulberry silkworm, Bombyx mori L

In silkworms, sex-limited strains are either obtained spontaneously or induced by X-rays or gamma rays. When a fragment of an autosome carrying a dominant allele of those genes responsible for certain characters is translocated onto a W chromosome, the female of the successive generations will express these phenotypic characters and sex discrimination can be facilitated. Gensei-kouken strains are sex-limited strains of silkworms developed by irradiating the pupae with gamma rays, by which a portion of the second chromosome is translocated onto the W chromosome. In these improved strains, the females are yellow-blooded and spin yellow cocoons. By using the EST-cDNA clones mapped on the Z chromosome, we identified the sex according to the polymorphic banding pattern or intensity of the signals. Furthermore, by using the clones on the second chromosome, the region of the second chromosome translocated onto the W chromosome was also defined. In both the A95 and A 96 strains selected for the present study, only the mid-portion of the second chromosome was translocated. The differences in length of the fragments translocated in these strains are discussed.     

Distance decay of community dynamics in rocky intertidal sessile assemblages evaluated by transition matrix models

It is well known that the similarity in species composition between two communities decays with the geographic distance that separates them. It is thus likely that the similarity in the dynamics of two communities also decays with distance, because the distance–decay relationship is fundamental in nature. However, the distance–decay relationships of community dynamics have not yet been revealed. We used transition matrix models to evaluate distance–decay relationships of seasonal community dynamics (from spring to summer) in rocky intertidal sessile assemblages along the Pacific coast of Japan between 31°N and 43°N. We evaluated the distance–decay relationships of whole-community dynamics and of three dynamics-related components—recruitment, disturbance, and species interaction (competition and facilitation)—for communities separated by distances ranging from several meters to thousands of kilometers. The similarity of the recruitment dynamics among communities declined rapidly with distance within the fine spatial scale, but only moderately within larger scales. The similarity of the disturbance dynamics was independent of distance, and the similarity of species interaction declined slightly with increasing distance. The similarity of whole-community dynamics declined rapidly with distance at a fine spatial scale and moderately at larger scales. The fact that the distance–decay relationship of whole-community dynamics was similar to that of recruitment may suggest that recruitment processes are the most important determinant of spatial variability of community dynamics at our study sites during the study period.     

GAPDH mediates nitrosylation of nuclear proteins

S-nitrosylation of proteins by nitric oxide is a major mode of signalling in cells. S-nitrosylation can mediate the regulation of a range of proteins, including prominent nuclear proteins, such as HDAC2 (ref. 2) and PARP1 (ref. 3). The high reactivity of the nitric oxide group with protein thiols, but the selective nature of nitrosylation within the cell, implies the existence of targeting mechanisms. Specificity of nitric oxide signalling is often achieved by the binding of nitric oxide synthase (NOS) to target proteins, either directly or through scaffolding proteins such as PSD-95 (ref. 5) and CAPON. As the three principal isoforms of NOS--neuronal NOS (nNOS), endothelial NOS (eNOS) and inducible NOS (iNOS)--are primarily non-nuclear, the mechanisms by which nuclear proteins are selectively nitrosylated have been elusive. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is physiologically nitrosylated at its Cys 150 residue. Nitrosylated GAPDH (SNO-GAPDH) binds to Siah1, which possesses a nuclear localization signal, and is transported to the nucleus. Here, we show that SNO-GAPDH physiologically transnitrosylates nuclear proteins, including the deacetylating enzyme sirtuin-1 (SIRT1), histone deacetylase-2 (HDAC2) and DNA-activated protein kinase (DNA-PK). Our findings reveal a novel mechanism for targeted nitrosylation of nuclear proteins and suggest that protein-protein transfer of nitric oxide groups may be a general mechanism in cellular signal transduction.     

The Role of Catalase in Pulmonary Fibrosis

Background

Catalase is preferentially expressed in bronchiolar and alveolar epithelial cells, and acts as an endogenous antioxidant enzyme in normal lungs. We thus postulated epithelial damage would be associated with a functional deficiency of catalase during the development of lung fibrosis.

Methods

The present study evaluates the expression of catalase mRNA and protein in human interstitial pneumonias and in mouse bleomycin-induced lung injury. We examined the degree of bleomycin-induced inflammation and fibrosis in the mice with lowered catalase activity.

Results

In humans, catalase was decreased at the levels of activity, protein content and mRNA expression in fibrotic lungs (n = 12) compared to control lungs (n = 10). Immunohistochemistry revealed a decrease in catalase in bronchiolar epithelium and abnormal re-epithelialization in fibrotic areas. In C57BL/6J mice, catalase activity was suppressed along with downregulation of catalase mRNA in whole lung homogenates after bleomycin administration. In acatalasemic mice, neutrophilic inflammation was prolonged until 14 days, and there was a higher degree of lung fibrosis in association with a higher level of transforming growth factor-β expression and total collagen content following bleomycin treatment compared to wild-type mice.

Conclusions

Taken together, these findings demonstrate diminished catalase expression and activity in human pulmonary fibrosis and suggest the protective role of catalase against bleomycin-induced inflammation and subsequent fibrosis.     

Light and electron microscopy and molecular phylogenetic analyses of Chloromonas pseudoplatyrhyncha (Volvocales,Chlorophyceae)

A strain of Chloromonas pseudoplatyrhyncha (Pascher) P. C. Silva, which has not been studied previously using cultured material, was established from a soil sample collected in Japan and examined by light microscopy, transmission electron microscopy, and molecular phylogenetic analyses. The chloroplasts of this species showed no pyrenoids under light microscopy. However, transmission electron microscopy and the staining methods with carmine after fixation in an acidified hypochlorite solution revealed that Chloromonas pseudoplatyrhyncha actually had multiple, atypical pyrenoids (pyrenoid matrices without associated starch grains) that were angular in shape and distributed in the interior regions of the lobes of the chloroplasts. Although some other species of Chloromonas have atypical pyrenoids in the chloroplast, such angular pyrenoids have not previously been reported within the Volvocales. The present molecular phylogenetic analysis, based on 18S ribosomal RNA, adenosine triphosphate synthase β‐subunit, and P700 chlorophyll a‐apoprotein A2 gene sequences, demonstrated that Chloromonas pseudoplatyrhyncha belonged to the Chloromonas lineage or Chloromonadinia, in which it occupied a basal position outside a robust, large monophyletic group consisting of 13 species of Chloromonas and Gloeomonas.     

Nucleomorph genome diversity and its phylogenetic implications in cryptomonad algae

The relationship between phylogeny and nucleomorph genome size was examined in 16 strains of cryptomonad algae using pulsed‐field gel electrophoresis, Southern hybridization and phylogenetic analyses. Our results suggest that all cryptomonads examined in this study contain three nucleomorph chromosomes and their total genome size ranges from 495 to 750 kb. In addition, we estimated the plastid genome size of the respective organisms. The plastid genomes of photosynthetic strains were approximately 120–160 kb in size, whereas the non‐photosynthetic Cryptomonas paramecium NIES715 possesses a genome of approximately 70 kb. Phylogenetic analysis of the nuclear small subunit ribosomal DNA (SSU rDNA) gene showed that nucleomorph genome size varies considerably within closely related strains. This result indicates that the reduction of nucleomorph genomes is a rapid phenomenon that occurred multiple times independently during cryptomonad evolution. The nucleomorph genome sizes of Cryptomonas rostratiformis NIES277 appeared to be approximately 495 kb. This is smaller than that of Guillardia theta CCMP327, which until now was thought to have the smallest known nucleomorph genome size among photosynthetic cryptomonads.     

Rapid demonstration of diversity of sulfatide molecular species from biological materials by MALDI-TOF MS

By combining the partition method for enrichment of sulfatides without any chromatographic procedures and the preparation method of lysosulfatides, we succeeded in analyzing these sulfated glycosphingolipids from biological materials by matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-TOF MS) to reduce the complexity of mass fragmentation patterns within a day. We found that sulfated GalCer (HSO3-3Gal beta 1Cer) (SM4s [galactosylsulfatide]) was composed of different species. While composition of SM4s specifically depended on source materials, it always contained hydroxy fatty acids of various degrees. In addition to the common sphingoid 4-sphingenine (d18:1), uncommon/unusual sphingoids phytosphingosine (4-hydroxysphinganine) (t18:0), eicosasphinganine (d20:0), 4-eicosasphingenine (d20:1), and sphingadienine (d18:2) were easily detected. Finally, in addition to SM4s, sulfatide sulfated LacCer (HSO3-3Gal beta 4Glc beta 1Cer) (SM3 [sulfated lactosylceramide]) and sulfated Gg3Cer (GalNAc beta 4(HSO3-3)Gal beta 4Glc beta 1Cer) (SM2 [sulfated gangliotriaosylceramide]) were clearly detected in renal tubule cells. The major SM4s was composed of ceramides possessing d18:1 with C22 hydroxy fatty acids (C22:0 h), C23:0 h, and C24:0 h, whereas the major SM3/SM2 were composed of ceramides possessing t18:0 with C22 normal fatty acids (C22:0), C23:0, C24:0. Namely, in these two series of sulfatides, either fatty acids or sphingoids were hydroxylated, and chain lengths of these components were exactly the same, consequently resulting in a similar polarity of ceramide moieties in these sulfatide species. These results demonstrated diversities of sulfatide molecular species, not only with respect to sugar moieties but also to ceramide moieties, which are probably important for specific effective functions in particular microenvironments such as lipid membrane microdomains.