Characterization of the interaction between the Wilson and Menkes disease proteins and the cytoplasmic copper chaperone, HAH1p.

Wilson disease (WD) and Menkes disease (MNK) are inherited disorders of copper metabolism. The genes that mutate to give rise to these disorders encode highly homologous copper transporting ATPases. We use yeast and mammalian two-hybrid systems, along with an in vitro assay to demonstrate a specific, copper-dependent interaction between the six metal-binding domains of the WD and MNK ATPases and the cytoplasmic copper chaperone HAH1. We demonstrate that several metal-binding domains interact independently or in combination with HAH1p, although notably domains five and six of WDp do not. Alteration of either the Met or Thr residue of the HAH1p MTCXXC motif has no observable effect on the copper-dependent interaction, whereas alteration of either of the two Cys residues abolishes the interaction. Mutation of any one of the HAH1p C-terminal Lys residues (Lys(56), Lys(57), or Lys(60)) to Gly does not affect the interaction, although deletion of the 15 C-terminal residues abolishes the interaction. We show that apo-HAH1p can bind in vitro to copper-loaded WDp, suggesting reversibility of copper transfer from HAH1p to WD/MNKp. The in vitro HAH1/WDp interaction is metalospecific; HAH1 preincubated with Cu(2+) or Hg(+) but not with Zn(2+), Cd(2+), Co(2+), Ni(3+), Fe(3+), or Cr(3+) interacted with WDp. Finally, we model the protein-protein interaction and present a theoretical representation of the HAH1p.Cu.WD/MNKp complex.     

Pattern of Resource Allocation of Six Plantago Species with Different Breeding Systems

Plantago exhibit great deal of differences in the breeding system. The reproductive effort calculated on the basis of, (i) dry biomass of foliar and floral parts and (ii) seed output-weight (mg) per unit leaf area (cm²), exhibits relation with breeding system. The predominantly inbreeding taxa invest higher reproductive effort compared to their outbreeding allies. In terms of sex allocation strategies, the outbreeding species like P. lanceolata, P. lagopus invest more to the development of floral features and to male functions. On the contrary, inbreeding species such as P. patagonica, P. drummondii, and P. ovata invest greater resources to the female function. Received 13 April 1998/ Accepted in revised form 6 November 1998     

Airborne Pollen Grains of Gurdur,Turkey

Ｔｈｃ ｐｏｌｌｅｎ ｇｒａｉｎｓ ｉｎ ｔｈｅ ａｔｍｏｓｐｈｅｒｅ ｏｆ Ｂｕｒｄｕｒ ｈａｖｅ ｂｅｅｎ ｓｔｕｄｉｅｄ ｆｏｒ ａ ｔｗｏ－ｙｅａｒ ｐｅｒｉｏｄ（１９９６ｔｈｒｏｕｇｈ １９９７）ｗｉｔｈ ａ Ｄｕｒｈａｍ ｓａｍｐｌｅｒ．Ａ ｔｏｔａｌ ｏｆ １１ ８８１ ｐｏｌｌｅｎ ｇｒａｉｎｓ ｂｅｌｏｎｇｉｎｓ ｔｏ ３９ ｔａｘａ ｈａｖｅ ｂｅｅｎ ｉｄｅｎｔｉ－ｆｉｅｄ     

A blocking factor in normal animal sera inhibiting immunologic reactions in vitro]

An extremely thermostable and resistant to some chemical substances factor was found in the sera of Wistar and noninbred rats of different age, male and female. This factor inhibited the action of normal and immune antibodies to rat erythrocytes and rat serum antigens. The blocking factor was relatively specific and more effective in respect to the normal antibodies than to the immune ones. The activity of the blocking factor was connected with the alpha1-globulin.     

Genome-scale analysis of DNA methylation in colorectal cancer using Infinium HumanMethylation450 BeadChips

Illumina’s Infinium HumanMethylation450 BeadChip arrays were used to examine genome-wide DNA methylation profiles in 22 sample pairs from colorectal cancer (CRC) and adjacent tissues and 19 colon tissue samples from cancer-free donors. We show that the methylation profiles of tumors and healthy tissue samples can be clearly distinguished from one another and that the main source of methylation variability is associated with disease status. We used different statistical approaches to evaluate the methylation data. In general, at the CpG-site level, we found that common CRC-specific methylation patterns consist of at least 15,667 CpG sites that were significantly different from either adjacent healthy tissue or tissue from cancer-free subjects. Of these sites, 10,342 were hypermethylated in CRC, and 5,325 were hypomethylated. Hypermethylated sites were common in the maximum number of sample pairs and were mostly located in CpG islands, where they were significantly enriched for differentially methylated regions known to be cancer-specific. In contrast, hypomethylated sites were mostly located in CpG shores and were generally sample-specific. Despite the considerable variability in methylation data, we selected a panel of 14 highly robust candidates showing methylation marks in genes SND1, ADHFE1, OPLAH, TLX2, C1orf70, ZFP64, NR5A2, and COL4A. This set was successfully cross-validated using methylation data from 209 CRC samples and 38 healthy tissue samples from The Cancer Genome Atlas consortium (AUC = 0.981 [95% CI: 0.9677–0.9939], sensitivity = 100% and specificity = 82%). In summary, this study reports a large number of loci with novel differential methylation statuses, some of which may serve as candidate markers for diagnostic purposes.     

Optical Coherence Tomography for live imaging of mammalian development

Understanding the nature and mechanism of congenital defects of the different organ systems in humans has heavily relied on the analysis of the corresponding mutant phenotypes in rodent models. Optical Coherence Tomography (OCT) has recently emerged as a powerful tool to study early embryonic development. This non-invasive optical methodology does not require labeling and allows visualization of embryonic tissues with single cell resolution. Here, we will discuss how OCT can be applied for structural imaging of early mouse and rat embryos in static culture, cardiodynamic and blood flow analysis, and in utero embryonic imaging at later stages of gestation, demonstrating how OCT can be used to assess structural and functional birth defects in mammalian models.     

Analysis of extrachromosomal structures containing human centromeric alphoid satellite DNA sequences in mouse cells

Yeast artificial chromosomes (YACs) spanning the centromeric region of the human Y chromosome were introduced into mouse LA-9 cells by spheroplast fusion in order to determine whether they would form mammalian artificial chromosomes. In about 50% of the cell lines generated, the YAC DNA was associated with circular extrachromosomal structures. These episomes were only present in a proportion of the cells, usually at high copy number, and were lost rapidly in the absence of selection. These observations suggest that, despite the presence of centromeric sequences, the structures were not segregating efficiently and thus were not forming artificial chromosomes. However, extrachromosomal structures containing alphoid DNA appeared cytogenetically smaller than those lacking it, as long as yeast DNA was also absent. This suggests that alphoid DNA can generate the condensed chromatin structure at the centromere. Edited by: H. F. Willard     

Possible influences of a macroalgal bloom in eelgrass beds on fish assemblages in the lower Knysna Estuary,South Africa

The occurrence of a macroalgal bloom at eelgrass (Zostera capensis) sampling sites in the summer of 2014/2015 provided an opportunity to use underwater video cameras to monitor the possible effects of environmental change on fish diversity and abundance in the lower reaches of the Knysna Estuary. A General Linear Model (GLM) showed that there was a significant difference in the abundance of fish before and after an invasion of the sampling sites by the macroalga Ulva lactuca. The eelgrass bed fish abundance was more affected by the macroalgal bloom than the bare substratum fish abundance, with the Ulva impacting negatively on the relative abundance of Mugilidae in the former habitat. The hypothesis that macroalgal invasions have a negative effect on fish diversity and abundance is therefore supported by this preliminary study.     

Novel markers of gene methylation and expression in breast cancer

An optimized methylation-sensitive restriction fingerprinting technique was used to search for differentially methylated CpG islands in the tumor genome and detected seven genes subject to abnormal epigenetic regulation in breast cancer: SEMA6B, BIN1, VCPIP1, LAMC3, KCNH2, CACNG4, and PSMF1. For each gene, the rate of promoter methylation and changes in expression were estimated in tumor and morphologically intact paired specimens of breast tissue (N = 100). Significant methylation rates of 38, 18, and 8% were found for SEMA6B, BIN1, and LAMC3, respectively. The genes were not methylated in morphologically intact breast tissue. The expression of SEMA6B, BIN1, VCPIP1, LAMC3, KCNH2, CACNG4, and PSMF1 was decreased in 44–94% of tumor specimens by the real-time RT-PCR assay. The most profound changes in SEMA6B and LAMC3 suggest that these genes can be included in biomarker panels for breast cancer diagnosis. Fine methylation mapping of the most frequently methylated CpG islands (SEMA6B, BIN1, and LAMC3) provides a fundamental basis for developing efficient methylation tests for these genes.