Need for flagella for complete virulence of Pseudomonas syringae pv. tabaci: genetic analysis with flagella-defective mutants ?fliC and ?fliD in host tobacco plants

The flagellins purified from Pseudomonas syringae pv. tabaci induce a hypersensitive reaction in nonhost tomato cells. To investigate the role of flagella and flagellin in the compatible interaction, we generated two types of flagella-defective mutant. The fliC mutant lost the fliC gene that encodes flagellin protein, whereas the fliD mutant lost the fliD gene that encodes HAP2-capping protein. The two mutants had markedly reduced ability to cause disease symptoms in tobacco leaves. Furthermore, propagation of the mutants in tobacco leaves was less than that in wild-type pv. tabaci. Compared to the inoculation with wild-type pv. tabaci, inoculation with the two mutants did not markedly induce the expression of typical defense response-related genes such as PAL and hsr203J. Complementation of each fliC and fliD gene to the corresponding deficient mutant restored motility and virulence. These results indicate that flagella of P. syringae pv. tabaci are indispensable organelles for complete virulence on host tobacco plants.     

Application of a PCR-Based Cytoplasm Genotyping Method for Phylogenetic Analysis in Potato

We previously developed five polymerase chain reaction-based markers (T, S, SAC, D, and A) to distinguish potato cytoplasms into six types (M, P, A, W, T, and D). As the applicability of this genotyping method for phylogenetic studies had been questioned, we applied this method to species distantly related to cultivars (four accessions of two tomato species, and 176 accessions of 29 Solanum species). The T marker uncovered two insertions, which, along with a unique S marker band, supported independency of series Piurana. The A and D markers generated unique bands to A- and D-type cytoplasms, respectively, but the SAC marker generated a similar banding pattern to the cytoplasms of both cultivated and their distantly related species. Consequently, while the cytoplasm type definition is validated only among cultivated potatoes and their closely related wild species, the developed markers, with the exception of the SAC marker, could provide useful phylogenetic information.     

Reciprocal differences in DNA sequence and methylation status of the pollen DNA between F<Subscript>1</Subscript> hybrids of <Emphasis Type="Italic">Solanum tuberosum</Emphasis> × <Emphasis Type="Italic">S. demissum</Emphasis>

Reciprocal differences, mostly caused by cytoplasmic effects, are frequently observed in interspecific hybrids. Previously, we found that crosses onto Solanum demissum were much successful with the pollen of interspecific hybrids between S. tuberosum as female and S. demissum as male (TD hybrids) than the reciprocal ones (DT hybrids). To elucidate this reciprocally different crossability, we analyzed the pollen DNA of TD and DT using methylation-sensitive amplified polymorphism (MSAP) analysis. Using 126 primer combinations, MSAP analysis revealed 57 different bands between bulked pollen DNA samples of TD and DT. Individual examination of 16 TD and 9 DT plants disclosed eight bands uniformly different between TD and DT. Their sequencing results revealed two pairs of bands to be identical to each other, resulting in six distinct sequences. As expected, one band shared high homology with chloroplast DNA, and another one with mitochondrial DNA. However, one band that was apparently different at DNA sequence level and maternally transmitted from S. demissum, showed no homology with any known sequence. The remaining three bands were of DNA methylation level differences with no or uncertain homology to known sequences. To our knowledge, this is the first report detecting reciprocal differences in DNA sequence or DNA methylation other than those in cytoplasmic DNA.     

Human hair growth deficiency is linked to a genetic defect in the phospholipase gene LIPH

The molecular mechanisms controlling human hair growth and scalp hair loss are poorly understood. By screening about 350,000 individuals in two populations from the Volga-Ural region of Russia, we identified a gene mutation in families who show an inherited form of hair loss and a hair growth defect. Affected individuals were homozygous for a deletion in the LIPH gene on chromosome 3q27, caused by short interspersed nuclear element-retrotransposon-mediated recombination. The LIPH gene is expressed in hair follicles and encodes a phospholipase called lipase H (alternatively known as membrane-associated phosphatidic acid-selective phospholipase A1alpha), an enzyme that regulates the production of bioactive lipids. These results suggest that lipase H participates in hair growth and development.     

Immunological responses following experimental endobronchial infection of badgers (Meles meles) with different doses of Mycobacterium bovis

The Eurasian badger (Meles meles) is a wildlife reservoir for Mycobacterium bovis infection in Ireland and Great Britain and has been implicated in the transmission of tuberculosis to cattle. Vaccination of badgers is an option that could be used as part of a strategy to control the disease. In this study we used an endobronchial infection procedure to inoculate groups of badgers with three different doses (3x10(3), 2x10(2) and <10 Colony Forming Units (CFUs)) of M. bovis. After 17 weeks the disease status of each animal was determined by post-mortem pathology and culture for M. bovis. Each of the inoculum doses resulted in establishment of infection in the badgers. The cell-mediated immune (CMI) responses were measured by lymphocyte transformation assay (LTA) of peripheral blood mononuclear cells (PBMCs) cultured with bovine tuberculin (PPD-B). In each infected group the CMI responses increased with a kinetic profile corresponding to the delivered dose and the post-mortem pathology. The serological responses were measured by ELISA and a multi-antigen print immunoassay (MAPIA) in order to investigate any changes in the antigenic repertoire associated with different infective doses. In contrast to the CMI responses, the ELISA and MAPIA showed that the recognition of antigens by the badgers was intermittent and not strongly influenced by the dose of M. bovis.     

A System for Identification of Potato Varieties Using SNP Dosage

As in autoteraploids, five genotypes are possible in a biallelic locus, allele dosage could be useful for variety identification in potato. DNA sequences of 13 genes associated with tuber yield, tuber starch content or late blight resistance were surveyed for single nucleotide polymorphism (SNP) in eight tetraploid varieties. A total of 193 potential SNPs was found by Sanger-sequencing, of which 58 were measured for nucleotide frequencies using a pyrosequencer. Of the 58 SNPs, 35 yielded distinct clusters, corresponding to allele dosages. Among these, six were highly correlated with another, leaving 29 independent SNP loci for use in variety discrimination. By using dosage scores at the 29 SNP loci, it was possible to differentiate 115 varieties, except for a sport with red tuber skin color, with at least three different SNP dosages. Therefore, using SNP dosages is a simple, fast and reliable tool for variety identification.     

Adiposity, education and weight loss effort are independently associated with energy reporting quality in the Ontario Food Survey

OBJECTIVES: To examine the associations of adiposity, dietary restraint and other personal characteristics with energy reporting quality. DESIGN/SUBJECTS: Secondary analysis of 230 women and 158 men from the 1997/98 Ontario Food Survey. METHODS: Energy reporting quality was estimated by ratios of energy intake (EI) to both basal metabolic rate (BMR) and total energy expenditure (TEE). Multivariate regression analyses were conducted to examine energy reporting quality between two dietary recalls and in relation to body mass index (BMI) with adjustment for potential confounders. Energy reporting quality was explored across categories of age, BMI, income, education, dieting status and food insecurity through analysis of variance (ANOVA). RESULTS: From the ANOVA, energy reporting quality was associated with BMI group, age category and weight loss for men and women, as well as with education among women (P 0.05). EI:BMR and EI:TEE on the first and second 24-hour recalls were positively related (P < 0.0001 for men and women). A higher proportion of variance in energy reporting quality was explained for women than for men (R2 = 0.19 and 0.14, respectively). CONCLUSIONS: Studies of diet and adiposity are probably hindered to some extent by BMI-related variation in energy reporting quality. Methods to address this issue are urgently needed if population surveys will continue to serve as the primary source of dietary intake data.     

Two cases of atypical mycobacteriosis caused by Mycobacterium szulgai associated with mortality in captive African elephants (Loxodonta africana).

Mycobacterium szulgai was associated with mortality in two captive African elephants (Loxodonta africana) housed at Lincoln Park Zoo. The first elephant presented with severe, acute lameness of the left rear limb. Despite extensive treatments, the animal collapsed and died 13 mo after initial presentation. Necropsy revealed osteomyelitis with loss of the femoral head and acetabulum and pulmonary granulomas with intralesional M. szulgai. The second elephant collapsed during transport to another institution with no premonitory clinical signs. This animal was euthanized because of prolonged recumbency. Granulomatous pneumonia with intralesional M. szulgai was found at necropsy. Two novel immunoassays performed on banked serum samples detected antibody responses to mycobacterial antigens in both infected elephants. It was not possible to determine when the infection was established or how the elephants were infected. When reviewing the epidemiology of this organism in humans, however, transmission between elephants seemed unlikely because human-to-human transmission of this organism has never been reported and a third elephant in the herd was not affected. In addition to Mycobacterium bovis and Mycobacterium tuberculosis, atypical mycobacterial organisms need to be considered potentially pathogenic in elephants.     

Effects of low and high levels of maternal nutrition consumed for the entirety of gestation on the development of muscle,adipose tissue,bone, and the organs of Wagyu cattle fetuses

This study aimed to investigate the effects of high and low levels of energy intake during the entire gestation period on the skeletal muscle development, organ development, and adipose tissue accumulation in fetuses of Wagyu (Japanese Black) cows, a breed with highly marbled beef. Cows were allocated to a high-nutrition (n = 6) group (fed 120% of the nutritional requirement) or low-nutrition (n = 6) group (fed 60% of the nutritional requirement). The cows were artificially inseminated with semen from the same sire, and the fetuses were removed by cesarean section at 260 ± 8.3 days of fetal age and slaughtered. The whole-body, total muscle, adipose, and bone masses of the fetal half-carcasses were significantly higher in the high-nutrition group than the low-nutrition group (p = 0.0018, 0.009, 0.0004, and 0.0362, respectively). Fifteen of 20 individual muscles, five of six fat depots, nine of 17 organs, and seven of 12 bones that were investigated had significantly higher masses in the high-nutrition group than the low-nutrition group. The crude components and amino acid composition of the longissimus muscle significantly differed between the low- and high-nutrition groups. These data indicate that maternal nutrition during gestation has a marked effect on the muscle, bone, and adipose tissue development of Wagyu cattle fetuses.