Evaluation of PRNP Expression Based on Genotypes and Alleles of Two Indel Loci in the Medulla Oblongata of Japanese Black and Japanese Brown Cattle

BACKGROUND: Prion protein (PrP) level plays the central role in bovine spongiform encephalopathy (BSE) susceptibility. Increasing the level of PrP decreases incubation period for this disease. Therefore, studying the expression of the cellular PrP or at least the messenger RNA might be used in selection for preventing the propagation of BSE and other prion diseases. Two insertion/deletion (indel) variations have been tentatively associated with susceptibility/resistance of cattle to classical BSE. METHODOLOGY/PRINCIPAL FINDINGS: We studied the expression of each genotype at the two indel sites in Japanese Black (JB) and Japanese Brown (JBr) cattle breeds by a standard curve method of real-time PCR. Five diplotypes subdivided into two categories were selected from each breed. The two cattle breeds were considered differently. Expression of PRNP was significantly (p<0.0001) greater in the homozygous deletion genotype at the 23-bp locus in JB breed. Compared to the homozygous genotypes, the expression of PRNP was significantly greater in the heterozygous genotype at the 12-bp locus in JB (p<0.0001) and in JBr (p = 0.0394) breeds. In addition, there was a statistical significance in the PRNP levels between the insertion and the deletion alleles of the 23-bp locus in JB (p = 0.0003) as well as in JBr (p = 0.0032). There was no significance in relation to sex, age, geographical location or due to their interactions (p>0.05). CONCLUSION: Our results suggest that the del/del genotype or at least its del allele may modulate the expression of PRNP at the 23-bp locus in the medulla oblongata of these cattle breeds

Measurement of the diffractive structure function in deep inelastic scattering at HERA

This paper presents an analysis of the inclusive properties of diffractive deep inelastic scattering events produced in $ep$ interactions at HERA. The events are characterised by a rapidity gap between the outgoing proton system and the remaining hadronic system. Inclusive distributions are presented and compared with Monte Carlo models for diffractive processes. The data are consistent with models where the pomeron structure function has a hard and a soft contribution. The diffractive structure function is measured as a function of \xpom, the momentum fraction lost by the proton, of $\beta$, the momentum fraction of the struck quark with respect to \xpom, and of $Q^2$. The \xpom dependence is consistent with the form \xpoma where $a~=~1.30~\pm~0.08~(stat)~^{+~0.08}_{-~0.14}~(sys)$ in all bins of $\beta$ and $Q^2$. In the measured $Q^2$ range, the diffractive structure function approximately scales with $Q^2$ at fixed $\beta$. In an Ingelman-Schlein type model, where commonly used pomeron flux factor normalisations are assumed, it is found that the quarks within the pomeron do not saturate the momentum sum rule.Comment: 36 pages, latex, 11 figures appended as uuencoded fil

Observation of hard scattering in photoproduction events with a large rapidity gap at HERA

Events with a large rapidity gap and total transverse energy greater than 5 GeV have been observed in quasi-real photoproduction at HERA with the ZEUS detector. The distribution of these events as a function of the $\gamma p$ centre of mass energy is consistent with diffractive scattering. For total transverse energies above 12 GeV, the hadronic final states show predominantly a two-jet structure with each jet having a transverse energy greater than 4 GeV. For the two-jet events, little energy flow is found outside the jets. This observation is consistent with the hard scattering of a quasi-real photon with a colourless object in the proton.Comment: 19 pages, latex, 4 figures appended as uuencoded fil

Frequencies of polymorphisms associated with BSE resistance differ significantly between Bos taurus, Bos indicus, and composite cattle

<p>Abstract</p> <p>Background</p> <p>Transmissible spongiform encephalopathies (TSEs) are neurodegenerative diseases that affect several mammalian species. At least three factors related to the host prion protein are known to modulate susceptibility or resistance to a TSE: amino acid sequence, atypical number of octapeptide repeats, and expression level. These factors have been extensively studied in breeds of <it>Bos taurus </it>cattle in relation to classical bovine spongiform encephalopathy (BSE). However, little is currently known about these factors in <it>Bos indicus </it>purebred or <it>B. indicus </it>× <it>B. taurus </it>composite cattle. The goal of our study was to establish the frequency of markers associated with enhanced susceptibility or resistance to classical BSE in <it>B. indicus </it>purebred and composite cattle.</p> <p>Results</p> <p>No novel or TSE-associated <it>PRNP</it>-encoded amino acid polymorphisms were observed for <it>B. indicus </it>purebred and composite cattle, and all had the typical number of octapeptide repeats. However, differences were observed in the frequencies of the 23-bp and 12-bp insertion/deletion (indel) polymorphisms associated with two bovine <it>PRNP </it>transcription regulatory sites. Compared to <it>B. taurus</it>, <it>B. indicus </it>purebred and composite cattle had a significantly lower frequency of 23-bp insertion alleles and homozygous genotypes. Conversely, <it>B. indicus </it>purebred cattle had a significantly higher frequency of 12-bp insertion alleles and homozygous genotypes in relation to both <it>B. taurus </it>and composite cattle. The origin of these disparities can be attributed to a significantly different haplotype structure within each species.</p> <p>Conclusion</p> <p>The frequencies of the 23-bp and 12-bp indels were significantly different between <it>B. indicus </it>and <it>B. taurus </it>cattle. No other known or potential risk factors were detected for the <it>B. indicus </it>purebred and composite cattle. To date, no consensus exists regarding which bovine <it>PRNP </it>indel region is more influential with respect to classical BSE. Should one particular indel region and associated genotypes prove more influential with respect to the incidence of classical BSE, differences regarding overall susceptibility and resistance for <it>B. indicus </it>and <it>B. taurus </it>cattle may be elucidated.</p

Measurement of Charged and Neutral Current e-p Deep Inelastic Scattering Cross Sections at High Q2

Deep inelastic e-p scattering has been studied in both the charged current (CC) and neutral current (NC) reactions at momentum transfers squared Q(2) above 400 GeV2 using the ZEUS detector at the HERA ep collider. The CC and NC total cross sections, the NC to CC cross section ratio, and the differential cross sections d sigma/dQ(2) are presented. From the Q(2) dependence of the CC cross section, the mass term in the CC propagator is determined to be M(W) = 76 +/- 16 +/- 13 GeV