The RAR1 interactor SGT1, an essential component of R gene-triggered disease resistance

Plant disease resistance (R) genes trigger innate immune responses upon pathogen attack. RAR1 is an early convergence point in a signaling pathway engaged by multiple R genes. Here, we show that RAR1 interacts with plant orthologs of the yeast protein SGT1, an essential regulator in the cell cycle. Silencing the barley gene Sgt1 reveals its role in R gene-triggered, Rar1-dependent disease resistance. SGT1 associates with SKP1 and CUL1, subunits of the SCF (Skp1-Cullin-F-box) ubiquitin ligase complex. Furthermore, the RAR1-SGT1 complex also interacts with two COP9 signalosome components. The interactions among RAR1, SGT1, SCF, and signalosome subunits indicate a link between disease resistance and ubiquitination.     

Silicon device scaling to the sub-10-nm regime

In the next decade, advances in complementary metal-oxide semiconductor fabrication will lead to devices with gate lengths (the region in the device that switches the current flow on and off) below 10 nanometers (nm), as compared with current gate lengths in chips that are now about 50 nm. However, conventional scaling will no longer be sufficient to continue device performance by creating smaller transistors. Alternatives that are being pursued include new device geometries such as ultrathin channel structures to control capacitive losses and multiple gates to better control leakage pathways. Improvement in device speed by enhancing the mobility of charge carriers may be obtained with strain engineering and the use of different crystal orientations. Here, we discuss challenges and possible solutions for continued silicon device performance trends down to the sub-10-nm gate regimes.     

Marcy: A chipping variety with resistance to common scab and the golden nematode

‘Marcy’ is a white-skinned, white-fleshed potato cultivar notable for its high yield, good chip color, and resistance to common scab and race Ro1 of the golden cyst nematode. It was selected from a cross made at Cornell University in 1990 between ‘Atlantic’ and Q155-3. Full-season marketable yields of Marcy have averaged 15% to 20% greater than Atlantic in 83 trials across New York, Maine, and Pennsylvania. Specific gravity of Marcy has averaged 0.008 less than Atlantic. Chip color out of 7 C storage in New York has been similar to ‘Pike’, but not as light as ‘Snowden’. Marcy tubers have an attractive oval shape, shallow eyes, and highly textured skin. Marcy was jointly released by the New York and Pennsylvania Agricultural Experiment Stations in 2002.     

Viral-derived DNA invasion and individual variation in an Indonesian population of large flying fox Pteropus vampyrus

Here, we performed next-generation sequencing (NGS) on six large flying foxes (Pteropus vampyrus) collected in Indonesia. Seventy-five virus species in the liver tissue of each specimen were listed. Viral homologous sequences in the bat genome were identified from the listed viruses. This finding provides collateral evidence of viral endogenization into the host genome. We found that two of the six specimens bore partial sequences that were homologous to the plant pathogens Geminiviridae and Luteoviridae. These sequences were absent in the P. vampyrus chromosomal sequences. Hence, plant viral homologous sequences were localized to the hepatocytes as extrachromosomal DNA fragments. Therefore, this suggests that the bat is a potential carrier or vector of plant viruses. The present investigation on wild animals offered novel perspectives on viral invasion, variation, and host interaction.     

Assessment of bovine mammary chemokine gene expression in response to lipopolysaccharide, lipotechoic acid + peptidoglycan, and CpG oligodeoxynucleotide 2135

During intramammary infections pathogen associated molecular patterns (PAMPs) induce an inflammatory response, recognized clinically as mastitis. Recognition of PAMPs by mammary cells leads to the production of the pro-inflammatory cytokines, TNF-α and IL-1β. These cytokines augment the secretion of various chemokines that are responsible for directing the host cellular immune response, and consequently the outcome of infection. Previous research has shown that gram-negative and gram-positive bacteria elicit different types of innate immune responses. The purpose of this study, therefore, was to characterize the expression of various chemokine genes in bovine mammary gland explants in response to lipopolysaccharide (LPS), peptidoglycan (PTG) combined with lipotechoic acid (LTA), and CpG oligodeoxynucleotide (CpG-ODN) 2135 representing gram-negative bacteria, gram-positive bacteria, and bacterial DNA, respectively, to determine if these PAMPs induce different chemokine gene expression patterns. Explants from 3 Holstein cows were cultured with 10 μg/mL of LPS, LTA + PTG, or CpG-ODN 2135 for 6 and 24 h. Total RNA was extracted and the expression of CXCL8, MCP-1, MCP-2, MCP-3, MIP1-α, and RANTES genes was measured by real-time polymerase chain reaction (RT-PCR). Lipopolysaccharide significantly induced MCP-1, MCP-2, and MCP-3 expression, and slightly increased CXCL8 gene expression. The combined PAMPs, LTA + PTG, on the other hand, significantly induced MCP-1 gene expression, and slightly increased MCP-3 expression. No significant expression differences for any of the chemokine genes were observed in explants stimulated with CpG-ODN 2135. These results demonstrate that PAMPs associated with different mastitis-causing pathogens induce chemokine-specific gene expression patterns that may contribute to different innate immune responses to bacteria.     

Evaluation of the California mastitis test to detect an intramammary infection with a major pathogen in early lactation dairy cows

The purpose of this study was to evaluate the usefulness of the California mastitis test (CMT) to detect an intramammary infection caused by a major mastitis pathogen in early lactation cows. The gold standard used for comparison was bacteriological culture of single milk samples. The sensitivity (82.4%) and specificity (80.6%) of a positive CMT were highest on the 4th day of lactation.