Unfolding the complexities of ER chaperones in health and disease: report on the 11th international calreticulin workshop

The 11th International Calreticulin workshop was held May 15–18, 2015 at New York University School of Medicine-Langone Medical Center, New York. The meeting highlighted many of the new discoveries in the past 2 years involving the important role of molecular chaperones in physiological and pathological processes. Crucial to the understanding of these disease processes was the role of chaperones in maintaining quality control of protein processing in the endoplasmic reticulum, the importance of Ca² regulation acting through its action in stress-related diseases, and the trafficking of glycoproteins to the cell surface. Central to maintaining healthy cell physiology is the correct ER-associated protein degradation of specific misfolded proteins. Information on different mechanisms involved in the degradation of misfolded proteins was revealed. This was a landmark meeting for the chaperone field in terms of new insights into their roles in physiology. These insights included the unfolded protein response, innate/adaptive immunity, tissue repair, the functions of calreticulin/chaperones from the cell surface, and extracellular environment. Diseases included neurodegenerative disorders, prion disease, autoimmunity, fibrosis-related disease, the host immune response to cancer, and hematologic diseases associated with calreticulin mutations. The 12th calreticulin workshop is planned for the spring of 2017 in Delphi, Greece.     

Fungal variegatic acid and extracellular polysaccharides promote the site-specific generation of reactive oxygen species

Journal of Industrial Microbiology & Biotechnology - This study aims to clarify the role of variegatic acid (VA) in fungal attack by Serpula lacrymans, and also the generation and scavenging of...     

Marine invasion processes: interactions between native and introduced marsh snails

We test two hypotheses to explain the success of a biological invader in marshes on the Pacific coast of North America. The first hypothesis focuses on the competitive superiority of an invading species over native species; the second hypothesis focuses on the absence of ecological equivalents in the aboriginal biota, such that no competitive interactions are necessary to facilitate successful invasion. As a model system we experimentally manipulated the introduced pulmonate snail Ovatella myosotis and the native prosobranch snails Assiminea californica and Littorina subrotundata. Manipulations included pair-wise enclosures to determine of Ovatella depressed the growth of the native;species; pair-wise associations to determine whether or not snails demonstrated negative or positive clustering; removal experiments to see if native snails invaded regions occupied by Ovatella, and reciprocal transplants on a vertical gradient to determine the physiological breath of the target species. In addition to monitoring population abundances of all three species seasonally, dietary overlap of these gastropods was also examined. No evidence of competitive superiority by Ovatella was found. Ovatella possesses the physiological capacities to exist in a semiterrestrial environment and is therefore able to take advantage of resources unavailable to native gastropods. We conclude that the successful establishment of this Atlantic snail in the Pacific Northwest did not arise at the expense of native species.     

Reduction of Endotoxin Levels in Influenza Virus Vaccines by Barium Sulfate Adsorption-Elution

The level of endotoxin in influenza virus vaccine lots was reduced 10- to 20-fold after barium sulfate adsorption-elution. The amount of viral antigen lost was negligible.     

Analysis of global DNA methylation changes in human keratinocytes immediately following exposure to a 900 MHz radiofrequency field

The increasing use of nonionizing radiofrequency electromagnetic fields (RF-EMFs) in a wide range of technologies necessitates studies to further understanding of biological effects from exposures to such forms of electromagnetic fields. While previous studies have described mechanisms for cellular changes occurring following exposure to low-intensity RF-EMFs, the role of molecular epigenetics has not been thoroughly investigated. Specifically unresolved is the effect of RF-EMFs on deoxyribonucleic acid (DNA) methylation, which is a powerful epigenetic process, used by cells to regulate gene expression. DNA methylation is dynamic and can be rapidly triggered in response to external stimuli such as exposure to RF-EMFs. In the present study, we performed a global analysis of DNA methylation patterns in human keratinocytes exposed to 900 MHz RF-EMFs for 1 h at a low dose rate (estimated mean specific absorption rate (SAR) < 10 mW/kg). We used a custom system to allow stable exposure of cell cultures to RF-EMFs under biologically relevant conditions (37 °C, 5% CO₂, 95% humidity). We performed whole genome bisulfite sequencing directly following RF-EMF exposure to examine the immediate changes in DNA methylation patterns and identify early differentially methylated genes in RF-EMF-exposed keratinocytes. By correlating global gene expression to whole genome bisulfite sequencing, we identified six common targets that were both differentially methylated and differentially expressed in response to RF-EMF exposure. The results highlight a potential epigenetic role in the cellular response to RF-EMFs. Particularly, the six identified targets may potentially be developed as epigenetic biomarkers for immediate responses to RF-EMF exposure. Bioelectromagnetics. 1–13, © 2023 Bioelectromagnetics Society. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.     

Is there a relationship between branched amino acid pool size and cell cycle inhibition in roots treated with imidazolinone herbicides?

Excised pea root tips were cultured in White's medium for 24 h and then treated for 12 h with one of the imidazolinone herbicides at 0.2, 2, 20, or 200 μM. Pursuit and Assert were almost ineffective in inhibiting the mitotic index (MI), except at the highest concentrations. Arsenal (ARS) and Scepter both showed good inhibition with 20 μM by 8 h. Adding all three branched amino acids (BAA) (VAL, ILE, and LEU) at 0.1 mM blocked herbicide action. Treatment with the BAAs singly had no protective effect. Experiments were performed to determine the BAA pool size and MI after an 8-h treatment with ARS at 2 and 200 μM and Chlorsulfuron (CS), a sulfonylurea herbicide, at 28 nM. Both CS and ARS at 200 μM inhibited the MI to almost 0 by 8 h. ARS at 2 μM inhibited the MI by about 40%. The BAA pool size in all three treatments was reduced by approximately 50%, whether the MI was totally blocked or not. The 1-mm root tips had a greater amount of VAL than did the mature portions of the roots, whereas ILE and LEU were slightly less in the root tip. Other soluble amino acids did not show consistent differences between herbicide-treated roots and controls. The implications of the pool size reduction, in instances where the MI was not totally inhibited, is discussed in light of new data from other laboratories on the mode of action of the imidazolinone herbicides.