Phosphorylation-Driven Epichaperome Assembly: A Critical Regulator of Cellular Adaptability and Proliferation

The intricate protein-chaperone network is vital for cellular function. Recent discoveries have unveiled the existence of specialized chaperone complexes called epichaperomes, protein assemblies orchestrating the reconfiguration of protein-protein interaction networks, enhancing cellular adaptability and proliferation. This study delves into the structural and regulatory aspects of epichaperomes, with a particular emphasis on the significance of post-translational modifications in shaping their formation and function. A central finding of this investigation is the identification of specific PTMs on HSP90, particularly at residues Ser226 and Ser255 situated within an intrinsically disordered region, as critical determinants in epichaperome assembly. Our data demonstrate that the phosphorylation of these serine residues enhances HSP90's interaction with other chaperones and co-chaperones, creating a microenvironment conducive to epichaperome formation. Furthermore, this study establishes a direct link between epichaperome function and cellular physiology, especially in contexts where robust proliferation and adaptive behavior are essential, such as cancer and stem cell maintenance. These findings not only provide mechanistic insights but also hold promise for the development of novel therapeutic strategies targeting chaperone complexes in diseases characterized by epichaperome dysregulation, bridging the gap between fundamental research and precision medicine.

Early Changes in Immune Cell Count, Metabolism, and Function Following Sleeve Gastrectomy: A Prospective Human Study

OBJECTIVE

To characterize longitudinal changes in blood biomarkers, leukocyte composition, and gene expression following laparoscopic sleeve gastrectomy (LSG).

BACKGROUND

LSG is an effective treatment for obesity, leading to sustainable weight loss and improvements in obesity-related comorbidities and inflammatory profiles. However, the effects of LSG on immune function and metabolism remain uncertain.

METHODS

Prospective data were collected from 23 enrolled human subjects from a single institution. Parameters of weight, comorbidities, and trends in blood biomarkers and leukocyte subsets were observed from preoperative baseline to 1 year postsurgery in 3-month follow-up intervals. RNA sequencing was performed on pairs of whole blood samples from the first 6 subjects of the study (baseline and 3 months postsurgery) to identify genome-wide gene expression changes associated with undergoing LSG.

RESULTS

LSG led to a significant decrease in mean total body weight loss (18.1%) at 3 months and among diabetic subjects a reduction in hemoglobin A1c. Improvements in clinical inflammatory and hormonal biomarkers were demonstrated as early as 3 months after LSG. A reduction in neutrophil-lymphocyte ratio was observed, driven by a reduction in absolute neutrophil counts. Gene set enrichment analyses of differential whole blood gene expression demonstrated that after 3 months LSG induced transcriptomic changes not only in inflammatory cytokine pathways but also in several key metabolic pathways related to energy metabolism.

CONCLUSIONS

LSG induces significant changes in the composition and metabolism of immune cells as early as 3 months postoperatively. Further evaluation is required of bariatric surgery's effects on immunometabolism and the consequences for host defense and metabolic disease.

Large-Scale Recombinant Production of the SARS-CoV-2 Proteome for High-Throughput and Structural Biology Applications

The highly infectious disease COVID-19 caused by the Betacoronavirus SARS-CoV-2 poses a severe threat to humanity and demands the redirection of scientific efforts and criteria to organized research projects. The international COVID19-NMR consortium seeks to provide such new approaches by gathering scientific expertise worldwide. In particular, making available viral proteins and RNAs will pave the way to understanding the SARS-CoV-2 molecular components in detail. The research in COVID19-NMR and the resources provided through the consortium are fully disclosed to accelerate access and exploitation. NMR investigations of the viral molecular components are designated to provide the essential basis for further work, including macromolecular interaction studies and high-throughput drug screening. Here, we present the extensive catalog of a holistic SARS-CoV-2 protein preparation approach based on the consortium's collective efforts. We provide protocols for the large-scale production of more than 80% of all SARS-CoV-2 proteins or essential parts of them. Several of the proteins were produced in more than one laboratory, demonstrating the high interoperability between NMR groups worldwide. For the majority of proteins, we can produce isotope-labeled samples of HSQC-grade. Together with several NMR chemical shift assignments made publicly available on covid19-nmr.com, we here provide highly valuable resources for the production of SARS-CoV-2 proteins in isotope-labeled form.

Early changes in immune cell metabolism and function are a hallmark of sleeve gastrectomy: a prospective human study

OBJECTIVE

To characterize longitudinal changes in blood biomarkers, leukocyte composition, and gene expression following laparoscopic sleeve gastrectomy (LSG).

BACKGROUND

LSG is an effective treatment for obesity, leading to sustainable weight loss and improvements in obesity-related co-morbidities and inflammatory profiles. However, the effects of LSG on immune function and metabolism remain uncertain.

METHODS

Prospective data was collected from 23 enrolled human subjects from a single institution. Parameters of weight, co-morbidities, and trends in blood biomarkers and leukocyte subsets were observed from pre-operative baseline to one year in three-month follow-up intervals. RNA-sequencing was performed on pairs of whole blood samples from the first six subjects of the study (baseline and three months post-surgery) to identify genome-wide gene expression changes associated with undergoing LSG.

RESULTS

LSG led to a significant decrease in mean total body weight loss (18.1%) at three months and among diabetic subjects a reduction in HbA1c. Improvements in clinical inflammatory and hormonal biomarkers were demonstrated as early as three months after LSG. A reduction in neutrophil-lymphocyte ratio was observed, driven by a reduction in absolute neutrophil counts. Gene set enrichment analyses of differential whole blood gene expression demonstrated that after three months, LSG induced transcriptomic changes not only in inflammatory cytokine pathways but also in several key metabolic pathways related to energy metabolism.

CONCLUSIONS

LSG induces significant changes in the composition and metabolism of immune cells as early as three months post-operatively. Further evaluation is required of bariatric surgery's effects on immunometabolism and consequences for host defense and metabolic disease.

A longitudinal study of the dietary practices of black and white girls 9 and 10 years old at enrollment: the NHLBI Growth and Health Study

PURPOSE

To determine whether there are racial differences in the frequency with which black and white girls engaged in eating practices commonly targeted for modification in weight reduction programs.

METHODS

This is part of the NHLBI Growth and Health Study, a longitudinal study of preadolescent girls designed to examine the factors associated with development of obesity, and its later effects on cardiovascular risk factors. Black and white girls ages 9-10 years at entry (n = 2,379) were recruited at three clinical sites. Racial differences were examined in 11 "weight-related" eating practices such as eating with TV, eating while doing homework, and skipping meals. Multiple logistic regression analyses were then conducted for each of the dependent variables.

RESULTS

Black girls were more than twice as likely as white girls to frequently engage in the targeted weight-related eating practices. The odds of a study girl frequently engaging in most of these eating practices decreased with an increase in parents' income and education level. However, even when controlling for socioeconomic and demographic effects, black girls remained more likely to engage in these eating practices than white girls. For most of the behaviors, girls who frequently practiced a behavior had higher energy intakes compared to those who practiced it infrequently.

CONCLUSIONS

The finding that black girls at an early age more frequently engage in eating practices associated with weight gain may have significant implications for obesity development. For both young black and white girls, early education efforts may be necessary in helping develop good eating habits. Since it appears that black girls have a higher risk of developing adverse weight-related eating practices, culturally appropriate education materials may be required.

Nutritional evaluation of soldiers subsisting on meal, ready-to-eat operational rations for an extended period: body measurements, hydration, and blood nutrients

To evaluate the nutritional value of a new military operational ration, meal, ready-to-eat (MRE), 27 soldiers were fed the ration as their only food during a 34-d field exercise at an elevation of 1800 m. Thirty soldiers given hot breakfasts and dinners and MREs for lunch served as control subjects. Measurements were made of body height, weight, skinfold thickness at four sites, urine volume and concentration, urinary zinc loss, hemoglobin, hematocrit, serum alkaline phosphatase activity, serum concentrations of albumin, total protein, ascorbic acid, folate, retinol, and Zn, and plasma pyridoxal phosphate concentration. The men fed only MREs experienced significant weight loss compared with those fed hot meals. Neither group appeared to be dehydrated. Hemoglobin and hematocrit values rose in response to increased elevation. Both groups of soldiers displayed normal values, indicative of acceptable nutritional status, of serum proteins, measured vitamins, and Zn.

Altered zinc status of soldiers under field conditions

Thirty men were studied during a 34-day intensive training exercise conducted by the U.S. Army. All soldiers were followed to determine the effect of such training, designed to simulate wartime operations, on selected zinc parameters. The soldiers consumed a nutritionally adequate diet made from fresh foods (A rations) prepared at the training site. Dietary intake, weight change, serum zinc, alkaline phosphatase activity, and urinary zinc excretion were measured. The 34-day intensive training exercise was associated with weight loss, depressed serum zinc levels, and elevated urinary zinc excretion. Alkaline phosphatase activity was not altered by the training exercise. The depressed serum zinc concentration could not be explained by the parameters measured. Weight loss was positively correlated with urinary zinc excretion. The functional significance of a depressed serum zinc concentration on performance deserves further study.