Hsp70 and Hsp40 inhibit an inter-domain interaction necessary for transcriptional activity in the androgen receptor.

Molecular chaperones such as Hsp40 and Hsp70 hold the androgen receptor (AR) in an inactive conformation. They are released in the presence of androgens, enabling transactivation and causing the receptor to become aggregation-prone. Here we show that these molecular chaperones recognize a region of the AR N-terminal domain (NTD), including a FQNLF motif, that interacts with the AR ligand-binding domain (LBD) upon activation. This suggests that competition between molecular chaperones and the LBD for the FQNLF motif regulates AR activation. We also show that, while the free NTD oligomerizes, binding to Hsp70 increases its solubility. Stabilizing the NTD-Hsp70 interaction with small molecules reduces AR aggregation and promotes its degradation in cellular and mouse models of the neuromuscular disorder spinal bulbar muscular atrophy. These results help resolve the mechanisms by which molecular chaperones regulate the balance between AR aggregation, activation and quality control

Isolation of acid soluble collagen from daggertooth pike conger (Muraenesox cinereus) and evaluation of its antimicrobial activity

The study was conducted to isolate acid soluble collagen (ASC) from daggertooth pike conger eel and to evaluate the antimicrobial activity of the isolated protein. Conger eels were collected from Kochi harbour. The proximate composition of eel skin consisted of 68.73 per cent of moisture on a wet basis with a crude protein, crude fat and total ash of 30.24 per cent, 12.17 per cent and 2.16 per cent respectively on a dry matter basis. Conger eel skin collagen was isolated by treating with 0.5 M acetic acid after pretreatment with 0.1 N NaOH and 10 per cent butanol. Salting out and precipitation of ASC was carried out by adding NaCl to a final concentration of 2.3 M. Precipitated ASC was then dialysed against 0.1 M acetic acid for 24h and then in distilled water until neutral pH was obtained. The yield of ASC was 12.78 per cent on a wet basis and 31.95 per cent on a dry basis. The antimicrobial activity of ASC was determined by the agar diffusion method. ASC showed antimicrobial activity against both E. coli and S. aureus

Author Correction: Hsp70 and Hsp40 inhibit an inter-domain interaction necessary for transcriptional activity in the androgen receptor.

An amendment to this paper has been published and can be accessed via a link at the top of the paper

Diaphragm Muscle Weakness in an Experimental Porcine Intensive Care Unit Model

In critically ill patients, mechanisms underlying diaphragm muscle remodeling and resultant dysfunction contributing to weaning failure remain unclear. Ventilator-induced modifications as well as sepsis and administration of pharmacological agents such as corticosteroids and neuromuscular blocking agents may be involved. Thus, the objective of the present study was to examine how sepsis, systemic corticosteroid treatment (CS) and neuromuscular blocking agent administration (NMBA) aggravate ventilator-related diaphragm cell and molecular dysfunction in the intensive care unit. Piglets were exposed to different combinations of mechanical ventilation and sedation, endotoxin-induced sepsis, CS and NMBA for five days and compared with sham-operated control animals. On day 5, diaphragm muscle fibre structure (myosin heavy chain isoform proportion, cross-sectional area and contractile protein content) did not differ from controls in any of the mechanically ventilated animals. However, a decrease in single fibre maximal force normalized to cross-sectional area (specific force) was observed in all experimental piglets. Therefore, exposure to mechanical ventilation and sedation for five days has a key negative impact on diaphragm contractile function despite a preservation of muscle structure. Post-translational modifications of contractile proteins are forwarded as one probable underlying mechanism. Unexpectedly, sepsis, CS or NMBA have no significant additive effects, suggesting that mechanical ventilation and sedation are the triggering factors leading to diaphragm weakness in the intensive care unit

Targeting resistance to radiation-immunotherapy in cold HNSCCs by modulating the Treg-dendritic cell axis.

BACKGROUND: Numerous trials combining radiation therapy (RT) and immunotherapy in head and neck squamous cell carcinoma (HNSCC) are failing. Using preclinical immune cold models of HNSCC resistant to RT-immune checkpoint inhibitors, we investigate therapeutic approaches of overcoming such resistance by examining the differential microenvironmental response to RT. METHODS: We subjected two HPV-negative orthotopic mouse models of HNSCC to combination RT, regulatory T cells (Treg) depletion, and/or CD137 agonism. Tumor growth was measured and intratumorous and lymph node immune populations were compared among treatment groups. Human gene sets, genetically engineered mouse models DEREG and BATF3-/-, flow and time-of-flight cytometry, RNA-Seq, Treg adoptive transfer studies, and in vitro experiments were used to further evaluate the role of dendritic cells (DCs) and Tregs in these treatments. RESULTS: In MOC2 orthotopic tumors, we find no therapeutic benefit to targeting classically defined immunosuppressive myeloids, which increase with RT. In these radioresistant tumors, supplementing combination RT and Treg depletion with anti-CD137 agonism stimulates CD103+ DC activation in tumor-draining lymph nodes as characterized by increases in CD80+ and CCR7+ DCs, resulting in a CD8 T cell-dependent response. Simultaneously, Tregs are reprogrammed to an effector phenotype demonstrated by increases in interferonγ+, tumor necrosis factorα+, PI3K+, pAKT+ and Eomes+ populations as well as decreases in CTLA4+ and NRP-1+ populations. Tumor eradication is observed when RT is increased to an 8 Gy x 5 hypofractionated regimen and combined with anti-CD25+ anti-CD137 treatment. In a human gene set from oral squamous cell carcinoma tumors, high Treg number is associated with earlier recurrence. CONCLUSIONS: Regulating Treg functionality and DC activation status within the lymph node is critical for generating a T cell effector response in these highly radioresistant tumors. These findings underscore the plasticity of Tregs and represent a new therapeutic opportunity for reprogramming the tumor microenvironment in HNSCCs resistant to conventional radioimmunotherapy approaches

Identification and sequence analysis of Tapasin gene in guinea fowl

Aim: An attempt has been made to identify and study the nucleotide sequence variability in exon 5 - exon 6 regions of guinea fowl Tapasin gene. Materials and Methods: Blood samples were collected from randomly selected birds (12 guinea fowl birds) and Tapasin gene amplified using chicken specific primers designed from GenBank submitted sequences. Polymerase chain reaction conditions were standardized so as get only single amplicons. Obtained products were then cloned and sequenced; sequences were then analyzed using suitable software. Results: Amplicon size of the Tapasin gene in guinea fowl was same as reported in chicken with areas of transitions and transversions. The sequence variations reported in these coding sequences might have influence in the protein structure, which may be correlated with the increased immune status of the bird when compared with chicken breeds. Conclusion: Since Tapasin gene is an immunologically important gene, which plays an important role in the immune status of the bird. Sequence variations in the gene can be correlated with the altered immune status of the bird