Background: Molecular chaperones assist proteins to gain their three-dimensional conformation or triage damaged proteins for degradation. Results: The chaperone Aha1 prevents aggregation of stressed denatured proteins and favors their ubiquitination. Conclusion: Aha1 may save the protein folding machinery from overload by misfolded proteins. Significance: This new function of Aha1 may be crucial to avoid harm to the cell.

Hsp90 (heat shock protein 90) is an essential molecular chaperone that mediates folding and quality control of client proteins. Many of them such as protein kinases, steroid receptors and transcription factors are involved in cellular signaling processes. Hsp90 undergoes an ATP hydrolysis dependent conformational cycle to assist folding of the client protein. The canonical Hsp90 shows a typical composition of three distinct domains and interacts with individual cochaperone partners such as Hop, Cdc37 and Aha1 (activator of Hsp90 ATPase) that regulate the reaction cycle of the molecular chaperone. A bioinformatic survey identified an additional domain of 122 amino acids in front of the canonical Hsp90 sequence. This extra domain (E domain) is specific to the Catarrhini or drooping nose monkeys, a subdivision of the higher primates that includes man, the great apes and the old world monkeys but is absent from all other species. Our biochemical analysis reveals that Hsp103 associates with cochaperone proteins such as Hop, Cdc37 and Aha1 similar to Hsp90. However, the extra domain reduces the ATP hydrolysis rate to about half when compared to Hsp90 thereby acting as a negative regulator of the molecular chaperonés intrinsic ATPase activity.

Background: Erectile dysfunction (ED) is a common medical condition that affects approximately 100 million men worldwide and is currently recognized as a major public health problem. Metabolic syndrome (Met S) is a complex entity consisting of multiple interrelated factors including insulin resistance, central adiposity, dyslipidaemia, endothelial dysfunction and atherosclerotic disease, low-grade inflammation, and in males, low testosterone levels. we aimed to investigate the relationship between metabolic syndrome and ED presence and severity.Methods: Patient who came to urology OPD with c/o of ED and were evaluated for it with physical examination, questionnaire, investigations>after confirmation of ED were evaluated for presence of metabolic syndrome and its individual componentsResults: Out of these 202 patients, 98 patients were found to have metabolic syndrome. The mean age of participating patients in this study was 47.2±5.6 years. Metabolic syndrome was diagnosed in 98 (34.78%) of 202 patients. Statistically significant association was found between ED and metabolic syndrome, waist circumference and fasting blood glucose (p<0.001 with each parameter). We also found a significant correlation between hypertension and ED but no significant correlation with triglyceride levels or HDL levels.Conclusions: ED is strongly associated with metabolic syndrome and the efforts for treatment of erectile dysfunction must be made in the context of metabolic syndrome and its constituents with a low threshold to diagnose the cardiovascular disease.