Proteasome Nuclear Import Mediated by Arc3 Can Influence Efficient DNA Damage Repair and Mitosis in Schizosaccharomyces Pombe

Proteasomes must efficiently remove their substrates throughout the cells in a timely manner as many of these proteins can be toxic. This study shows that proteasomes can do so efficiently because they are highly mobile. Furthermore this study uncovers that proteasome mobility requires functional Arc3, a subunit of the Arp2/3 complex

The Impact of Local Genome Sequence on Defining Heterochromatin Domains

Characterizing how genomic sequence interacts with trans-acting regulatory factors to implement a program of gene expression in eukaryotic organisms is critical to understanding genome function. One means by which patterns of gene expression are achieved is through the differential packaging of DNA into distinct types of chromatin. While chromatin state exerts a major influence on gene expression, the extent to which cis-acting DNA sequences contribute to the specification of chromatin state remains incompletely understood. To address this, we have used a fission yeast sequence element (L5), known to be sufficient to nucleate heterochromatin, to establish de novo heterochromatin domains in the Schizosaccharomyces pombe genome. The resulting heterochromatin domains were queried for the presence of H3K9 di-methylation and Swi6p, both hallmarks of heterochromatin, and for levels of gene expression. We describe a major effect of genomic sequences in determining the size and extent of such de novo heterochromatin domains. Heterochromatin spreading is antagonized by the presence of genes, in a manner that can occur independent of strength of transcription. Increasing the dosage of Swi6p results in increased heterochromatin proximal to the L5 element, but does not result in an expansion of the heterochromatin domain, suggesting that in this context genomic effects are dominant over trans effects. Finally, we show that the ratio of Swi6p to H3K9 di-methylation is sequence-dependent and correlates with the extent of gene repression. Taken together, these data demonstrate that the sequence content of a genomic region plays a significant role in shaping its response to encroaching heterochromatin and suggest a role of DNA sequence in specifying chromatin state

Survival rate of patients with esophageal squamous cell carcinoma

Background and Objective: Squamous carcinoma accounts for the majority of esophageal carcinoma worldwide. This study was done to evaluate the survival rate of patients with esophageal cancer in Iran. Methods: This historical cohort study was carried outon 105 patients with esophageal squamous cell carcinoma whom admitted to Firoozgar hospital in Tehran, Iran during 2009-14. Patients with esophageal squamous cell carcinoma were treated with chemoradiation either with or without surgery. Results: The mean age of patients was 63 years. Frequency of esophageal cancer in both sexes in the age group 51-60 years was higher than other groups. 5-year survival in patients with esophageal cancer treated with chemoradiation without surgery was 9.5% and in patients treated with chemoradiation with surgery was 31.7 % (P<0.05). One-year, three-year and five-year survival rate in patients were treated with chemoradiation with or without surgery was 68.5%, 38% and 22.8%, respectively. Conclusion: The survival rate of patients with esophageal cancer is very low, but the treatment with chemoradiation with surgery can increase life expectancy of patients