The sirtuin SIRT6 regulates stress granule formation in C. elegans and mammals

SIRT6 is a NAD(+)-dependent deacetylase that modulates chromatin structure and safeguards genomic stability. Until now, SIRT6 has been assigned to the nucleus and only nuclear targets of SIRT6 are known. Here, we demonstrate that in response to stress, C. elegans SIR-2.4 and its mammalian orthologue SIRT6 localize to cytoplasmic stress granules, interact with various stress granule components and induce their assembly. Loss of SIRT6 or inhibition of its catalytic activity in mouse embryonic fibroblasts impairs stress granule formation and delays disassembly during recovery, whereas deficiency of SIR-2.4 diminishes maintenance of P granules and decreases survival of C. elegans under stress conditions. Our findings uncover a novel, evolutionary conserved function of SIRT6 in the maintenance of stress granules in response to stress.

MicroRNA regulation in experimental autoimmune encephalomyelitis in mice and marmosets resembles regulation in human multiple sclerosis lesions

Here we demonstrate that miRNA regulation in marmoset (Callithrix jacchus) and C57/BL6 mouse EAE lesions largely resembles miRNA regulation in active human MS lesions. Detailed quantitative PCR analyses of the most up- and downregulated miRNAs of active human MS lesions in dissected lesions from marmoset EAE brains and inflamed spinal cords of EAE mice revealed that the conserved and highly regulated miRNAs, miRNA-155, miRNA-142-3p, miRNA-146a, miRNA-146b and miRNA-21, turned out to be similarly upregulated in marmoset and mouse EAE lesions.