Project description:Brain-specific SIRT6-KO mice present increased DNA damage, learning impairments, and neurodegenerative phenotypes, placing SIRT6 as a key protein in preventing neurodegeneration. In the aging brain, SIRT6 levels/activity decline, which is accentuated in Alzheimer's patients. To understand SIRT6 roles in transcript pattern changes, we analyzed transcriptomes of young WT, old WT and young SIRT6-KO mice brains, and found changes in gene expression related to healthy and pathological aging. In addition, we traced these differences in human and mouse samples of Alzheimer's and Parkinson's diseases, healthy aging and calorie restriction (CR). Our results define four gene expression categories that change with age in a pathological or non-pathological manner, which are either reversed or not by CR. We found that each of these gene expression categories is associated with specific transcription factors, thus serving as potential candidates for their category-specific regulation. One of these candidates is YY1, which we found to act together with SIRT6 regulating specific processes. We thus argue that SIRT6 has a pivotal role in preventing age-related transcriptional changes in brains. Therefore, reduced SIRT6 activity may drive pathological age-related gene expression signatures in the brain.
Project description:Microarray analysis of liver tissue from WT SIRT6 and conditional knockout of SIRT6 using albumin-Cre (SIRT6Co/Co ;Alb-Cre) at 2 and 8 months of age RNA was extracted from mouse liver tissue at 2 and 8 months of age. RNA from three pairs of WT SIRT6 and SIRT6Co/Co ;Alb-Cre mice was combined and hybridized to Affymetrix mouse gene 1.0 ST arrays.
Project description:Brains are sexually dimorphic in adult zebrafish. We dissected brains from young and old, adult zebrafish, from both males and females. Brains are not pooled but analyzed as indivual samples.
Project description:Microarray analysis of liver tissue from WT SIRT6 and conditional knockout of SIRT6 using albumin-Cre (SIRT6Co/Co ;Alb-Cre) at 2 and 8 months of age
Project description:Brains are sexually dimorphic in adult zebrafish. We dissected brains from young and old, adult zebrafish, from both males and females. Brains are not pooled but analyzed as indivual samples. Four groups of wild-type zebrafish (AB strain) were used for this study: young (7.5-8.5 months old) male and female and old (31-36 months old) male and female. There were three animals per group for a total of 12 animals in the study.
Project description:The adaptor protein Lnk is an important negative regulator of HSC homeostasis and self-renewal. This study aims to investigate the role of Lnk in HSC aging. Here we performed expression profiling of bone marrow CD150+CD48-LSK LT-HSCs from young and old WT and Lnk-/- mice. Results identify select Lnk-mediated pathways with potential involvement in HSC self-renewal and aging.
Project description:The adaptor protein Lnk is an important negative regulator of HSC homeostasis and self-renewal. This study aims to investigate the role of Lnk in HSC aging. Here we performed expression profiling of bone marrow CD150+CD48-LSK LT-HSCs from young and old WT and Lnk-/- mice. Results identify select Lnk-mediated pathways with potential involvement in HSC self-renewal and aging. CD150+CD48-LSK HSCs were double sorted from WT and Lnk-/- mice at both young and old ages (2 months and 20 months, respectively). RNA was isolated using miRNeasy kit from QIAGEN and processed using the NuGEN Pico kit. The microarray analysis was performed at the Penn Molecular Profiling/Genomics Facility using GeneChip Mouse Gene 1.0ST array (Affymetrix).
Project description:Microarray analysis on total retinal RNA from 15 day old Sirt6 wild-type (WT) and knock-out (KO) mice. The retina is one of the major energy consuming tissues within the body. In this context, synaptic transmission between light-excited rod photoreceptors and downstream ON-bipolar neurons is a highly demanding energy consuming process. Sirtuin 6 (SIRT6), a NAD-dependent deacylase, plays a key role in regulating glucose metabolism. In this study, we demonstrate that SIRT6 is highly expressed in the retina, controlling levels of histone H3K9 and H3K56 acetylation. Notably, despite apparent normal histology, SIRT6 deficiency caused major retinal transmission defects concomitant to changes in expression of glycolytic genes and glutamate receptors, as well as elevated levels of apoptosis in inner retina cells. Our results identify SIRT6 as a critical modulator of retinal function, likely through its effects on chromatin. Microarray analysis of total retinal RNA from 15 day old Sirt6 wild-type (WT) and knock-out (KO) mice with 3 replicates in each condition using the Affymetrix Mouse Gene 2.1 ST array (transcript (gene) version).