Dataset Information

Akt1 Controls the Timing and Amplitude of Vascular Circadian Gene Expression.

ABSTRACT: The AKT signaling pathway is important for circadian rhythms in mammals and flies ( Drosophila). However, AKT signaling in mammals is more complicated since there are 3 isoforms of AKT, each performing slightly different functions. Here we study the most ubiquitous AKT isoform, Akt1, and its role at the organismal level in the central and vascular peripheral clocks. Akt1-/- mice exhibit relatively normal behavioral rhythms with only minor differences in circadian gene expression in the liver and heart. However, circadian gene expression in the Akt1-/- aorta, compared with control aorta, follows a distinct pattern. In the Akt1-/- aorta, positive regulators of circadian transcription have lower amplitude rhythms and peak earlier in the day, and negative circadian regulators are expressed at higher amplitudes and peak later in the day. In endothelial cells, negative circadian regulators exhibit an increased amplitude of expression, while the positive circadian regulators are arrhythmic with a decreased amplitude of expression. This indicates that Akt1 conditions the normal circadian rhythm in the vasculature more so than in other peripheral tissues where other AKT isoforms or kinases might be important for daily rhythms.

SUBMITTER: Luciano AK

PROVIDER: S-EPMC5703205 | biostudies-other | 2017 Jun

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Akt1 Controls the Timing and Amplitude of Vascular Circadian Gene Expression.

Luciano Amelia K AK Santana Jeans M JM Velazquez Heino H Sessa William C WC

Journal of biological rhythms 20170428 3

The AKT signaling pathway is important for circadian rhythms in mammals and flies ( Drosophila). However, AKT signaling in mammals is more complicated since there are 3 isoforms of AKT, each performing slightly different functions. Here we study the most ubiquitous AKT isoform, Akt1, and its role at the organismal level in the central and vascular peripheral clocks. Akt1<sup>-/-</sup> mice exhibit relatively normal behavioral rhythms with only minor differences in circadian gene expression in th ...[more]

PMID: 28452287

Similar Datasets

Project description:Bioluminescence rhythms from cellular reporters have become the most common method used to quantify oscillations in circadian gene expression. These experimental systems can reveal phase and amplitude change resulting from circadian disturbances, and can be used in conjunction with mathematical models to lend further insight into the mechanistic basis of clock amplitude regulation. However, bioluminescence experiments track the mean output from thousands of noisy, uncoupled oscillators, obscuring the direct effect of a given stimulus on the genetic regulatory network. In many cases, it is unclear whether changes in amplitude are due to individual changes in gene expression level or to a change in coherence of the population. Although such systems can be modeled using explicit stochastic simulations, these models are computationally cumbersome and limit analytical insight into the mechanisms of amplitude change. We therefore develop theoretical and computational tools to approximate the mean expression level in large populations of noninteracting oscillators, and further define computationally efficient amplitude response calculations to describe phase-dependent amplitude change. At the single-cell level, a mechanistic nonlinear ordinary differential equation model is used to calculate the transient response of each cell to a perturbation, whereas population-level dynamics are captured by coupling this detailed model to a phase density function. Our analysis reveals that amplitude changes mediated at either the individual-cell or the population level can be distinguished in tissue-level bioluminescence data without the need for single-cell measurements. We demonstrate the effectiveness of the method by modeling experimental bioluminescence profiles of light-sensitive fibroblasts, reconciling the conclusions of two seemingly contradictory studies. This modeling framework allows a direct comparison between in vitro bioluminescence experiments and in silico ordinary differential equation models, and will lead to a better quantitative understanding of the factors that affect clock amplitude.

Dataset Information

Akt1 Controls the Timing and Amplitude of Vascular Circadian Gene Expression.

Publications

Akt1 Controls the Timing and Amplitude of Vascular Circadian Gene Expression.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets