What does SKN-1 do?
During postembryonic stages, SKN-1 regulates a key Phase II detoxification gene through constitutive and stress-inducible mechanisms in the ASI chemosensory neurons and intestine, respectively. SKN-1 is present in ASI nuclei under normal conditions, and accumulates in intestinal nuclei in response to oxidative stress.
What tissue is SKN 1B expressed?
ASI neurons
SKN-1B is expressed in the ASI neurons, and mediates lifespan extension in response to dietary restriction [17].
Does SKN 1B increase lifespan?
SKN-1 contributes to the increased stress tolerance and longevity resulting from reduced IIS, and delays aging when expressed transgenically. Furthermore, SKN-1 that is constitutively active increases lifespan independently of DAF-16.
What does SKN-1 do to C elegans?
In C. elegans, the skn-1 gene encodes a transcription factor that resembles mammalian Nrf2 and activates a detoxification response.
Where is SKN-1B found?
SKN-1A and SKN-1C are expressed in the intestine and regulated, similarly to the Nrfs, at the level of cellular localisation [10,11]. In contrast, SKN-1B is expressed in two chemosensory neurons, the ASIs, which are thought to act as the worm’s hypothalamus, and is constitutively nuclear [3,10,12].
What are ASI neurons?
ASI neurons are the sole source of DAF-7/TGF-β in C. elegans. – Function in locomotion: Suppress omega turns and reversals enhancing dispersal (Gray et al., 2005). After animals are removed from bacterial food, they initiate a local search behavior consisting of reversals and deep omega-shaped turns.
Why is Arabidopsis thaliana used as a model organism?
A. thaliana is easy to look after compared with animal model organisms. It grows quickly, produces many very small seeds, has a small genome ~114.5 Mb and is genetically well characterised due to the volume of work being focused on this plant.
What is oxidative stress in C elegans?
Oxidative stress plays a central role in many human diseases and in aging. In Caenorhabditis elegans the SKN-1 protein induces phase II detoxification gene transcription, a conserved oxidative stress response, and is required for oxidative stress resistance and longevity.
What is the function of skn-1?
The stress resistance function of SKN-1 is mediated by its expression in the intestine (digestive system) ( Bishop and Guarente, 2007 ), where SKN-1 accumulates in nuclei and activates phase 2 gene expression inducibly in response to stress ( An and Blackwell, 2003 ).
Are there new skn-1-up-regulated genes?
These SKN-1-up-regulated genes include many from the expected categories of canonical detoxification target genes, but also other genes that suggest intriguing “new” SKN-1 functions.
How are skn-1 and NRF/CNC related?
SKN-1 and Nrf/CNC proteins are most closely related within the DIDLID and DNA-binding regions [6,17]. SKN-1 interacts directly with specific DNA sequences through its BR, which is highly similar to that of Nrf/CNC proteins, and a short element that binds in the minor groove (light blue) [11]. The CNC domain stabilizes these interactions.
Is skn-1 directly regulated by Nrf2?
The presence of predicted SKN-1 binding sites, together with chromatin immunoprecipitation (ChIP) analyses, suggests that most of these detoxification genes are regulated directly by SKN-1 [24,29,30,41,43,44]. Thus, like Nrf2, SKN-1 controls many critical detoxification processes directly.