Dataset Information

CRISPR-Cas9 generated SARM1 knockout and epitope tagged mice reveal no role in transcription, despite confirmation of protein expression in macrophages

ABSTRACT: The aim of this study was initially to determine the mechanism by which SARM1 regulates Ccl5 expression in murine macrophages. RNA sequencing revealed that the commonly used Sarm1tm1Aidi mouse, generated by targeted gene disruption, harbours passenger genes on chromosome 11 which confound interpretation of differential gene expression. Next-generation SARM1-deficient and epitope-tagged mice generated by CRISPR/Cas9 reveal no broad role for SARM1 in transcription in macrophages or brainstem, despite SARM1 protein expression there.

ORGANISM(S): Mus musculus

PROVIDER: GSE182091 | GEO | 2021/08/14

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Intracellular signaling regulators can be concentrated into membrane-free, higher-ordered protein assemblies to initiate protective responses during stress — a process known as phase transition. Here, we show that a phase transition of the Caenorhabditis elegans Toll/interleukin-1 receptor domain protein (TIR-1), an NAD+ glycohydrolase homologous to mammalian sterile alpha and TIR motif-containing 1 (SARM1), underlies p38 PMK-1 immune pathway activation in C. elegans intestinal epithelial cells. Through visualization of fluorescently labeled TIR-1/SARM1 protein, we demonstrate for the first time that physiologic stresses, both pathogen and non-pathogen, induce multimerization of TIR-1/SARM1 into visible puncta within intestinal epithelial cells. In vitro enzyme kinetic analyses revealed that, like mammalian SARM1, the NAD+ glycohydrolase activity of C. elegans TIR-1 is dramatically potentiated by protein oligomerization and a phase transition. Accordingly, C. elegans with genetic mutations that specifically block either multimerization or the NAD+ glycohydrolase activity of TIR-1/SARM1 fail to induce p38 PMK phosphorylation, are unable to increase immune effector expression, and are dramatically susceptible to bacterial infection. Finally, we demonstrate that low cholesterol stress causes TIR-1/SARM1 to oligomerize into puncta in intestinal epithelial cells and engages its NAD+ glycohydrolase activity, which increases p38 PMK-1 phosphorylation, and primes immune effector induction in a manner that leads to reduced pathogen accumulation in the intestine during a subsequent infection. These data reveal a new adaptive response that allows a metazoan host to anticipate pathogen threats during micronutrient deprivation, a time of relative susceptibility to infection. Thus, a phase transition of TIR-1/SARM1 as a prerequisite for its NAD+ glycohydrolase activity is strongly conserved across millions of years of evolution and is essential for diverse physiological processes in multiple cell types.

Dataset Information

CRISPR-Cas9 generated SARM1 knockout and epitope tagged mice reveal no role in transcription, despite confirmation of protein expression in macrophages

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure