Identification of AMPK Phosphorylation Sites Reveals a Network of Proteins Involved in Cell Invasion and Facilitates Large-Scale Substrate Prediction

Schaffer, Bethany E.; Levin, Rebecca S.; Hertz, Nicholas T.; Maures, Travis J.; Schoof, Michael L.; Hollstein, Pablo E.; Benayoun, Bérénice A.; Banko, Max R.; Shaw, Reuben J.; Shokat, Kevan M.; Brunet, Anne

doi:10.1016/j.cmet.2015.09.009

Cited by 153 publications

(146 citation statements)

References 63 publications

(116 reference statements)

Supporting

Mentioning

135

Contrasting

Order By: Relevance

“…(Datasets S1-S4). Thus, although Western detection of thiophosphorylation is a useful tool, it is limited in comparison with MS results as observed in this study and others (20).…”

Section: Resultsmentioning

confidence: 84%

Innate immunity kinase TAK1 phosphorylates Rab1 on a hotspot for posttranslational modifications by host and pathogen

Levin

Hertz

Burlingame

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

TGF-β activated kinase 1 (TAK1) is a critical signaling hub responsible for translating antigen binding signals to immune receptors for the activation of the AP-1 and NF-κB master transcriptional programs. Despite its importance, known substrates of TAK1 are limited to kinases of the MAPK and IKK families and include no direct effectors of biochemical processes. Here, we identify over 200 substrates of TAK1 using a chemical genetic kinase strategy. We validate phosphorylation of the dynamic switch II region of GTPase Rab1, a mediator of endoplasmic reticulum to Golgi vesicular transport, at T75 to be regulated by TAK1 in vivo. TAK1 preferentially phosphorylates the inactive (GDP-bound) state of Rab1. Phosphorylation of Rab1 disrupts interaction with GDP dissociation inhibitor 1 (GDI1), but not guanine exchange factor (GEF) or GTPaseactivating protein (GAP) enzymes, and is exclusive to membranelocalized Rab1, suggesting phosphorylation may stimulate Rab1 membrane association. Furthermore, we found phosphorylation of Rab1 at T75 to be essential for Rab1 function. Previous studies established that the pathogen Legionella pneumophila is capable of hijacking Rab1 function through posttranslational modifications of the switch II region. Here, we present evidence that Rab1 is regulated by the host in a similar fashion, and that the innate immunity kinase TAK1 and Legionella effectors compete to regulate Rab1 by switch II modifications during infection.

show abstract

“…(Datasets S1-S4). Thus, although Western detection of thiophosphorylation is a useful tool, it is limited in comparison with MS results as observed in this study and others (20).…”

Section: Resultsmentioning

confidence: 84%

Innate immunity kinase TAK1 phosphorylates Rab1 on a hotspot for posttranslational modifications by host and pathogen

Levin

Hertz

Burlingame

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…We found evidence that metformin enhanced AUF1 binding to HSP70 and increased HSP70 localization in the nucleus. Interestingly, a ~70 kDa band that was serine–threonine‐phosphorylated in AUF1 immunoprecipitates might represent HSP70, recently identified as a substrate of AMPK (Schaffer et al ., 2015). It has been observed that phosphorylation of AUF1 has been reported to regulate AUF1 protein stability and binding to target mRNAs (Wilson et al ., 2003; Li et al ., 2013).…”

Section: Discussionmentioning

confidence: 99%

Metformin‐mediated increase in DICER1 regulates microRNA expression and cellular senescence

et al. 2016

View full text Add to dashboard Cite

SummaryMetformin, an oral hypoglycemic agent, has been used for decades to treat type 2 diabetes mellitus. Recent studies indicate that mice treated with metformin live longer and have fewer manifestations of age‐related chronic disease. However, the molecular mechanisms underlying this phenotype are unknown. Here, we show that metformin treatment increases the levels of the microRNA‐processing protein DICER1 in mice and in humans with diabetes mellitus. Our results indicate that metformin upregulates DICER1 through a post‐transcriptional mechanism involving the RNA‐binding protein AUF1. Treatment with metformin altered the subcellular localization of AUF1, disrupting its interaction with DICER1 mRNA and rendering DICER1 mRNA stable, allowing DICER1 to accumulate. Consistent with the role of DICER1 in the biogenesis of microRNAs, we found differential patterns of microRNA expression in mice treated with metformin or caloric restriction, two proven life‐extending interventions. Interestingly, several microRNAs previously associated with senescence and aging, including miR‐20a, miR‐34a, miR‐130a, miR‐106b, miR‐125, and let‐7c, were found elevated. In agreement with these findings, treatment with metformin decreased cellular senescence in several senescence models in a DICER1‐dependent manner. Metformin lowered p16 and p21 protein levels and the abundance of inflammatory cytokines and oncogenes that are hallmarks of the senescence‐associated secretory phenotype (SASP). These data lead us to hypothesize that changes in DICER1 levels may be important for organismal aging and to propose that interventions that upregulate DICER1 expression (e.g., metformin) may offer new pharmacotherapeutic approaches for age‐related disease.

show abstract

“…In addition to a pivotal regulatory function in metabolism, AMPK has been recently shown to modulate cell invasion [49]. Cell invasion is an energy consuming process, thus FA oxidation should play an important role in the regulation of trophoblast invasion due to its high efficiency in ATP production.…”

Section: Discussionmentioning

confidence: 99%

AMPK Hyper-Activation Alters Fatty Acids Metabolism and Impairs Invasiveness of Trophoblasts in Preeclampsia

Yang

Zhang

et al. 2018

Cell Physiol Biochem

View full text Add to dashboard Cite

Background/Aims: Preeclampsia (PE) has long been assumed to be an ischemic disease of the placenta, although there is limited evidence as to how the ischemia impacts on the placenta. AMP-activated protein kinase (AMPK) is a key regulator of cellular energy metabolism and plays an important role in a variety of ischemic diseases by enhancing energy production. The present study investigated placental metabolism in PE, and the role of AMPK in regulating trophoblast function. Methods: placentas from normal and PE complicated pregnancies were subjected to GC-MS to identify fatty acids (FA) metabolic fingerprints, and total FA oxidation was assessed by malondialdehyde (MDA) measurement. The AMPK-ACC signaling pathway was assessed by q-PCR and Western Blotting. HTR8/SVneo trophoblast cultures were exposed to different oxygenation conditions to establish an in vitro PE cell model; further analysis by GC-MS for metabolite profiling was then undertaken. Trophoblasts invasion was assessed by a matrigel transwell assay in the presence/absence of AMPK expression and after manipulations of AMPK activity, and then further validated by human villi outgrowth experiments. Results: AMPK phosphorylation and MDA production were significantly elevated in placentas from pregnancies complicated by PE. Metabolism of cis double bond FA was inhibited while trans double bond FA metabolism was promoted in PE placentas. HTR8/SVneo cell culture conditions of persistent low oxygenation mimicked the hyper-activation of AMPK and enhanced the FA oxidation that was observed in PE. AMPK activation impaired trophoblast invasion, while AMPK inhibition promoted trophoblast invasion. Conclusion: PE complicated placentas are associated with AMPK hyper-activation and consequent alterations in FA oxidation, which inhibit trophoblast invasion.

show abstract

Identification of AMPK Phosphorylation Sites Reveals a Network of Proteins Involved in Cell Invasion and Facilitates Large-Scale Substrate Prediction

Cited by 153 publications

References 63 publications

Innate immunity kinase TAK1 phosphorylates Rab1 on a hotspot for posttranslational modifications by host and pathogen

Innate immunity kinase TAK1 phosphorylates Rab1 on a hotspot for posttranslational modifications by host and pathogen

Metformin‐mediated increase in DICER1 regulates microRNA expression and cellular senescence

AMPK Hyper-Activation Alters Fatty Acids Metabolism and Impairs Invasiveness of Trophoblasts in Preeclampsia

Contact Info

Product

Resources

About