Interactome Mapping of the Phosphatidylinositol 3-Kinase-Mammalian Target of Rapamycin Pathway Identifies Deformed Epidermal Autoregulatory Factor-1 as a New Glycogen Synthase Kinase-3 Interactor

Abstract

The phosphatidylinositol 3-kinase-mammalian target of rapamycin (PI3K-mTOR) pathway plays pivotal roles in cell survival, growth, and proliferation downstream of growth factors. Its perturbations are associated with cancer progression, type 2 diabetes, and neurological disorders. To better understand the mechanisms of action and regulation of this pathway, we initiated a large scale yeast two-hybrid screen for 33 components of the PI3K-mTOR pathway. Identification of 67 new interactions was followed by validation by co-affinity purification and exhaustive literature curation of existing information. We provide a nearly complete, functionally annotated interactome of 802 interactions for the PI3K-mTOR pathway. Our screen revealed a predominant place for glycogen synthase kinase-3 (GSK3) A and B and the AMP-activated protein kinase. In particular, we identified the deformed epidermal autoregulatory factor-1 (DEAF1) transcription factor as an interactor and in vitro substrate of GSK3A and GSK3B. Moreover, GSK3 inhibitors increased DEAF1 transcriptional activity on the 5-HT1A serotonin receptor promoter. We propose that DEAF1 may represent a therapeutic target of lithium and other GSK3 inhibitors used in bipolar disease and depression. Molecular & Cellular Proteomics 9:1578 -1593, 2010.The phosphatidylinositol 3-kinases (PI3Ks) 1 are a conserved family of lipid kinases that phosphorylate phosphatidylinositol on phosphoinositide 3Ј-hydroxyl group, forming second messengers. Class IA PI3K (hereafter "PI3K") is activated by growth factor receptor tyrosine kinases, and upon stimulation by insulin or IGF1, PI3K triggers the formation of phosphatidylinositol 3,4,5-trisphosphate, which recruits and From the ‡UMR5239

A Physical Interaction Network of Dengue Virus and Human Proteins

“…Thus, the results from our initial siRNA experiments strongly suggest our DENV-human interactome is enriched in proteins relevant to DENV infection. Consistent with this conclusion, 57% of our interactions were confirmed in the split-luciferase assay, which is comparable to other high quality yeast two-hybrid studies (75)(76)(77).…”

“…Thirteen pairs (57%) yielded a significant increase in luciferase activity relative to both empty vector controls (p value Ͻ 0.02); we consider this set to represent true positives in the split-luciferase assay. This rate of confirmation is similar to those observed for other high quality large-scale yeast two-hybrid screens, which range from 20 to 85% (22,(75)(76)(77).…”

2640 – Exploring the pathogenetic association between schizophrenia and type 2 diabetes mellitus diseases based on pathway analysis

“…As a result, we found that 59 candidate genes have been connected to SCZ [34][35][36][37][38], 77 candidate genes have been linked to T2D [39][40][41][42][43], while 25 candidate genes [44][45][46][47][48][49] have been implicated to both SCZ and T2D with various studies (Additional file 5). Totally, 161 candidate genes (~45% of all candidate genes) have been related to either SCZ or T2D or both diseases with various experimental approaches, further proving the rationale of "function association" in the application of disease related gene inference.…”

Ckip-1 Regulates Mammalian and Zebrafish Myoblast Fusion

“…To elucidate the mechanism of action of CKIP-1 in cell fusion, a yeast two hybrids screen was performed to identify new CKIP-1 interactors (Pilot-Storck et al, 2010). The Arp2/3 subunit ARPC1A was identified as a direct binding partner for CKIP-1 (Fig.…”

“…We examined muscle fibre formation in Ckip-1 antisense morpholino oligonucleotide injected zebrafish embryos and show that Ckip-1 knock down in zebrafish embryo impairs fast-twitch myoblast fusion. Search for CKIP-1 binding partners (Pilot-Storck et al, 2010) identified ARPC1A subunit of Arp2/3 actin nucleation complex. We demonstrate that CKIP-1 regulates cell morphology and lamellipodia formation through membrane recruitment of Arp2/3 complex.…”