Disease relevance of MAGI3

• In glioblastoma SF763T cells MAGI-3 was associated with a tyrosine-phosphorylated protein with the apparent molecular weight of 130 kDa, whereas in Caco2 cells it was associated with a 90 kDa protein [1].
• In the present work, we demonstrate the specific interaction between LPA(2) and MAGI-3, and the effects of MAGI-3 in colon cancer cells using SW480 as a cell model [2].

High impact information on MAGI3

• Moreover, two novel beta1AR-interacting proteins, SAP97 and MAGI-3, were also identified [3].
• Full-length beta1AR robustly associated with full-length MAGI-3 in cells, and this association was abolished by mutation of the beta1AR terminal valine residue to alanine (V477A), as determined by co-immunoprecipitation experiments and immunofluorescence co-localization studies [3].
• MAGI-3 co-expression with beta1AR profoundly impaired beta1AR-mediated ERK1/2 activation but had no apparent effect on beta1AR-mediated cyclic AMP generation or agonist-promoted beta1AR internalization [3].
• These data suggest that MAGI3 allows for the juxtaposition of PTEN/MMAC to phospholipid signaling pathways involved with cell survival [4].
• In this study, we show that a multi-PDZ containing protein, MAGI-3, specifically binds to frizzled-4 and -7 [5].

Anatomical context of MAGI3

• Here we show that two of the three known MAGI isoforms, MAGI-1 and MAGI-3, are present in the tight junctions of cultured epithelial cells [6].
• These findings suggest a possible role for MAGI-3 as a scaffolding molecule that links receptor tyrosine phosphatase with its substrates at the plasma membrane [1].
• In epithelial cells, MAGI-3 was localized with ZO-1 and cingulin at tight junctions, whereas in primary cultured astrocytes it was found in E-cadherin-based cell-cell contacts and in focal adhesion sites [1].
• Immunolocalization showed that MAGI-3 and TGFalpha were colocalized in neurons in the cortex and dentate gyrus, as well as in ependymal cells and some astrocytes [7].
• Human T-cell leukemia virus type 1 Tax oncoprotein induces and interacts with a multi-PDZ domain protein, MAGI-3 [8].

Associations of MAGI3 with chemical compounds

• Although MAGI-3 itself was not phosphorylated on tyrosine residues, it became associated with tyrosine-phosphorylated proteins following a short treatment of the cells with vanadate [1].

Physical interactions of MAGI3

• Junctional protein MAGI-3 interacts with receptor tyrosine phosphatase beta (RPTP beta) and tyrosine-phosphorylated proteins [1].

Regulatory relationships of MAGI3

• These results demonstrate that MAGI-3 interacts directly with LPA(2) and regulates the ability of LPA(2) to activate Erk and RhoA [2].

Other interactions of MAGI3

• Oncogenic human papillomavirus E6 proteins target the MAGI-2 and MAGI-3 proteins for degradation [9].
• The interaction between RPTP beta and MAGI-3 was confirmed by co-immunoprecipitation and pulldown experiments in transfected cells [1].
• The 10a scaffold inhibited the interaction between MAGI-3 and PTEN and showed cellular activities that are consistent with the inhibition of NHERF-1 function [10].

Analytical, diagnostic and therapeutic context of MAGI3

• Immunofluorescence and immunoelectron microscopy revealed that MAGI-3 is concentrated in specific sites at the plasma membrane and in the nucleus [1].
• Reverse transcription-polymerase chain reaction (RT-PCR) analysis confirmed that Tax1 induced MAGI-3 in Rat-1 cells [8].

References