Direct interaction between ER membrane-bound PTP1B and its plasma membrane-anchored targets

Anderie, Ines; Schulz, Irene; Schmid, Andreas

doi:10.1016/j.cellsig.2006.08.007

Cited by 80 publications

(60 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…BiFC and FRET studies also have observed PTP1BDA/substrate complexes as fluorescent clusters (Haj et al, 2002;Anderie et al, 2007;Nievergall et al, 2010;Monteleone et al, 2012). In the present study the BiFC signal for YN-PTP1BDA/a-actinin-YC were also observed as puncta in more peripheral adhesions.…”

Section: Ptp1b Promotes Lamellar Protrusion Persistence and Directionsupporting

confidence: 58%

PTP1B promotes focal complex maturation, lamellar persistence and directional migration

Burdisso

González

Arregui

2013

Journal of Cell Science

View full text Add to dashboard Cite

SummaryPrevious findings established that ER-bound PTP1B targets peripheral cell-matrix adhesions and positively regulates cell adhesion to fibronectin. Here we show that PTP1B enhances focal complex lifetime at the lamellipodium base, delaying their turnover and facilitating a-actinin incorporation. We demonstrate the presence of catalytic PTP1BD181A-a-actinin complexes at focal complexes. Kymograph analysis revealed that PTP1B contributes to lamellar protrusion persistence and directional cell migration. Pull-down and FRET analysis also showed that PTP1B is required for efficient integrin-dependent downregulation of RhoA and upregulation of Rac1 during spreading. A substrate trap strategy revealed that FAK/Src recruitment and Src activity are essential for the generation of PTP1B substrates in adhesions. PTP1B targets the negative regulatory site of Src (phosphotyrosine 529), paxillin and p130Cas at peripheral cell-matrix adhesions. We postulate that PTP1B modulates more than one pathway required for focal complex maturation and membrane protrusion, including aactinin-mediated cytoskeletal anchorage, integrin-dependent activation of the FAK/Src signaling pathway, and RhoA and Rac1 GTPase activity. By doing so, PTP1B contributes to coordinated adhesion turnover, lamellar stability and directional cell migration.

show abstract

Section: Ptp1b Promotes Lamellar Protrusion Persistence and Directionsupporting

confidence: 58%

PTP1B promotes focal complex maturation, lamellar persistence and directional migration

Burdisso

González

Arregui

2013

Journal of Cell Science

View full text Add to dashboard Cite

show abstract

“…However, highly specific interactions between membrane proteins have been demonstrated using this technique in other systems (26)(27)(28). Also, the absence of an interaction with the plasma membrane protein PIP2-1 makes this possibility unlikely.…”

Section: Discussionmentioning

confidence: 99%

Organization of cellulose synthase complexes involved in primary cell wall synthesis in Arabidopsis thaliana

Desprez

Juraniec

Crowell

et al. 2007

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

532

605

View full text Add to dashboard Cite

In all land plants, cellulose is synthesized from hexameric plasma membrane complexes. Indirect evidence suggests that in vascular plants the complexes involved in primary wall synthesis contain three distinct cellulose synthase catalytic subunits (CESAs). In this study, we show that CESA3 and CESA6 fused to GFP are expressed in the same cells and at the same time in the hypocotyl of etiolated seedlings and migrate with comparable velocities along linear trajectories at the cell surface. We also show that CESA3 and CESA6 can be coimmunoprecipitated from detergent-solubilized extracts, their protein levels decrease in mutants for either CESA3, CESA6, or CESA1 and CESA3, CESA6 and also CESA1 can physically interact in vivo as shown by bimolecular fluorescence complementation. We also demonstrate that CESA6-related CESA5 and CESA2 are partially, but not completely, redundant with CESA6 and most likely compete with CESA6 for the same position in the cellulose synthesis complex. Using promoter-␤-glucuronidase fusions we show that CESA5, CESA6, and CESA2 have distinct overlapping expression patterns in hypocotyl and root corresponding to different stages of cellular development. Together, these data provide evidence for the existence of binding sites for three distinct CESA subunits in primary wall cellulose synthase complexes, with two positions being invariably occupied by CESA1 and CESA3, whereas at least three isoforms compete for the third position. Participation of the latter three isoforms might fine-tune the CESA complexes for the deposition of microfibrils at distinct cellular growth stages. C ellulose microfibrils are synthesized from a multiprotein complex inserted into the plasma membrane. These ''rosette'' complexes consist of six globules, each of which contains multiple cellulose synthase catalytic subunits (CESAs). These complexes migrate in the plasma membrane along microtubules, propelled by the polymerization of the ␤-1,4-glucan chains (1).Plant CESA genes are members of multigene families. Arabidopsis has 10 CESA isoforms that, based on sequence comparison with other plant species, can be classified into six orthologous groups (2). Mutational analysis shows that these six groups of isoforms have nonredundant functions in cellulose synthesis. Mutants for three isoforms (CESA4, CESA7, and CESA8) show defects in cellulose synthesis specifically in secondary walls (3)(4)(5). Microarray data show that the mRNAs for the three genes are coregulated (6, 7). The three proteins are expressed in the same cell types during secondary cell wall deposition, and co-immunoprecipitation (IP) experiments show that all three proteins interact (3). Although the interactions remain to be validated in vivo, these data strongly suggest that at least in these cells the complexes contain three isoforms. Mutants for isoforms CESA1, CESA3, and CESA6 have cellulose defects in primary cell walls (8-11). The three genes are also coregulated at the mRNA level (12). It is not known, however, whether the corresponding proteins are ...

show abstract

“…In SOCE, upon depletion of Ca 2+ in the ER, the ER protein stromal interaction molecule 1 (STIM1) oligomerizes, binds, and activates Orai1 Ca 2+ channels at the PM to drive influx of extracellular Ca 2+ , thereby allowing homeostatic regulation of ER Ca 2+ levels (3,4). However, growing evidence suggests that ER-PM contacts also play more general roles, including signaling (5,6) and the regulation of both lipid metabolism and transport between bilayers (1,(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17).…”

mentioning

confidence: 99%

Three-dimensional architecture of extended synaptotagmin-mediated endoplasmic reticulum–plasma membrane contact sites

Fernández-Busnadiego

Saheki

Camilli

2015

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

204

251

View full text Add to dashboard Cite

The close apposition between the endoplasmic reticulum (ER) and the plasma membrane (PM) plays important roles in Ca 2+ homeostasis, signaling, and lipid metabolism. The extended synaptotagmins (E-Syts; tricalbins in yeast) are ER-anchored proteins that mediate the tethering of the ER to the PM and are thought to mediate lipid transfer between the two membranes. E-Syt cytoplasmic domains comprise a synaptotagmin-like mitochondrial-lipidbinding protein (SMP) domain followed by five C2 domains in E-Syt1 and three C2 domains in E-Syt2/3. Here, we used cryo-electron tomography to study the 3D architecture of E-Syt-mediated ER-PM contacts at molecular resolution. In vitrified frozen-hydrated mammalian cells overexpressing individual E-Syts, in which E-Sytdependent contacts were by far the predominant contacts, ER-PM distance (19-22 nm) correlated with the amino acid length of the cytosolic region of E-Syts (i.e., the number of C2 domains). Elevation of cytosolic Ca 2+ shortened the ER-PM distance at E-Syt1-dependent contacts sites. E-Syt-mediated contacts displayed a characteristic electron-dense layer between the ER and the PM. These features were strikingly different from those observed in cells exposed to conditions that induce contacts mediated by the stromal interaction molecule 1 (STIM1) and the Ca 2+ channel Orai1 as well as store operated Ca 2+ entry. In these cells the gap between the ER and the PM was spanned by filamentous structures perpendicular to the membranes. Our results define specific ultrastructural features of E-Syt-dependent ER-PM contacts and reveal their structural plasticity, which may impact on the cross-talk between the ER and the PM and the functions of E-Syts in lipid transport between the two bilayers.T he endoplasmic reticulum (ER) consists of a complex network of tubules and cisternae that extends throughout the cell and forms close appositions ("contact sites") with other membranous organelles and with the plasma membrane (PM) (1, 2). The best characterized function of ER-PM contacts is in Ca 2+ homeostasis, as ER-PM contacts mediate the excitationcontraction coupling in muscle and store-operated Ca 2+ entry (SOCE) in all metazoan cells. In SOCE, upon depletion of Ca 2+ in the ER, the ER protein stromal interaction molecule 1 (STIM1) oligomerizes, binds, and activates Orai1 Ca 2+ channels at the PM to drive influx of extracellular Ca 2+ , thereby allowing homeostatic regulation of ER Ca 2+ levels (3, 4). However, growing evidence suggests that ER-PM contacts also play more general roles, including signaling (5, 6) and the regulation of both lipid metabolism and transport between bilayers (1, 7-17).We recently have shown that the three mammalian extended synaptotagmins (E-Syts), homologs of the yeast tricalbins (18,19), act as ER-PM tethers (20). E-Syts are ER-anchored proteins (via an N-terminal hairpin) containing a synaptotagmin-like mitochondrial-lipid-binding protein (SMP) domain followed by five (E-Syt1) or three (E-Syt2/3) C2 domains. SMP domains are present in proteins that loc...

show abstract

Direct interaction between ER membrane-bound PTP1B and its plasma membrane-anchored targets

Cited by 80 publications

References 35 publications

PTP1B promotes focal complex maturation, lamellar persistence and directional migration

PTP1B promotes focal complex maturation, lamellar persistence and directional migration

Organization of cellulose synthase complexes involved in primary cell wall synthesis in Arabidopsis thaliana

Three-dimensional architecture of extended synaptotagmin-mediated endoplasmic reticulum–plasma membrane contact sites

Contact Info

Product

Resources

About