Cooperation of MICAL-L1, syndapin2, and phosphatidic acid in tubular recycling endosome biogenesis

Endocytic transport necessitates the generation of membrane tubules and their subsequent fission to transport vesicles for sorting of cargo molecules. The endocytic recycling compartment, an array of tubular and vesicular membranes decorated by the Eps15 homology domain protein, EHD1, is responsible for receptor and lipid recycling to the plasma membrane. It has been proposed that EHD dimers bind and bend membranes, thus generating recycling endosome (RE) tubules. However, recent studies show that molecules interacting with CasL-Like1 (MICAL-L1), a second, recently identified RE tubule marker, recruits EHD1 to preexisting tubules. The mechanisms and events supporting the generation of tubular recycling endosomes were unclear. Here, we propose a mechanism for the biogenesis of RE tubules. We demonstrate that MICAL-L1 and the BAR-domain protein syndapin2 bind to phosphatidic acid, which we identify as a novel lipid component of RE. Our studies demonstrate that direct interactions between these two proteins stabilize their association with membranes, allowing for nucleation of tubules by syndapin2. Indeed, the presence of phosphatidic acid in liposomes enhances the ability of syndapin2 to tubulate membranes in vitro. Overall our results highlight a new role for phosphatidic acid in endocytic recycling and provide new insights into the mechanisms by which tubular REs are generated.

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Syndapin/SDPN-1 is required for endocytic recycling and endosomal actin association in the Caenorhabditis elegans intestine

Molecular Biology of the Cell ◽

10.1091/mbc.e16-02-0116 ◽

2016 ◽

Vol 27 (23) ◽

pp. 3746-3756 ◽

Cited By ~ 7

Author(s):

Adenrele M. Gleason ◽

Ken C. Q. Nguyen ◽

David H. Hall ◽

Barth D. Grant

Keyword(s):

Caenorhabditis Elegans ◽

Membrane Lipids ◽

Actin Dynamics ◽

Endocytic Recycling ◽

Recycling Endosome ◽

Recycling Endosomes ◽

Bar Domain ◽

C Elegans ◽

Early Endosomes

Syndapin/pascin-family F-BAR domain proteins bind directly to membrane lipids and are associated with actin dynamics at the plasma membrane. Previous reports also implicated mammalian syndapin 2 in endosome function during receptor recycling, but precise analysis of a putative recycling function for syndapin in mammalian systems is difficult because of its effects on the earlier step of endocytic uptake and potential redundancy among the three separate genes that encode mammalian syndapin isoforms. Here we analyze the endocytic transport function of the only Caenorhabditis elegans syndapin, SDPN-1. We find that SDPN-1 is a resident protein of the early and basolateral recycling endosomes in the C. elegans intestinal epithelium, and sdpn-1 deletion mutants display phenotypes indicating a block in basolateral recycling transport. sdpn-1 mutants accumulate abnormal endosomes positive for early endosome and recycling endosome markers that are normally separate, and such endosomes accumulate high levels of basolateral recycling cargo. Furthermore, we observed strong colocalization of endosomal SDPN-1 with the F-actin biosensor Lifeact and found that loss of SDPN-1 greatly reduced Lifeact accumulation on early endosomes. Taken together, our results provide strong evidence for an in vivo function of syndapin in endocytic recycling and suggest that syndapin promotes transport via endosomal fission.

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Arf GTPase-activating Protein ASAP1 Interacts with Rab11 Effector FIP3 and Regulates Pericentrosomal Localization of Transferrin Receptor–positive Recycling Endosome

Molecular Biology of the Cell ◽

10.1091/mbc.e08-03-0290 ◽

2008 ◽

Vol 19 (10) ◽

pp. 4224-4237 ◽

Cited By ~ 53

Author(s):

Hiroki Inoue ◽

Vi Luan Ha ◽

Rytis Prekeris ◽

Paul A. Randazzo

Keyword(s):

Membrane Trafficking ◽

Transferrin Receptor ◽

Endocytic Recycling ◽

Recycling Endosome ◽

Bar Domain ◽

Gtpase Activating Proteins ◽

Membrane Tubulation ◽

Interfering Rna ◽

Hybrid Screening

ADP-ribosylation factors (Arfs) and Arf GTPase-activating proteins (GAPs) are key regulators of membrane trafficking and the actin cytoskeleton. The Arf GAP ASAP1 contains an N-terminal BAR domain, which can induce membrane tubulation. Here, we report that the BAR domain of ASAP1 can also function as a protein binding site. Two-hybrid screening identified FIP3, which is a putative Arf6- and Rab11-effector, as a candidate ASAP1 BAR domain-binding protein. Both coimmunoprecipitation and in vitro pulldown assays confirmed that ASAP1 directly binds to FIP3 through its BAR domain. ASAP1 formed a ternary complex with Rab11 through FIP3. FIP3 binding to the BAR domain stimulated ASAP1 GAP activity against Arf1, but not Arf6. ASAP1 colocalized with FIP3 in the pericentrosomal endocytic recycling compartment. Depletion of ASAP1 or FIP3 by small interfering RNA changed the localization of transferrin receptor, which is a marker of the recycling endosome, in HeLa cells. The depletion also altered the trafficking of endocytosed transferrin. These results support the conclusion that ASAP1, like FIP3, functions as a component of the endocytic recycling compartment.

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FAM92A1 is a BAR domain protein required for mitochondrial ultrastructure and function

The Journal of Cell Biology ◽

10.1083/jcb.201806191 ◽

2018 ◽

Vol 218 (1) ◽

pp. 97-111 ◽

Cited By ~ 7

Author(s):

Liang Wang ◽

Ziyi Yan ◽

Helena Vihinen ◽

Ove Eriksson ◽

Weihuan Wang ◽

...

Keyword(s):

Mitochondrial Function ◽

Molecular Mechanisms ◽

Membrane Curvature ◽

Mitochondrial Morphology ◽

Membrane Remodeling ◽

Mitochondrial Ultrastructure ◽

Bar Domain ◽

Bar Domain Proteins ◽

Domain Protein

Mitochondrial function is closely linked to its dynamic membrane ultrastructure. The mitochondrial inner membrane (MIM) can form extensive membrane invaginations known as cristae, which contain the respiratory chain and ATP synthase for oxidative phosphorylation. The molecular mechanisms regulating mitochondrial ultrastructure remain poorly understood. The Bin-Amphiphysin-Rvs (BAR) domain proteins are central regulators of diverse cellular processes related to membrane remodeling and dynamics. Whether BAR domain proteins are involved in sculpting membranes in specific submitochondrial compartments is largely unknown. In this study, we report FAM92A1 as a novel BAR domain protein localizes to the matrix side of the MIM. Loss of FAM92A1 caused a severe disruption to mitochondrial morphology and ultrastructure, impairing organelle bioenergetics. Furthermore, FAM92A1 displayed a membrane-remodeling activity in vitro, inducing a high degree of membrane curvature. Collectively, our findings uncover a role for a BAR domain protein as a critical organizer of the mitochondrial ultrastructure that is indispensable for mitochondrial function.

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Specialized sorting of GLUT4 and its recruitment to the cell surface are independently regulated by distinct Rabs

Molecular Biology of the Cell ◽

10.1091/mbc.e13-02-0103 ◽

2013 ◽

Vol 24 (16) ◽

pp. 2544-2557 ◽

Cited By ~ 51

Author(s):

L. Amanda Sadacca ◽

Joanne Bruno ◽

Jennifer Wen ◽

Wenyong Xiong ◽

Timothy E. McGraw

Keyword(s):

Plasma Membrane ◽

Glucose Uptake ◽

Glucose Transporter ◽

Receptor Activation ◽

Glut4 Translocation ◽

Insulin Stimulation ◽

Transport Vesicles ◽

Glucose Transporter Glut4

Adipocyte glucose uptake in response to insulin is essential for physiological glucose homeostasis: stimulation of adipocytes with insulin results in insertion of the glucose transporter GLUT4 into the plasma membrane and subsequent glucose uptake. Here we establish that RAB10 and RAB14 are key regulators of GLUT4 trafficking that function at independent, sequential steps of GLUT4 translocation. RAB14 functions upstream of RAB10 in the sorting of GLUT4 to the specialized transport vesicles that ferry GLUT4 to the plasma membrane. RAB10 and its GTPase-activating protein (GAP) AS160 comprise the principal signaling module downstream of insulin receptor activation that regulates the accumulation of GLUT4 transport vesicles at the plasma membrane. Although both RAB10 and RAB14 are regulated by the GAP activity of AS160 in vitro, only RAB10 is under the control of AS160 in vivo. Insulin regulation of the pool of RAB10 required for GLUT4 translocation occurs through regulation of AS160, since activation of RAB10 by DENND4C, its GTP exchange factor, does not require insulin stimulation.

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Amino acid permeases require COPII components and the ER resident membrane protein Shr3p for packaging into transport vesicles in vitro.

The Journal of Cell Biology ◽

10.1083/jcb.135.3.585 ◽

1996 ◽

Vol 135 (3) ◽

pp. 585-595 ◽

Cited By ~ 90

Author(s):

M J Kuehn ◽

R Schekman ◽

P O Ljungdahl

Keyword(s):

Plasma Membrane ◽

Amino Acid ◽

Membrane Protein ◽

Integral Membrane Protein ◽

Plasma Membrane Atpase ◽

Amino Acid Permease ◽

Transport Vesicles ◽

Amino Acid Permeases ◽

Histidine Permease

In S. cerevisiae lacking SHR3, amino acid permeases specifically accumulate in membranes of the endoplasmic reticulum (ER) and fail to be transported to the plasma membrane. We examined the requirements of transport of the permeases from the ER to the Golgi in vitro. Addition of soluble COPII components (Sec23/24p, Sec13/31p, and Sar1p) to yeast membrane preparations generated vesicles containing the general amino acid permease. Gap1p, and the histidine permease, Hip1p. Shr3p was required for the packaging of Gap1p and Hip1p but was not itself incorporated into transport vesicles. In contrast, the packaging of the plasma membrane ATPase, Pma1p, and the soluble yeast pheromone precursor, glycosylated pro alpha factor, was independent of Shr3p. In addition, we show that integral membrane and soluble cargo colocalize in transport vesicles, indicating that different types of cargo are not segregated at an early step in secretion. Our data suggest that specific ancillary proteins in the ER membrane recruit subsets of integral membrane protein cargo into COPII transport vesicles.

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Annexin XIIIb: a novel epithelial specific annexin is implicated in vesicular traffic to the apical plasma membrane.

The Journal of Cell Biology ◽

10.1083/jcb.128.6.1043 ◽

1995 ◽

Vol 128 (6) ◽

pp. 1043-1053 ◽

Cited By ~ 104

Author(s):

K Fiedler ◽

F Lafont ◽

R G Parton ◽

K Simons

Keyword(s):

Plasma Membrane ◽

Cell Surface ◽

Mdck Cells ◽

Apical Cell ◽

Protein Composition ◽

Apical Plasma Membrane ◽

Vesicular Traffic ◽

Transport Vesicles ◽

Apical Vesicles

The sorting of apical and basolateral proteins into vesicular carriers takes place in the trans-Golgi network (TGN) in MDCK cells. We have previously analyzed the protein composition of immunoisolated apical and basolateral transport vesicles and have now identified a component that is highly enriched in apical vesicles. Isolation of the encoding cDNA revealed that this protein, annexin XIIIb, is a new isoform of the epithelial specific annexin XIII sub-family which includes the previously described intestine-specific annexin (annexin XIIIa; Wice, B. M., and J. I. Gordon. 1992. J. Cell Biol. 116:405-422). Annexin XIIIb differs from annexin XIIIa in that it contains a unique insert of 41 amino acids in the NH2 terminus and is exclusively expressed in dog intestine and kidney. Immunofluorescence microscopy demonstrated that annexin XIIIb was localized to the apical plasma membrane and underlying punctate structures. Since annexins have been suggested to play a role in membrane-membrane interactions in exocytosis and endocytosis, we investigated whether annexin XIIIb is involved in delivery to the apical cell surface. To this aim we used permeabilized MDCK cells and a cytosol-dependent in vitro transport assay. Antibodies specific for annexin XIIIb significantly inhibited the transport of influenza virus hemagglutinin from the TGN to the apical plasma membrane while the transport of vesicular stomatitis virus glycoprotein to the basolateral cell surface was unaffected. We propose that annexin XIIIb plays a role in vesicular transport to the apical plasma membrane in MDCK cells.

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MICAL-L1 Links EHD1 to Tubular Recycling Endosomes and Regulates Receptor Recycling

Molecular Biology of the Cell ◽

10.1091/mbc.e09-06-0535 ◽

2009 ◽

Vol 20 (24) ◽

pp. 5181-5194 ◽

Cited By ~ 103

Author(s):

Mahak Sharma ◽

Sai Srinivas Panapakkam Giridharan ◽

Juliati Rahajeng ◽

Naava Naslavsky ◽

Steve Caplan

Keyword(s):

Coiled Coil ◽

Live Cells ◽

Endocytic Recycling ◽

Interacting Protein ◽

Recycling Endosomes ◽

Coiled Coil Region ◽

Membrane Tubules ◽

Tubular Membranes

Endocytic recycling of receptors and lipids occurs via a complex network of tubular and vesicular membranes. EHD1 is a key regulator of endocytosis and associates with tubular membranes to facilitate recycling. Although EHD proteins tubulate membranes in vitro, EHD1 primarily associates with preexisting tubules in vivo. How EHD1 is recruited to these tubular endosomes remains unclear. We have determined that the Rab8-interacting protein, MICAL-L1, associates with EHD1, with both proteins colocalizing to long tubular membranes, in vitro and in live cells. MICAL-L1 is a largely uncharacterized member of the MICAL-family of proteins that uniquely contains two asparagine-proline-phenylalanine motifs, sequences that typically interact with EH-domains. Our data show that the MICAL-L1 C-terminal coiled-coil region is necessary and sufficient for its localization to tubular membranes. Moreover, we provide unexpected evidence that endogenous MICAL-L1 can link both EHD1 and Rab8a to these structures, as its depletion leads to loss of the EHD1-Rab8a interaction and the absence of both of these proteins from the membrane tubules. Finally, we demonstrate that MICAL-L1 is essential for efficient endocytic recycling. These data implicate MICAL-L1 as an unusual type of Rab effector that regulates endocytic recycling by recruiting and linking EHD1 and Rab8a on membrane tubules.

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Tip growth in the brown alga Ectocarpus is controlled by a RHO-GAP-BAR domain protein independently from F-actin organisation

10.1101/2021.08.28.458042 ◽

2021 ◽

Author(s):

Zofia Nehr ◽

Sabine Chenivesse ◽

Bernard Billoud ◽

Sabine Genicot ◽

Nathalie Desban ◽

...

Keyword(s):

Plasma Membrane ◽

Brown Alga ◽

Tip Growth ◽

Apical Cell ◽

Null Mutation ◽

Rt Pcr ◽

Bar Domain ◽

Independent Mechanism ◽

Domain Protein

The brown alga Ectocarpus is a filamentous seaweed that grows by tip growth and branching. In the morphometric mutant etoile, tip growth is slower than in the WT and eventually stops. In this paper, we show that the causal etoile mutation is a null mutation in a bi-domain BAR-RhoGAP gene. By quantitative RT-PCR, we showed that ETOILE is ubiquitously expressed in prostrate filaments of the Ectocarpus sporophyte, and is downregulated in the etoile mutant. We immunolocalised both domains of the protein in WT and etoile, as well as RAC1, the known target of Rho-GAP enzymes. Thus, ETOILE would be localised at the apical cell dome where it would control the localisation of EsRAC1 to the plasma membrane. Actin staining showed that the mutant is not affected in F-actin structures. Overall, these results suggest that in Ectocarpus, BAR-RhoGAP controls tip growth by controlling RAC1 localization and through an actin-independent mechanism.

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VAMP8-dependent fusion of recycling endosomes with the plasma membrane facilitates T lymphocyte cytotoxicity

The Journal of Cell Biology ◽

10.1083/jcb.201411093 ◽

2015 ◽

Vol 210 (1) ◽

pp. 135-151 ◽

Cited By ~ 48

Author(s):

Misty R. Marshall ◽

Varsha Pattu ◽

Mahantappa Halimani ◽

Monika Maier-Peuschel ◽

Martha-Lena Müller ◽

...

Keyword(s):

Plasma Membrane ◽

Cell Types ◽

Snare Proteins ◽

Recycling Endosome ◽

Granule Exocytosis ◽

Recycling Endosomes ◽

Immune Synapses ◽

Lymphocyte Cytotoxicity ◽

Cytotoxic Granule

Cytotoxic T lymphocytes (CTLs) eliminate infected and neoplastic cells through directed release of cytotoxic granule contents. Although multiple SNARE proteins have been implicated in cytotoxic granule exocytosis, the role of vesicular SNARE proteins, i.e., vesicle-associated membrane proteins (VAMPs), remains enigmatic. VAMP8 was posited to represent the cytotoxic granule vesicular SNARE protein mediating exocytosis in mice. In primary human CTLs, however, VAMP8 colocalized with Rab11a-positive recycling endosomes. Upon stimulation, these endosomes rapidly trafficked to and fused with the plasma membrane, preceding fusion of cytotoxic granules. Knockdown of VAMP8 blocked both recycling endosome and cytotoxic granule fusion at immune synapses, without affecting activating signaling. Mechanistically, VAMP8-dependent recycling endosomes deposited syntaxin-11 at immune synapses, facilitating assembly of plasma membrane SNARE complexes for cytotoxic granule fusion. Hence, cytotoxic granule exocytosis is a sequential, multivesicle fusion process requiring VAMP8-mediated recycling endosome fusion before cytotoxic granule fusion. Our findings imply that secretory granule exocytosis pathways in other cell types may also be more complex than previously appreciated.

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The Simultaneous Production of Phosphatidic Acid and Diacylglycerol Is Essential for the Translocation of Protein Kinase Cϵ to the Plasma Membrane in RBL-2H3 Cells

Molecular Biology of the Cell ◽

10.1091/mbc.e03-05-0295 ◽

2003 ◽

Vol 14 (12) ◽

pp. 4885-4895 ◽

Cited By ~ 64

Author(s):

Maria Jose Lopez-Andreo ◽

Juan C. Gomez-Fernandez ◽

Senena Corbalan-Garcia

Keyword(s):

Plasma Membrane ◽

Protein Kinase ◽

Phosphatidic Acid ◽

Enzyme Activation ◽

C2 Domain ◽

Direct Stimulation ◽

Downstream Target ◽

Low Concentrations ◽

Stimulation Of

To evaluate the role of the C2 domain in protein kinase Cϵ (PKCϵ) localization and activation after stimulation of the IgE receptor in RBL-2H3 cells, we used a series of mutants located in the phospholipid binding region of the enzyme. The results obtained suggest that the interaction of the C2 domain with the phospholipids in the plasma membrane is essential for anchoring the enzyme in this cellular compartment. Furthermore, the use of specific inhibitors of the different pathways that generate both diacylglycerol and phosphatidic acid has shown that the phosphatidic acid generated via phospholipase D (PLD)-dependent pathway, in addition to the diacylglycerol generated via phosphoinosite-phospholipase C (PLC), are involved in the localization of PKCϵ in the plasma membrane. Direct stimulation of RBL-2H3 cells with very low concentrations of permeable phosphatidic acid and diacylglycerol exerted a synergistic effect on the plasma membrane localization of PKCϵ. Moreover, the in vitro kinase assays showed that both phosphatidic acid and diacylglycerol are essential for enzyme activation. Together, these results demonstrate that phosphatidic acid is an important and essential activator of PKCϵ through the C2 domain and locate this isoenzyme in a new scenario where it acts as a downstream target of PLD.

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