Weibel-Palade bodies recruit Rab27 by a content-driven, maturation-dependent mechanism that is independent of cell type

Hannah, Matthew J.; Hume, Alistair N.; Arribas, Mònica; Williams, Richard A.; Hewlett, Lindsay; Seabra, Miguel C.; Cutler, Daniel F.

doi:10.1242/jcs.00711

Cited by 91 publications

(112 citation statements)

References 63 publications

Supporting

Mentioning

102

Contrasting

Unclassified

Order By: Relevance

“…Cells were rinsed with PBS and lysed in 2ϫ sample buffer 12 containing ␤-mercaptoethanol and protease inhibitors (Sigma-Aldrich: P8340) or in PBS containing 1% Triton X-114, 2mM EDTA, and protease inhibitors. To concentrate hydrophobic proteins, Triton X-114 partitioning of the lysate was performed as described.…”

Section: Immunoblottingmentioning

confidence: 99%

“…To concentrate hydrophobic proteins, Triton X-114 partitioning of the lysate was performed as described. 12 Protein in the detergent phase was precipitated with methanol-chloroform using 0.25 g BSA as carrier. Proteins were separated on a 12% SDS-PAGE gel, transferred to 0.2 m nitrocellulose membrane, and probed with primary Ab, followed by infrared dye-coupled secondaries.…”

Section: Immunoblottingmentioning

confidence: 99%

“…This raises the possibility that the fractions of WPB-Rab27A molecules occupied by MyRIP and Slp4-a are the crucial factor in determining P r . Most newly formed WPBs lack endogenous Slp4-a-IR, MyRIP-IR (Figure 6Dii), Rab27A-IR 12 (and Rab3B-IR, Figure 2B), and for these organelles P r was very low (Figure 6Diii). The close correlation between the increase in P r (Figure 6Diii) and increase in the fraction of WPBs with detectable Slp4-a-and MyRIP-IR (Figure 6Dii) shows that the capacity to undergo exocytosis is closely linked to acquisition of both effector molecules.…”

Section: Rab27a Effectors and Vwf Secretion 2765mentioning

confidence: 99%

“…Human ECs are reported to express mRNA for Rab3A, Rab3D, and Rab37, 3,9,10 Rab3B protein, 11 and Rab27A mRNA and protein. 12,13 To date, Rab27A is the only endogenous EC Rab protein that has been detected on WPBs. Through its effector MyRIP and Myosin Va, Rab27A is proposed to negatively regulate WPB exocytosis.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

The interplay between the Rab27A effectors Slp4-a and MyRIP controls hormone-evoked Weibel-Palade body exocytosis

Bierings

Hellen

Kiskin

et al. 2012

Blood

Self Cite

166

View full text Add to dashboard Cite

Weibel-Palade body (WPB) exocytosis underlies hormone-evoked VWF secretion from endothelial cells (ECs). We identify new endogenous components of the WPB: Rab3B, Rab3D, and the Rab27A/ Rab3 effector Slp4-a (granuphilin), and determine their role in WPB exocytosis. We show that Rab3B, Rab3D, and Rab27A contribute to Slp4-a localization to WPBs. siRNA knockdown of Slp4-a, MyRIP, Rab3B, Rab3D, Rab27A, or Rab3B/ Rab27A, or overexpression of EGFPSlp4-a or EGFP-MyRIP showed that Slp4-a is a positive and MyRIP a negative regulator of WPB exocytosis and that Rab27A alone mediates these effects. We found that ECs maintain a constant amount of cellular Rab27A irrespective of the WPB pool size and that Rab27A (and Rab3s) cycle between WPBs and a cytosolic pool. The dynamic redistribution of Rab proteins markedly decreased the Rab27A concentration on individual WPBs with increasing WPB number per cell. Despite this, the probability of WPB release was independent of WPB pool size showing that WPB exocytosis is not determined simply by the absolute amount of Rab27A and its effectors on WPBs. Instead, we propose that the probability of release is determined by the fractional occupancy of WPB-Rab27A by Slp4-a and MyRIP, with the balance favoring exocytosis. (Blood. 2012;120(13):2757-2767) IntroductionHormone-evoked VWF secretion from endothelial cells (ECs) is mediated by exocytosis of specialized secretory granules (SGs) called Weibel-Palade bodies (WPBs). 1 WPB exocytosis is triggered by increases in intracellular free Ca 2ϩ or cAMP concentrations, and involves a number of molecular components, including the Nethylmaleimide-sensitive factor, VAMP3, SNAP23, syntaxin 4, RalA, the annexin A2/S100A10 complex, and phospholipase D. [2][3][4][5][6][7] In addition, Rab proteins also regulate WPB exocytosis. A subset of Rab proteins, including Rab3A-3D, Rab27A/B, and Rab37, is associated with SGs in different cell types where they regulate SG biogenesis, trafficking, and exocytosis. 8 Secretory cells often express a mixture of these "secretory" Rabs, which may have overlapping or distinct functions. Human ECs are reported to express mRNA for Rab3A, Rab3D, and Rab37,3,9,10 Rab3B protein, 11 and Rab27A mRNA and protein. 12,13 To date, Rab27A is the only endogenous EC Rab protein that has been detected on WPBs. Through its effector MyRIP and Myosin Va, Rab27A is proposed to negatively regulate WPB exocytosis. 13,14 Rab27A can interact with different effector molecules, and many secretory cells express a mixture of these effectors. 8 In these cases, SG exocytosis probably depends on the balance of Rab27A interactions with the complement of Rab effectors in the cell.In addition to MyRIP, ECs contain mRNA for the Rab27A effector Slp4-a (granuphilin). 13 Slp4-a links SGs to the plasma membrane (PM) through SG-associated Rab proteins (principally Rab27A), PM-associated syntaxins (1a, 2, or 3) and soluble Munc18 isoforms. [15][16][17][18][19] Syntaxins exist in open and closed conformations that determine their participation in SNARE complex f...

show abstract

Section: Immunoblottingmentioning

confidence: 99%

Section: Immunoblottingmentioning

confidence: 99%

Section: Rab27a Effectors and Vwf Secretion 2765mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The interplay between the Rab27A effectors Slp4-a and MyRIP controls hormone-evoked Weibel-Palade body exocytosis

Bierings

Hellen

Kiskin

et al. 2012

Blood

Self Cite

166

View full text Add to dashboard Cite

show abstract

“…149). The association of myosin V 106,127 , RAB27a 150 , or both 151 with other types of exocytic granule hints at a myosin-scaffolding protein-RAB27 machinery that drives the late steps of exocytosis in many instances.…”

Section: Box 3 | Coordinating Several Motors: the Melanosome Paradigmmentioning

confidence: 99%

Powering membrane traffic in endocytosis and recycling

Soldati

Schliwa

2006

Nat Rev Mol Cell Biol

311

279

View full text Add to dashboard Cite

| Early in evolution, the diversification of membrane-bound compartments that characterize eukaryotic cells was accompanied by the elaboration of molecular machineries that mediate intercompartmental communication and deliver materials to specific destinations. Molecular motors that move on tracks of actin filaments or microtubules mediate the movement of organelles and transport between compartments. The subjects of this review are the motors that power the transport steps along the endocytic and recycling pathways, their modes of attachment to cargo and their regulation.The emergence of eukaryotic cells was accompanied by the development of endomembrane systems that compartmentalize biochemical pathways and biosynthetic processes. An evolutionary trend towards increasing complexity and subcellular specialization necessitated the development of machineries for intercompartmental communication. Molecular assemblies evolved to confer specificity to the interactions of donor and acceptor compartments (budding, sorting, tethering and fusion). Cytoskeletal polymers such as actin filaments and microtubules, which help segregate genetic material and determine cell shape and subcellular architecture, were co-opted as tracks for transport. In animal cells, microtubules support long-range transport, whereas the more flexible actin filaments serve short-range movements both near the cell periphery and in the cell interior. Also, actin filaments can be woven into dense networks of short fibres through the action of crosslinkers and branchpromoting complexes. On the other hand, in many plant cells, bundled actin filaments can form extended tracks for long-distance transport. Owing to the gel-like nature of the cytoplasm, the Brownian movement of organelles is severely restricted and cargoes have to be transported to their destinations at the expense of energy. Furthermore, seemingly random, but motor-dependent, movement is proposed to increase the probability of vesicle collisions and therefore promote fusion events. Movement is powered by three ATP-dependent motors: myosin, kinesin and dynein. Over the course of eukaryotic evolution, these motors have diversified into a large number of families with specific tasks (FIG. 1).Here, we review the involvement of molecular motors in the movement of endosomes and in vesicular trafficking along the endocytic and recycling pathways. These pathways are summarized in FIG. 2. We do not, however,

show abstract

Lysosome‐Related Organelles: Modifications of the Lysosome Paradigm

Mantegazza

Marks

2016

Lysosomes: Biology, Diseases, and Therapeutics

View full text Add to dashboard Cite

Weibel-Palade bodies recruit Rab27 by a content-driven, maturation-dependent mechanism that is independent of cell type

Cited by 91 publications

References 63 publications

The interplay between the Rab27A effectors Slp4-a and MyRIP controls hormone-evoked Weibel-Palade body exocytosis

The interplay between the Rab27A effectors Slp4-a and MyRIP controls hormone-evoked Weibel-Palade body exocytosis

Powering membrane traffic in endocytosis and recycling

Lysosome‐Related Organelles: Modifications of the Lysosome Paradigm

Contact Info

Product

Resources

About