The structure and biogenesis of plant oil bodies: the role of the ER membrane and the oleosin class of proteins

1996 ◽  
Vol 31 (5) ◽  
pp. 945-956 ◽  
Author(s):  
Johnathan A. Napier ◽  
A. Keith Stobart ◽  
Peter R. Shewry
Keyword(s):  
Oil Bodies ◽  
Plant Oil ◽  
Er Membrane

scholarly journals Recent developments and prospects in the composition, extraction, stability, delivery system, digestion and food applications of plant oil bodies

2021 ◽  
Author(s):  
Jia Hao ◽  
Duoxia Xu ◽  
Yangping Cao
Keyword(s):  
Delivery System ◽  
Large Scale ◽  
Protein Identification ◽  
Meat Products ◽  
Calorie Intake ◽  
Oil Bodies ◽  
Plant Oil ◽  
Electrostatic Deposition ◽  
Food Applications ◽  
The Stability

Oil bodies (OBs) are micron- or submicron-sized sub-organelles widely found in plants seeds and nuts. The structure OBs is composed of a core of triglycerides covered by a phospholipid-protein layer, which ensures the stability of the OBs under extreme environmental conditions and further protects core lipids as energy reserves. As naturally pre-emulsified oil-in-water emulsions, OBs have been gradually applied to replace synthetically engineered oil droplets. In this paper, the recent research on the composition, extraction, stability, delivery system, digestion, food applications and future perspectives of plant OBs are reviewed. Recent studies have focused on the OBs surface protein identification and function, large-scale extraction techniques such as enzyme assisted, high pressure, ultrasound, and extrusion and the reconstituted OBs. Electrostatic deposition of polysaccharides significantly improves the stability of OBs emulsions. OBs emulsions have promising applications to encapsulate bioactive compounds, deliver targeted drugs, and prepare gels and edible functional films. The digestive behavior of OBs emulsions is similar to that of protein-stabilized emulsions, which can increase the satiety, effectively help reduce calorie intake and improve the bioavailability of functional factors. It has also promoted the development of simulated dairy, spices and meat products.

scholarly journals Peroxisome extensions deliver the Arabidopsis SDP1 lipase to oil bodies

2015 ◽  
Vol 112 (13) ◽  
pp. 4158-4163 ◽  
Author(s):  
Nelcy Thazar-Poulot ◽  
Martine Miquel ◽  
Isabelle Fobis-Loisy ◽  
Thierry Gaude
Keyword(s):  
Protein Trafficking ◽  
Protein Transport ◽  
Energy Resource ◽  
High Energy ◽  
Eukaryotic Cells ◽  
Oil Bodies ◽  
Energy Demands ◽  
Lipid Store ◽  
Lipid Stores

Lipid droplets/oil bodies (OBs) are lipid-storage organelles that play a crucial role as an energy resource in a variety of eukaryotic cells. Lipid stores are mobilized in the case of food deprivation or high energy demands—for example, during certain developmental processes in animals and plants. OB degradation is achieved by lipases that hydrolyze triacylglycerols (TAGs) into free fatty acids and glycerol. In the model plant Arabidopsis thaliana, Sugar-Dependent 1 (SDP1) was identified as the major TAG lipase involved in lipid reserve mobilization during seedling establishment. Although the enzymatic activity of SDP1 is associated with the membrane of OBs, its targeting to the OB surface remains uncharacterized. Here we demonstrate that the core retromer, a complex involved in protein trafficking, participates in OB biogenesis, lipid store degradation, and SDP1 localization to OBs. We also report an as-yet-undescribed mechanism for lipase transport in eukaryotic cells, with SDP1 being first localized to the peroxisome membrane at early stages of seedling growth and then possibly moving to the OB surface through peroxisome tubulations. Finally, we show that the timely transfer of SDP1 to the OB membrane requires a functional core retromer. In addition to revealing previously unidentified functions of the retromer complex in plant cells, our work provides unanticipated evidence for the role of peroxisome dynamics in interorganelle communication and protein transport.

scholarly journals HRDGene Dependence of Endoplasmic Reticulum-associated Degradation

2000 ◽  
Vol 11 (5) ◽  
pp. 1697-1708 ◽  
Author(s):  
Sharon Wilhovsky ◽  
Richard Gardner ◽  
Randolph Hampton
Keyword(s):  
Endoplasmic Reticulum ◽  
Membrane Proteins ◽  
Protein Degradation ◽  
Degradation Pathway ◽  
Encoded Proteins ◽  
Absolute Dependence ◽  
Coa Reductase ◽  
Ubiquitin Conjugating Enzymes ◽  
Er Membrane

Work from several laboratories has indicated that many different proteins are subject to endoplasmic reticulum (ER) degradation by a common ER-associated machinery. This machinery includes ER membrane proteins Hrd1p/Der3p and Hrd3p and the ER-associated ubiquitin-conjugating enzymes Ubc7p and Ubc6p. The wide variety of substrates for this degradation pathway has led to the reasonable hypothesis that the HRD (Hmg CoA reductase degradation) gene-encoded proteins are generally involved in ER protein degradation in eukaryotes. We have tested this model by directly comparing the HRD dependency of the ER-associated degradation for various ER membrane proteins. Our data indicated that the role of HRD genes in protein degradation, even in this highly defined subset of proteins, can vary from absolute dependence to complete independence. Thus, ER-associated degradation can occur by mechanisms that do not involve Hrd1p or Hrd3p, despite their apparently broad envelope of substrates. These data favor models in which the HRD gene-encoded proteins function as specificity factors, such as ubiquitin ligases, rather than as factors involved in common aspects of ER degradation.

scholarly journals SGTA-Dependent Regulation of Hsc70 Promotes Cytosol Entry of Simian Virus 40 from the Endoplasmic Reticulum

2017 ◽  
Vol 91 (12) ◽  
Author(s):  
Allison Dupzyk ◽  
Jeffrey M. Williams ◽  
Parikshit Bagchi ◽  
Takamasa Inoue ◽  
Billy Tsai
Keyword(s):  
Endoplasmic Reticulum ◽  
Biological Membrane ◽  
Critical Role ◽  
Simian Virus 40 ◽  
Simian Virus ◽  
Membrane Penetration ◽  
Critical Function ◽  
Nonenveloped Virus ◽  
Er Membrane

ABSTRACT Membrane penetration by nonenveloped viruses remains enigmatic. In the case of the nonenveloped polyomavirus simian virus 40 (SV40), the virus penetrates the endoplasmic reticulum (ER) membrane to reach the cytosol and then traffics to the nucleus to cause infection. We previously demonstrated that the cytosolic Hsc70-SGTA-Hsp105 complex is tethered to the ER membrane, where Hsp105 and SGTA facilitate the extraction of SV40 from the ER and transport of the virus into the cytosol. We now find that Hsc70 also ejects SV40 from the ER into the cytosol in a step regulated by SGTA. Although SGTA's N-terminal domain, which mediates homodimerization and recruits cellular adaptors, is dispensable during ER-to-cytosol transport of SV40, this domain appears to exert an unexpected post-ER membrane translocation function during SV40 entry. Our study thus establishes a critical function of Hsc70 within the Hsc70-SGTA-Hsp105 complex in promoting SV40 ER-to-cytosol membrane penetration and unveils a role of SGTA in controlling this step. IMPORTANCE How a nonenveloped virus transports across a biological membrane to cause infection remains mysterious. One enigmatic step is whether host cytosolic components are co-opted to transport the viral particle into the cytosol. During ER-to-cytosol membrane transport of the nonenveloped polyomavirus SV40, a decisive infection step, a cytosolic complex composed of Hsc70-SGTA-Hsp105 was previously shown to associate with the ER membrane. SGTA and Hsp105 have been shown to extract SV40 from the ER and transport the virus into the cytosol. We demonstrate here a critical role of Hsc70 in SV40 ER-to-cytosol penetration and reveal how SGTA controls Hsc70 to impact this process.

Cooperative and independent activities of Sgt2 and Get5 in the targeting of tail-anchored proteins

2011 ◽  
Vol 392 (7) ◽  
Author(s):  
Christian Kohl ◽  
Peter Tessarz ◽  
Karina von der Malsburg ◽  
Regina Zahn ◽  
Bernd Bukau ◽  
...  
Keyword(s):  
Molecular Chaperones ◽  
Protein Sorting ◽  
Interaction Partner ◽  
Parallel Pathways ◽  
Chaperone Interactions ◽  
Ta Proteins ◽  
Tpr Domain ◽  
Er Membrane

Abstract TPR proteins modulate the activity of molecular chaperones. Here, we describe the S. cerevisiae TPR protein Sgt2 as interaction partner of Ssa1 and Hsp104 and as a component of the GET pathway by interacting with Get5. The GET pathway mediates the sorting of tail-anchored (TA) proteins, harboring a C-terminal trans-membrane segment, to the ER membrane. S. cerevisiae sgt2Δ cells show partial defects in TA protein sorting. Sgt2 activity in vivo relies on its N- and C-terminal domains, whereas the central TPR domain and thus chaperone interactions are dispensable. We show that TA protein sorting defects are more severe in sgt2Δ get5Δ mutants compared to single knockouts. Furthermore, overproduction of Sgt2 becomes toxic to get3Δ but not to get5Δ cells. Together, these findings indicate an additional, Get5-independent role of Sgt2 in TA protein sorting, pointing to parallel pathways of substrate delivery to Get3.

scholarly journals Cellular Localization of Isoprenoid Biosynthetic Enzymes inMarchantia polymorpha. Uncovering a New Role of Oil Bodies

2000 ◽  
Vol 124 (3) ◽  
pp. 971-978 ◽  
Author(s):  
Claude Suire ◽  
Florence Bouvier ◽  
Ralph A. Backhaus ◽  
Dominique Bégu ◽  
Marc Bonneu ◽  
...  
Keyword(s):  
Cellular Localization ◽  
Biosynthetic Enzymes ◽  
Oil Bodies

scholarly journals Role of LARP6 and Nonmuscle Myosin in Partitioning of Collagen mRNAs to the ER Membrane

PLoS ONE ◽  
2014 ◽  
Vol 9 (10) ◽  
pp. e108870 ◽  
Author(s):  
Hao Wang ◽  
Branko Stefanovic
Keyword(s):  
Nonmuscle Myosin ◽  
Er Membrane
Sign in / Sign up

Export Citation Format

Share Document