SEED LIPID DROPLET PROTEIN1, SEED LIPID DROPLET PROTEIN2, and LIPID DROPLET PLASMA MEMBRANE ADAPTOR mediate lipid droplet–plasma membrane tethering

• DOI: 10.1093/plcell/koac095
• Publication Date: 2022-03-26T04:13:40Z
• Authors: Hannah Elisa Kraw...; Siqi Sun; Nathan M Doner; Qiqi Yan; Magdiel Sheng Sat...; Patricia Scholz; Philipp William N...; Kerstin Schmitt; Oliver Valerius; Roman Pleskot; Stefan Hillmer; Gerhard H Braus; Marcel Wiermer; Robert T Mullen; Till Ischebeck
• Keywords: Organelle; Tethering; Lipid droplet; Membrane contact site

Membrane contact sites (MCSs) are interorganellar connections that allow for the direct exchange of molecules, such as lipids or Ca2+ between organelles, but can also serve to tether organelles at specific locations within cells. Here, we identified and characterized three proteins Arabidopsis thaliana form a lipid droplet (LD)-plasma membrane (PM) tethering complex in plant cells, namely LD-localized SEED LD PROTEIN (SLDP) 1 SLDP2 PM-localized LD-PLASMA MEMBRANE ADAPTOR (LIPA). Using proteomics different protein-protein interaction assays, show both SLDPs associate with LIPA. Disruption either SLDP1 expression, LIPA, leads an aberrant clustering LDs seedlings. Ectopic co-expression one LIPA is sufficient reconstitute LD-PM Nicotiana tabacum pollen tubes, cell type by dynamically moving cytosolic streaming. Furthermore, confocal laser scanning microscopy revealed SLDP2.1 be enriched These other results suggest SLDP interact anchors subset PM during post-germinative seedling growth Arabidopsis.