biostudies-literatureKrawczyk HENatural Sciences and Engineering Research Council of CanadaGerman research foundation (DFG;BES-Physical Biosciences programUS Department of Energy, Office of Science2172PRoTECT to Till Ischebeck and Marcel WiermerIRTG2424-2448https://www.ebi.ac.uk/biostudies/studies/S-EPMC9134073biostudies-literatureUnknown34(6)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 of Arabidopsis thaliana that form a lipid droplet (LD)-plasma membrane (PM) tethering complex in plant cells, namely LD-localized SEED LD PROTEIN (SLDP) 1 and SLDP2 and PM-localized LD-PLASMA MEMBRANE ADAPTOR (LIPA). Using proteomics and different protein-protein interaction assays, we show that both SLDPs associate with LIPA. Disruption of either SLDP1 and SLDP2 expression, or that of LIPA, leads to an aberrant clustering of LDs in Arabidopsis seedlings. Ectopic co-expression of one of the SLDPs with LIPA is suThe Plant cellSEED LIPID DROPLET PROTEIN1, SEED LIPID DROPLET PROTEIN2, and LIPID DROPLET PLASMA MEMBRANE ADAPTOR mediate lipid droplet-plasma membrane tethering.PMC9134073273/2-2IS 273/10-1RGPIN-2018-04629INST 186/1277-1 FUGG273/7-1DE-SC0016536BR1502-15-1INST 186/1230-1Ischebeck TNiemeyer PWWiermer MYan QScholz PLim MSSBraus GHDoner NMPleskot RSchmitt KKrawczyk HESun SHillmer SMullen RTValerius OfalseSEED LIPID DROPLET PROTEIN1, SEED LIPID DROPLET PROTEIN2, and LIPID DROPLET PLASMA MEMBRANE ADAPTOR mediate lipid droplet-plasma membrane tethering.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 of Arabidopsis thaliana that form a lipid droplet (LD)-plasma membrane (PM) tethering complex in plant cells, namely LD-localized SEED LD PROTEIN (SLDP) 1 and SLDP2 and PM-localized LD-PLASMA MEMBRANE ADAPTOR (LIPA). Using proteomics and different protein-protein interaction assays, we show that both SLDPs associate with LIPA. Disruption of either SLDP1 and SLDP2 expression, or that of LIPA, leads to an aberrant clustering of LDs in Arabidopsis seedlings. Ectopic co-expression of one of the SLDPs with LIPA is su2022-01-01T00:00:00Z2022 May2026-05-07T03:17:32.827Z2025-02-19T02:58:37.101ZS-EPMC91340733534875110.1093/plcell/koac095