Isolation of the Plant Exocyst Complex

Abstract

The exocyst, conserved from yeast to plants to mammals, is a hetero-octameric complex that mediates tethering of secretory vesicles to designated sites on the plasma membrane during polarized exocytosis. Because structural studies of the intact exocyst complex have been greatly limited by the low yields of purified proteins, many aspects of the exocyst functions remain poorly understood. Here, we present the protocols for the isolation and purification of the recombinant and the native plant exocyst complex. Given the known diversification of the exocyst subunits in plants, our protocols will likely open the possibility of unraveling the functional significance of these subunits in the context of the fully assembled exocyst complex.

Exocyst controls exosome biogenesis via Rab11a

“…41 MVBs can fuse with autophagosomes or directly with lysosomes after autophagy activation. 42 Fader et al proposed that autophagy increases the fusion of MVBs with autophagosomes, which directly increases the degradation of MVBs and eventually reduces exosome release. 43 Recent studies have suggested that cellular ho-meostasis decides the degradation or secretion of exosomes.…”

“…These results provided additional evidence supporting the formation of the exocyst in cells, with Sec3 and Exo70 located at the plasma membrane to promote the attachment of the exocyst to the membrane and with Sec10 acting as part of the central hub of the exocyst. 41,42 Sec10 knockdown inhibited the delivery of vesicles to the membrane, causing Sec3 and Exo70 on the membrane to have fewer vesicles to bind to. In contrast, Sec3 or Exo70 knockdown did not affect the formation of the exocyst, except with vesicles tethered to the plasma membrane.…”