The dynamic nature of the Golgi complex.

TLDR

At 20 °C, vesicular stomatitis virus G protein transport is blocked, leading to accumulation in the trans‑Golgi network, which previous studies reported to enlarge under this condition. The study aims to quantify the volume and surface area of the Golgi stack and TGN in baby hamster kidney cells under different temperatures and infection states. Stereological techniques were used to measure these parameters in cells at 20 °C and 37 °C, with and without Semliki Forest virus infection. The results reveal that at 20 °C the TGN enlarges while preceding Golgi compartments shrink in surface area and volume—a pattern also observed in uninfected cells at 20 °C and during normal infection at 37 °C—yet transport to the cell surface remains unaffected, demonstrating that the Golgi stack and TGN are dynamic, interrelated structures that rapidly alter total surface area in response to membrane transport rates.

Abstract

The intracellular transport of newly synthesized G protein of vesicular stomatitis virus is blocked at 20 degrees C and this spanning membrane glycoprotein accumulates in the last Golgi compartment, the trans Golgi-network (TGN). Previous morphological evidence suggested that the TGN enlarged significantly under this condition. In the present study we have used stereological procedures to estimate the volume and surface area of the Golgi stack and the TGN of baby hamster kidney cells under different conditions. The results indicate that the increase in the size of the TGN at 20 degrees C is accompanied by a significant decrease in the surface area and volume of the preceding Golgi compartments. A similar effect is also seen in uninfected cells at 20 degrees C, as well as during normal (37 degrees C) infection with Semliki Forest virus. In the latter case, however, the decrease in the size of the Golgi stack and the increase in that of the TGN is not accompanied by inhibition of transport from the Golgi complex to the cell surface. The results indicate that the Golgi stack and the TGN are dynamic and interrelated structures that are capable of rapid alteration in total surface area in response to changes in the rates of membrane transport.