Similar to the workings of a postal hub, the Golgi apparatus—a large organelle present in all eukaryotic cells—processes, sorts and packages proteins and lipids for transport inside and outside of the cell.
To better understand the Golgi’s complex network of laterally linked stacks, a team of researchers from NTU’s School of Biological Sciences, led by Asst Prof Lu Lei, used super-resolution microscopy to show that the two principal functions of the Golgi—processing and transport—take place in spatially distinct areas of the stacks. Enzymes responsible for processing were predominantly found in the interior, while transport machinery components and cargos with bulky sizes were confined to the cisternal rims.
In a separate study, Asst Prof Lu’s team and his collaborators discovered that amino acids can promote protein trafficking from the endosome—another cellular compartment engaged in molecular sorting—to the Golgi, thereby regulating the cellular localisation of proteins, including receptors that play important roles in cells. By identifying the components of a signalling cascade triggered by amino acid sensing, the findings provide important insights into the effects of nutrients on human physiology and pathology at the molecular and cellular levels.