2026-04-17T19:06:51Zhttps://recercat.cat/oai/request
oai:recercat.cat:2445/1806882025-12-04T21:14:22Zcom_2072_1057col_2072_478781col_2072_478917
RECERCAT author Grados Torrez, Ricardo Enrique author López-Iglesias, Carmen author Ferrer Artigas, Joan Carles author Campos Martínez, Narciso 2021-10-19T14:08:44Z2021-10-19T14:08:44Z2021-08-242021-10-19T14:08:44Z The membrane domain of eukaryotic HMG-CoA reductase (HMGR) has the conserved capacity to induce endoplasmic reticulum (ER) proliferation and membrane association into Organized Smooth Endoplasmic Reticulum (OSER) structures. These formations develop in response to overexpression of particular proteins, but also occur naturally in cells of the three eukaryotic kingdoms. Here, we characterize OSER structures induced by the membrane domain of Arabidopsis HMGR (1S domain). Immunochemical confocal and electron microscopy studies demonstrate that the 1S:GFP chimera co-localizes with high levels of endogenous HMGR in several ER compartments, such as the ER network, the nuclear envelope, the outer and internal membranes of HMGR vesicles and the OSER structures, which we name ER-HMGR domains. After highpressure freezing, ER-HMGR domains show typical crystalloid, whorled and lamellar ultrastructural patterns, but with wide heterogeneous luminal spaces, indicating that the native OSER is looser and more flexible than previously reported. The formation of ER-HMGR domains is reversible. OSER structures grow by incorporation of ER membranes on their periphery and progressive compaction to the inside. The ER-HMGR domains are highly dynamic in their formation versus their disassembly, their variable spherical-ovoid shape, their fluctuating borders and their rapid intracellular movement, indicating that they are not mere ER membrane aggregates, but active components of the eukaryotic cell. cc-by (c) Grados Torrez, Ricardo Enrique et al., 2021 https://creativecommons.org/licenses/by/4.0/ info:eu-repo/semantics/openAccess Reticle endoplasmàtic Refrigeració Àcid mevalònic Endoplasmic reticulum Cooling Mevalonic acid Loose Morphology and High Dynamism of OSER Structures Induced by the Membrane Domain of HMG-CoA Reductase info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion