title: Barriers to uniformity within the endoplasmic reticulum.
abstract: Differentiating the endoplasmic reticulum (ER) into different physical domains may help the ER spatially regulate its many functions. For example, ER sheets are highly decorated with ribosomes for protein synthesis, whereas tubules usually correspond to smooth ER. Hence, ER morphology may play direct roles in functional diversification within the ER. The ER also makes direct physical contacts with other organelles, called ER junctions, enabling further functional diversification through input from external sources. In yeast, an ER diffusion barrier has now been discovered at the bud neck that compartmentalizes the ER into bud and mother diffusion domains by restricting the lateral diffusion of ER membrane proteins. Therefore, diffusion barriers also likely contribute to functional diversification within the ER by creating suites of molecular factors within ER diffusion domains.
authors.affiliation: Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver V6T 1Z3, Canada.
authors.forename: Andrew K  O
authors.initials: AK
authors.lastname: Wong
authors.affiliation: Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver V6T 1Z3, Canada.
authors.forename: Jesse T
authors.initials: JT
authors.lastname: Chao
authors.affiliation: Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver V6T 1Z3, Canada. Electronic address: cloewen@mail.ubc.ca.
authors.forename: Christopher J R
authors.initials: CJ
authors.lastname: Loewen
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D004058:Diffusion; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism; D058112:Septins / Q000378:metabolism
chemical_list: D058112:Septins