tubER 7: cecER 9.2: pmaER 7.4
||Budding yeast Saccharomyces cerevisiae
||West M, Zurek N, Hoenger A, Voeltz GK. A 3D analysis of yeast ER structure reveals how ER domains are organized by membrane curvature. J Cell Biol. 2011 Apr 18 193(2):333-46. doi: 10.1083/jcb.201011039 p.335 figure 1H & p.336 left column 2nd paragraphPubMed ID21502358
||Abstract: "[Investigators] analyzed the structure of yeast endoplasmic reticulum (ER) during six sequential stages of budding by electron tomography to reveal a three-dimensional portrait of ER organization during inheritance at a nanometer resolution."
||P.336 left column 2nd paragraph: "[Investigators] used [their] 3D models to calculate the lumenal volume to surface area (V/SA) ratios of all three ER domains. [They] measured the volume to surface area ratios for several regions in [their] models that were unambiguously tubER, cecER, and pmaER (Fig. 1 H, mean V/SA[tubER] = 7.0, V/SA[cecER] = 9.2, and V/SA[pmaER] = 7.4). [They] also calculated for comparison the volume to surface area ratios of 30- and 60-nm vesicles present in [their] samples (V/SA = 5.0 and 10.0, respectively). These data reveal that ER domain shape affects the lumenal volume to membrane surface area ratios. In yeast, the cecER has a larger volume to surface area ratio than tubER and pmaER, which suggests that tubER could be better suited for functions that require a lot of membrane surface area, whereas cecER may be adapted for lumenal processes."