在2009年9月21日的Journal of Cell Biology的一篇报道中，Nowak等人介绍了上皮细胞脂膜中维持细胞形状的蛋白质网络，以及在老鼠晶状体中该网络维持细胞形状和有序排列的机制。
蛋白网络中的血影蛋白（Spectrin），F肌动蛋白（F-actin）以及其他的相关蛋白能够支撑和定形红细胞的脂膜。在其他类型的细胞中同样存在着相似的网络，包括晶体上皮细胞。脂膜骨架中的肌丝（Actin filament），是通过网络中的相关蛋白固定的，如肌动蛋白结合蛋白（actin-binding protein）的原肌球蛋白家族和原肌球调节蛋白家族的成员。
在缺少肌球调节蛋白1的老鼠中，其晶体上皮细胞质膜骨架中的gamma原肌球蛋白同样也会缺失。F肌动蛋白和血影蛋白虽然仍在细胞的脂膜中，以往连续的网络中却出现了裂口，表明这两个肌动蛋白结合蛋白稳固了肌丝，而肌丝对网络来数是必需的。电子显微扫描显示，缺少肌球调节蛋白1的细胞出现形状扭曲以及不规则的排列。
Velia Fowler解释说，血影肌动蛋白网络的破坏改变了相邻细胞间的相互粘合，导致细胞形状改变和晶状体相关的机械应力混乱。（生物谷Bioon.com）
生物谷推荐原始出处：
The Journal of Cell Biology, Vol. 186, No. 6, 915-928 doi:10.1083/jcb.200905065
Tropomodulin1 is required for membrane skeleton organization and hexagonal geometry of fiber cells in the mouse lens
Roberta B. Nowak1, Robert S. Fischer1, Rebecca K. Zoltoski2, Jerome R. Kuszak3, and Velia M. Fowler1
1 Department of Cell Biology, The Scripps Research Institute, La Jolla, CA 92037
2 Department of Biological Health Sciences, Illinois College of Optometry, Chicago, IL 60616
3 Departments of Pathology and Ophthalmology, Rush University Medical Center, Chicago, IL 60612
Hexagonal packing geometry is a hallmark of close-packed epithelial cells in metazoans. Here, we used fiber cells of the vertebrate eye lens as a model system to determine how the membrane skeleton controls hexagonal packing of post-mitotic cells. The membrane skeleton consists of spectrin tetramers linked to actin filaments (F-actin), which are capped by tropomodulin1 (Tmod1) and stabilized by tropomyosin (TM). In mouse lenses lacking Tmod1, initial fiber cell morphogenesis is normal, but fiber cell hexagonal shapes and packing geometry are not maintained as fiber cells mature. Absence of Tmod1 leads to decreased TM levels, loss of F-actin from membranes, and disrupted distribution of β2-spectrin along fiber cell membranes. Regular interlocking membrane protrusions on fiber cells are replaced by irregularly spaced and misshapen protrusions. We conclude that Tmod1 and TM regulation of F-actin stability on fiber cell membranes is critical for the long-range connectivity of the spectrin–actin network, which functions to maintain regular fiber cell hexagonal morphology and packing geometry.
