Red Cell Membrane

Delaunay, Jean

doi:10.1007/978-1-4757-9537-0_1

Cited by 9 publications

(9 citation statements)

References 179 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…⌺6 localized to AIS in the cerebral cortex and hippocampus (Fig. 3, B and D), as well as in other regions, 3 of ⌺1 Ϫ/Ϫ brain. As expected from the much higher expression level of ⌺6 than ⌺1 in the brain (Ref.…”

Section: Generation Of ⌺1mentioning

confidence: 84%

“…Heterozygous offspring did not display an overt phenotype. 3 Heterozygous mutant mice were intercrossed to derive ⌺1 Ϫ/Ϫ mice. Genotyping of the offspring by PCR using tail DNAs as templates (Fig.…”

Section: Generation Of ⌺1mentioning

confidence: 99%

“…1E) showed that the homozygous mice were recovered according to Mendelian expectations. 3 To examine the expression of ⌺1 and ⌺6 in the homozygous mutants, brain lysates from wild-type and ⌺1 Ϫ/Ϫ mice, as well as from a ⌺1⌺6 Ϫ/Ϫ mouse (11), were immunoblotted with anti-␤IV-spectrin antibody. This antibody recognizes the variable region of ␤IV-spectrin, which is present in both ⌺1 and ⌺6 (Fig.…”

Section: Generation Of ⌺1mentioning

confidence: 99%

“…This is most likely due to a neurological defect that affects sexual behavior, because the histology of their reproductive tissues (testis and epididymis) as well as the morphology and movement of isolated sperms appeared normal, and the mutant mice showed no sign of copulation with wild-type females as judged by the presence of vaginal plugs. 3 When four ⌺1 Ϫ/Ϫ male mice were crossed with wild-type females, by contrast, they all exhibited normal fertility. Overall, the gross phenotypes observed in ⌺1⌺6 Ϫ/Ϫ mice were rescued or milder in ⌺1 Ϫ/Ϫ mice, indicating that ⌺6 is essential for normal neuronal functions.…”

Section: Generation Of ⌺1mentioning

confidence: 99%

“…One is to physically stabilize the plasma membrane integrity. In hereditary diseases with mutations in the erythrocyte-specific ␣I-and ␤I-spectrin genes, the erythrocyte membrane becomes fragile, resulting in elliptocytosis and spherocytosis, and eventually hemolytic anemia (3). The second role is to cluster specific integral membrane proteins at high density in specialized regions of the plasma membrane.…”

mentioning

confidence: 99%

See 4 more Smart Citations

Specific Role of the Truncated βIV-Spectrin Σ6 in Sodium Channel Clustering at Axon Initial Segments and Nodes of Ranvier

Uemoto

Suzuki

Terada

et al. 2007

Journal of Biological Chemistry

View full text Add to dashboard Cite

At axon initial segments and nodes of Ranvier in neurons, the spectrin membrane skeleton plays roles in physically stabilizing the plasma membrane integrity and in clustering voltage-gated sodium channels for proper conduction of the action potential. ␤IV-Spectrin, an essential component of the membrane skeleton at these sites, has an N-terminal-truncated isoform, ⌺6, which is expressed at much higher levels than the full-length isoform ⌺1. To investigate the role of ␤IV-spectrin ⌺6, we generated ⌺1-deficient mice with a normal level of ⌺6 expression (⌺1 ؊/؊ mice), and compared their phenotypes with those of previously generated mice lacking both ⌺1 and ⌺6 (⌺1⌺6 ؊/؊ mice). The gross neurological defects observed in ⌺1⌺6 ؊/؊ mice, such as hindleg contraction, were apparently ameliorated in ⌺1 ؊/؊ mice. At cellular levels, ⌺1⌺6 ؊/؊ and ⌺1 ؊/؊ neurons similarly exhibited waving and swelling of the plasma membrane at axon initial segments and nodes of Ranvier. By contrast, the levels of ankyrin G and voltage-gated sodium channels at these sites, which are significantly reduced in ⌺1⌺6 ؊/؊ mice, were substantially recovered in ⌺1 ؊/؊ mice. We conclude that the truncated ␤IV-spectrin isoform ⌺6 plays a specific role in clustering voltage-gated sodium channels, whereas it is dispensable for membrane stabilization at axon initial segments and nodes of Ranvier.The spectrin membrane skeleton is a polygonal cytoskeletal meshwork attached to the cytoplasmic face of the plasma membrane (1). The basic unit of the spectrin skeleton is a heterotetramer of two ␣-spectrin and two ␤-spectrin proteins. ␤-Spectrin has an N-terminal actin-binding domain, and the spectrin tetramers are bound to one another indirectly via short actin filaments to form the meshwork. ␤-Spectrin also binds to a membrane adaptor protein ankyrin via the spectrin repeat 15 (2), thereby allowing the attachment of the spectrin-actin meshwork to the plasma membrane. Two major roles are known for the spectrin skeleton. One is to physically stabilize the plasma membrane integrity. In hereditary diseases with mutations in the erythrocyte-specific ␣I-and ␤I-spectrin genes, the erythrocyte membrane becomes fragile, resulting in elliptocytosis and spherocytosis, and eventually hemolytic anemia (3). The second role is to cluster specific integral membrane proteins at high density in specialized regions of the plasma membrane. For example, ␣II-and ␤II-spectrins stabilize the clustering of Na ϩ /K ϩ -ATPase at cell-cell contact sites in polarized epithelial cells through ankyrin B-mediated interaction with Na ϩ /K ϩ

show abstract

Section: Generation Of ⌺1mentioning

confidence: 84%

Section: Generation Of ⌺1mentioning

confidence: 99%

Section: Generation Of ⌺1mentioning

confidence: 99%

Section: Generation Of ⌺1mentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations