Calelectrin, a Calcium‐Dependent Membrane‐Binding Protein Associated with Secretory Granules in Torpedo Cholinergic Electromotor Nerve Endings and Rat Adrenal Medulla

  title={Calelectrin, a Calcium‐Dependent Membrane‐Binding Protein Associated with Secretory Granules in Torpedo Cholinergic Electromotor Nerve Endings and Rat Adrenal Medulla},
  author={J. H. Walker and Jost Obrocki and Thomas C. S{\"u}dhof},
  journal={Journal of Neurochemistry},
Abstract: Calelectrin, a calcium‐dependent membrane‐binding protein of subunit molecular weight 32,000 has been isolated from the electric organ of Torpedo, and shown to occur in cholinergic neurones and in bovine adrenal medulla. In this study a monospecific antiserum against the Torpedo protein has been used to study the localization of calelectrin in the rat adrenal gland. The cortex was not stained, whereas in the medulla the cytoplasm of the chromaffin cells was stained in a particulate… 

Calmodulin Binding Proteins of the Cholinergic Electromotor Synapse: Synaptosomes, Synaptic Vesicles, Receptor‐Enriched Membranes, and Cytoskeleton

Calmodulin binding proteins (CBPs) have been identified using a gel overlay technique for fractions isolated from Torpedo electromotor nerve endings using data from Triton X‐100‐insoluble cytoskeleton of synaptosomes and calelectrin does not bind calmodulin.

Isolation of mammalian calelectrins: a new class of ubiquitous Ca2+-regulated proteins.

It is suggested that the evolutionary conservation and diversification, the high tissue concentrations, and the Ca2+-specific interactions of the calelectrins make them candidates for Ca2-dependent regulators of membrane events in animal cells.

Control of the Amount of a 34K Ca2+‐Dependent Membrane Binding Protein (Calelectrin)

Results support the idea that 34K is an important structural constituent of mature synapses, an observation suggesting the involvement of this protein in the function of the mature synapse.

Calpactins: two distinct Ca++-regulated phospholipid- and actin-binding proteins isolated from lung and placenta

Three forms of calpactin, the 36,000 Mr Ca++-binding cytoskeletal protein, were isolated in large amounts from bovine lung and human placenta using cycles of calcium-dependent precipitation followed

Characterization of Calelectrin, a Ca2+‐Binding Protein Isolated from the Electric Organ of Torpedo marmorata

It is concluded that calelectrin is a Ca2+‐binding protein whose binding to the lipid moieties of membranes is regulated by physiological changes in theCa2+ concentration.

Calcium-sensitive, lipid-binding cytoskeletal proteins of the human placental microvillar region

A group of Ca2+-sensitive proteins located in the microvillar region of the human placental syncytiotrophoblast are described that associate with both the cytoskeleton and lipid at high concentrations of free Ca2+.

Collagen‐Binding proteins of mammary epithelial cells are related to Ca2+‐and phospholipid‐binding annexins

Three major proteins of 34, 36, and 38 kDa were isolated from mebrane preparations of chemically induced mammary tumors of the rat by collagen type I affinity chromatography and therefore were termed collagen‐binding proteins (CBP), demonstrated to be immunologically related to CBP.



Isolation from Cholinergic Synapses of a Protein That Binds to Membranes in a Calcium‐Dependent Manner

  • J. Walker
  • Biology, Chemistry
    Journal of neurochemistry
  • 1982
A protein that binds to membranes in a calcium‐dependent manner between calcium concentrations of 10−5 and 10−6M has been isolated in large amounts from the entirely cholinergic electric organ of Torpedo marmorata and was localised in the synaptic region of the electric organ by means of immunofluorescence.

Calcium‐Dependent Binding of Cytosolic Proteins by Chromaffin Granules from Adrenal Medulla

Purified chromaffin granules from bovine adrenal medulla bound a small group of medullary cell cytosol proteins at micromolar levels of Ca2+ and physiological levels of K+, Mg2+, and Mg‐ATP, which did not correspond with any previously reported cytosolic components of Chromaffin cells.

Calelectrin self‐aggregates and promotes membrane aggregation in the presence of calcium.

The Ca2+‐induced self‐association of calelectrin and its aggregation enhancing effect may be of great importance to the structural organization of neural and secretory cells and the mechanism of exocytosis.


Abstract— Fluorescein isothiocyanate‐labelled lectins were used to identify lectin‐binding glycoproteins of the chromaffin granule after electrophoresis of the membrane and soluble granule proteins

Chemical composition of cholinergic synaptic vesicles from Torpedo marmorata based on improved purification.

Cholinergic synaptic vesicles from the electric organ of Torpedo marmorata have been purified to a constant composition and a higher transmitter content than previously reported, and characterisation by two-dimensional gel electrophoresis suggested that it is an actin-like polypeptide.

Mechanochemical properties of brain clathrin: interactions with actin and alpha-actinin and polymerization into basketlike structures or filaments.

Because of clathrin's biochemical and biophysical properties, its interaction with contractile proteins, and its presence in the membrane of vesicles of various cell types, it is classified in the group of mechanochemical proteins.

Clathrin: a unique protein associated with intracellular transfer of membrane by coated vesicles.

  • B. Pearse
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 1976
The amount of clathrin in lymphoma cells suggests that coated vesicles transfer substantial amounts of membrane within cells, not necessarily in association with a secretory process.