Biomaterial Database

Role of myosin in terminal web contraction in isolated intestinal epithelial brush borders. 1985

T C Keller, and K A Conzelman, and R Chasan, and M S Mooseker

We have investigated the role of myosin in contraction of the terminal web in brush borders isolated from intestinal epithelium. At 37 degrees C under conditions that stimulate terminal web contraction (1 microM Ca++ and ATP), most (60-70%) of the myosin is released from the brush border. Approximately 80% of the myosin is also released by ATP at 0 degree C, in the absence of contraction. Preextraction of this 80% of the myosin from brush borders with ATP has no effect on either the time course or extent of subsequently stimulated contraction. However, contraction is inhibited by removal of all of the myosin with 0.6 M KCl and ATP. Contraction is also inhibited by an antibody to brush border myosin, which inhibits both the ATPase activity of brush border myosin and its ability to form stable bipolar polymers. These results indicate that although functional myosin is absolutely required for terminal web contraction only approximately 20% of the brush border myosin is actually necessary. This raises the possibility that there are at least two different subsets of myosin in the terminal web.

UI	MeSH Term	Description	Entries
D007413	Intestinal Mucosa	Lining of the INTESTINES, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. In the SMALL INTESTINE, the mucosa is characterized by a series of folds and abundance of absorptive cells (ENTEROCYTES) with MICROVILLI.	Intestinal Epithelium,Intestinal Glands,Epithelium, Intestinal,Gland, Intestinal,Glands, Intestinal,Intestinal Gland,Mucosa, Intestinal
D008871	Microvilli	Minute projections of cell membranes which greatly increase the surface area of the cell.	Brush Border,Striated Border,Border, Brush,Border, Striated,Borders, Brush,Borders, Striated,Brush Borders,Microvillus,Striated Borders
D009218	Myosins	A diverse superfamily of proteins that function as translocating proteins. They share the common characteristics of being able to bind ACTINS and hydrolyze MgATP. Myosins generally consist of heavy chains which are involved in locomotion, and light chains which are involved in regulation. Within the structure of myosin heavy chain are three domains: the head, the neck and the tail. The head region of the heavy chain contains the actin binding domain and MgATPase domain which provides energy for locomotion. The neck region is involved in binding the light-chains. The tail region provides the anchoring point that maintains the position of the heavy chain. The superfamily of myosins is organized into structural classes based upon the type and arrangement of the subunits they contain.	Myosin ATPase,ATPase, Actin-Activated,ATPase, Actomyosin,ATPase, Myosin,Actin-Activated ATPase,Actomyosin ATPase,Actomyosin Adenosinetriphosphatase,Adenosine Triphosphatase, Myosin,Adenosinetriphosphatase, Actomyosin,Adenosinetriphosphatase, Myosin,Myosin,Myosin Adenosinetriphosphatase,ATPase, Actin Activated,Actin Activated ATPase,Myosin Adenosine Triphosphatase
D010766	Phosphorylation	The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.	Phosphorylations
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D002645	Chickens	Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.	Gallus gallus,Gallus domesticus,Gallus gallus domesticus,Chicken
D000255	Adenosine Triphosphate	An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.	ATP,Adenosine Triphosphate, Calcium Salt,Adenosine Triphosphate, Chromium Salt,Adenosine Triphosphate, Magnesium Salt,Adenosine Triphosphate, Manganese Salt,Adenylpyrophosphate,CaATP,CrATP,Manganese Adenosine Triphosphate,MgATP,MnATP,ATP-MgCl2,Adenosine Triphosphate, Chromium Ammonium Salt,Adenosine Triphosphate, Magnesium Chloride,Atriphos,Chromium Adenosine Triphosphate,Cr(H2O)4 ATP,Magnesium Adenosine Triphosphate,Striadyne,ATP MgCl2
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012995	Solubility	The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Solubilities