Glossary for NanoBiotechnology
A-kinase (cyclic AMP-dependent protein
Enzyme that phosphorylates target proteins in response to a rise
in intracellular cyclic AMP. First identified in skeletal muscle
as part of the pathway of regulation of glycogen breakdown in
response to adrenaline.
Members of a large superfamily of membrane transport proteins
that hydrolyze ATP and transfer a diverse array of small molecules
across a membrane.
Chemical group derived from acetic acid. Acetyl groups are
important in metabolism and often added as a covalent modification
Small water-soluble molecule that carries acetyl groups in cells.
Comprises an acetyl group linked to coenzyme A (CoA) by an easily
hydrolyzable thioester bond.
Neurotransmitter that functions at cholinergic chemical synapses,
found both in the brain and in the peripheral nervous system. It
is the neurotransmitter at vertebrate neuromuscular junctions.
Ion channel that opens in response to acetylcholine binding,
thereby converting a chemical signal into an electrical one.
Best understood example of a ligand-gated channel. Sometimes
called the nicotinic acetylcholine receptor to distinguish
it from a muscarinic receptor, which is a G-protein-linked
Long, thin, actin-containing spike produced from the head of certain
sperm when they make contact with the egg. Seen in sea urchins and
other marine invertebrates whose eggs are surrounded by a thick
Region at the head end of a sperm cell that contains a sac of hydrolytic
enzymes used to digest the protective coating of the egg.
Abundant protein that forms actin filaments in all eucaryotic cells.
The monomeric form is sometimes called globular or G-actin; the
polymeric form is filamentous or F-actin.
Protein that associates with either actin monomers or actin
filaments in cells and modifies their properties. Examples
include myosin, a-actinin, and
actin filament (microfilament):
Helical protein filament formed by the polymerization of globular
actin molecules. A major constituent of the cytoskeleton of all
eucaryotic cells and part of the con- tractile apparatus of skeletal
Rapid, transient, self-propagating electrical excitation in the
plasma membrane of a cell such as a neuron or muscle cell. Action
potentials, or nerve impulses, allow long-distance signaling in
the nerveous system.
Extra energy that must be possessed by atoms or molecules in addition
to their ground-state energy in order to undergo a particular chemical
Region of an enzyme surface to which a substrate molecule binds
in order to undergo a catalyzed reaction.
Movement of a molecule across a membrane or other barrier driven
by energy other than that stored in the concentration gradient or
electrochemical gradient of the transported molecule.
Functional group derived from a carboxylic acid. (R represents
an alkyl group, such as methyl.)
Parts of the glossary are from the following book:
Copyright 1983, 1989, 1994 From "Molecular Biology of the Cell" by
Bruce Alberts, Dennis Bray, Julian Lewis, Martin Raff, Keith Roberts,
James D. Watson. Reproduced by permission of Routledge, Inc., part of
The Taylor & Francis Group.