Cytokine, produced from platelet basic protein, that acts as a growth factor.
connexins Generic term for proteins isolated from gap junctions. Currently 21 human genes and 20 mouse genes for connexins have been identified, each with tissue- or cell-type-specific expression. Most organs and many cell types express more than one connexin. Connexin phospho-rylation has been implicated in connexin assembly, gap junction turnover and responses to tumour promoters and oncogenes. Connexin43 (Cx43), the most widely expressed and abundant gap junction protein, can be phosphorylated at several different serine and tyrosine residues. Mutations in connexin genes are associated with peripheral neuropathies, cardiovascular diseases, dermatological diseases, hereditary deafness and cataract. See connexon.
connexon The functional unit of gap junctions. An assembly of six membrane-spanning proteins (connexins) having a water-filled gap in the centre. Two connexons in juxtaposed membranes link to form a continuous pore through both membranes.
conotoxins Toxins from cone shells (Conus spp.). The a-conotoxins (small peptides, 13-18 residues) are competitive inhibitors of nicotinic acetylcholine receptors. The |-conotoxins are small (22-residue) peptides that bind voltage-sensitive sodium channels in muscle, causing paralysis. The w-conotoxins are similar in size and inhibit voltage-gated calcium channels, thereby blocking synaptic transmission.
consensus sequence Of a series of related DNA, RNA or protein sequences, the sequence that reflects the most common choice of base or amino acid at each position. Areas of particularly good agreement often represent conserved functional domains. The generation of consensus sequences has been subject to intensive mathematical analysis.
conservative substitution In a gene product, a substitution of one amino acid with another with generally similar properties (size, hydrophobicity, etc.), such that the overall functioning is likely not to be seriously affected.
CONSTANS CO Arabidopsis gene that promotes flowering in long days. Flowering is induced when CO messenger RNA expression coincides with the exposure of plants to light. A member of a family of 17 CO-like genes that are widely distributed in plants. Product is a nuclear zinc-finger protein.
constant region The C-terminal half of the light or the heavy chain of an immunoglobulin molecule. The amino acid sequence in this region is the same in all molecules of the same class or subclass whereas the variable region is antigen-specific.
constitutive Constantly present, whether there is demand or not. Thus some enzymes are constitutively produced, whereas others are inducible.
Was this article helpful?
If you have heard about metabolism, chances are it is in relation to weight loss. Metabolism is bigger than weight loss, though, as you will learn later on. It is about a healthier, better you. If you want to fire up your metabolism and do not have any idea how to do it, you have come to the right place. If you have tried to speed up your metabolism before but do not see visible results, you have also come to the right place.