site (sIt)

A place or location.situs; [L. situs]
acceptor s.the ribosomal binding s. for the aminoacyl-tRNA during protein synthesis.
acceptor splicing s.right splicing junction
active s.that portion of an enzyme molecule at which the actual reaction proceeds; considered to consist of one or more residues or atoms in a spatial arrangement that permits interaction with the substrate to effect the reaction of the latter.
allosteric s.postulated as the place on an enzyme, other than the active s., where a compound, which may be the ultimate product of the biosynthetic pathway involving the enzyme, may bind and influence the activity of the enzyme by changing the enzyme's conformation; the influence of CTP on aspartate carbamoyltransferase activity exemplifies the concept of an allosteric site on an allosteric protein.
antibody combining s.paratope
antigen-binding s.paratope
antigen-combining site See paratope.
cleavage s.restriction s
combining s.paratope
fragile s. [MIM*136540-136670] a non-staining gap at a specific point on a chromosome, usually involving both chromatids, always at the same point on chromosomes of different cells from an individual or kindred; it results in in vitro production of acentric fragments, deleted chromosomes, or other chromosome anomalies; inherited as a dominant chromosome marker.
immunologically privileged s.'ss.'s where allografts are not readily rejected, probably because these particular areas have poor lymphatic drainage.
ligand binding s.the s. on a protein's surface that binds a ligand; equivalent to the active s. if the ligand is the substrate of an enzyme.
privileged anatomic area lacking lymphatic drainage, such as the brain, cornea, and hamster cheek pouch, in which heterologous tumors may grow because the host does not become sensitized.
receptor s.point of attachment of viruses, hormones, or other activators to cell membranes.
replication s.the in vivo s. on DNA of DNA replication.
restriction s.a s. in nucleic acid in which the bordering bases are of such a type as to leave them vulnerable to the cleaving action of an endonuclease.cleavage s;
sequence-tagged s.'s (STSs) short stretches of DNA sequences that can be detected by use of the polymerase chain reaction.
switching s.the break point in a DNA sequence at which a gene segment unites with another gene segment, as in the production of the immunoglobulins.


Browse Medical References:

[A] [B] [C] [D] [E] [F] [G] [H] [I] [J] [K] [L] [M]
[N] [O] [P] [Q] [R] [S] [T] [U] [V] [W] [X] [Y] [Z]