Biology Reference
In-Depth Information
RNA is then itself translated into a linear chain of amino acids
(translation). This chain in turn folds to form a three-dimensional
structure. Finally, in general under the action of enzymes, this three-
dimensional structure undergoes what are called post-translational
or epigenetic modifications corresponding to chemical modifications
of the amino acids of the protein. According to current theory, the
properties of a protein depend on its three-dimensional structure
which, through its form and electrical charges, permits interactions
with other molecules (see
Molecular interaction
).
Proteome:
All the proteins (and their interactions) of a cell.
Real
: See
Ontology
.
Regulator protein
: Protein in the chromatin which activates or
inhibits gene transcription (see
Chromatin
,
Molecular interaction
).
Regulatory region
: See
Regulatory sequence
,
Promoter
.
Regulatory sequence
: DNA sequence situated upstream of the
genes where the regulatory factors which activate or inhibit gene
transcription bind (see
Protein synthesis
).
Specificity
: That which exclusively identifies a series of things or
organisms which thus constitute a species. However, the word
'specificity' is one of the most used terms in biological literature,
employed with a variety of meanings which are not always
explained. When we speak of molecular specificity, we are using
the term in the original meaning of 'stereospecificity' defined by
molecular biologists. Stereospecificity (etymology: solid speci-
ficity) indicates that molecules are only capable of performing
unequivocal interactions, or very few in number, determined
by their three-dimensional structure. Each molecule has only a
single partner molecule (or a very restricted number of them)
with which it can interact, which excludes random interactions
between molecules.
