Biology Reference
In-Depth Information
FIGURE 18.1
Flow of genetic information, biological interactions and main molecular networks in the eukaryotic cell. (A) Flow of genetic
information (central dogma of molecular biology) from DNA to RNA to proteins
[56
e
58]
(solid arrows), and whole spectrum of biological interactions/
networks at all different levels (from supramolecular to molecular level) in the eukaryotic cell: DNA
e
DNA; DNA
e
RNA; DNA
e
protein;
DNA
e
metabolites; RNA
e
RNA; RNA
e
protein (RNP); RNA
e
metabolites; protein
e
protein; protein
e
metabolites and metabolite
e
metabolite interac-
tions. Adapted from
[59]
with permission from Faculty of 1000 Ltd (F1000 Ltd;
http://f1000.com
). (B) Standard schematic representation of main bio-
logical entities and networks participating in the flow of genetic information (solid arrows), including whole spectrum of essential interactions/networks
between them (dashed arrows), responsible for a specific phenotype in interaction with the environment. Reproduced from
[60]
with permission from
Springer.
integration, using well-curated and up-to-date databases and
data repositories, is of central importance
[16,61]
.
S. cerevisiae is a species of budding yeast, a group of
unicellular fungi belonging to the phylum Ascomycota. This
yeast is being used as a model eukaryote because its basic
mechanisms of DNA and chromosome replication, cell
division, gene expression, translation, signal transduction and
regulatory networks, metabolism and subcellular organiza-
tion are essentially conserved between yeast and higher
eukaryotes
[61
it has GenerallyRegarded as Safe (GRAS) status and is a free-
living organism with rapid growth, and simple methods of
cultivation under defined conditions. It also has awell-defined
genetic system with simple techniques of genetic manipula-
tion. The yeast S. cerevisiaewas the first eukaryotic organism
for which the complete genome was sequenced
[69]
,for
which strategies for the proper annotation, curation and
standards initiatives for maintenance of high quality curated
databases and data repositories were implemented (e.g.,
Saccharomyces genome database;
http://www.yeastgenome.
genomic technologies (including NGS/RNA sequencing and
the latest proteomics andmetabolomics techniques) were first
developed and validated in yeast (see
[16,17]
and references
therein). The yeast S. cerevisiae is being used as a model
organism to study cell growth; the cell cycle; checkpoints and
64]
. The essentials of eukaryotic biochem-
istry, as encompassed in a complete map of central metabolic
pathways were first unveiled in S. cerevisiae
[56,62,65,66]
,
and a wide knowledge of the genetics, biochemistry, func-
tional genomics and physiology of this yeast is now available
[61
e
64,67,68]
. Among the properties that make S. cerevisiae
a particularly suitable organism for biological studies are that
e
