Yeast Prions: Their Assembly into Protein Fibrils and the Role of Assembly Modulators - The Functional Fold: Amyloid Structures in Nature - page 94

Figure 6.1 Primary structures of Sup35pNM, Ure2p1-93, Rnq1p153-405,

and Het-S1-289. Q and N residues are coloured red, S and T are
coloured blue. Residues constituting the domains required for
prion propagation are in bold. The structure of the compactly
folded N-terminal domains of Sup35p from S. pombe and that

of Ure2p from are shown. The three sub-domains

of Sup35p C-terminal domains are coloured blue, red, and
green, and the peptide that links this domain to the M domain
of the protein is coloured purple. The two sub-domains of
Ure2p C-terminal domain are coloured blue and green. The
letters N and C in the structure panels refer to the N- and
C-terminal residues of the polypeptide represented. The GTP
molecule bound to Sup35p is coloured purple. The structures
were generated with PyMol (http://pymol.sourceforge.net/).
The PDB coordinates used for the panels A and B are 1R5N and
1G6Y, respectively. See also Colour Insert.

S. cerevisiae

6.3.2 The [URE3] Trait

Nitrogen catabolism is finely regulated in . Ure2p, for

which the exact function is unknown, is involved in this process.

S. cerevisiae

24-28

In its soluble functional state, Ure2p is believed to interact in the
yeast cytosol with the “GATA” transcription factor Gln3p. Thus, Ure2p
prevents the entry of Gln3p into the nucleus where it transcribes a
number of genes among which includes

DAL5, the gene encoding the