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It appears that the Tor gene is involved in the response to
starvation via
nuclear localization.

Hong Li, Chi Kwan Tsang, Marcus Watkins, Paula G. Bertram
and X. F. Steven
Zheng

Nature 442, 1058-61 Published online 9 August 2006

Nutrient regulates Tor1 nuclear localization and association
with rDNA
promoter
... we show that Tor1 is dynamically distributed in
the cytoplasm and
nucleus in yeast. Tor1 nuclear localization is nutrient
dependent and
rapamycin sensitive: starvation or treatment with rapamycin
causes Tor1 to
exit from the nucleus. Tor1 nuclear localization is critical
for 35S rRNA
synthesis, but not for the expression of amino acid
transporters and
ribosomal protein genes. We show further that Tor1 is
associated with 35S
ribosomal DNA (rDNA) promoter chromatin in a rapamycin- and
starvation-sensitive manner; this association is necessary
for 35S rRNA
synthesis and cell growth. These results indicate that the
spatial
regulation of TOR complex 1 (TORC1) might be involved in
differential
control of its target genes. TOR is known as a classic
cytoplasmic kinase
that mediates the cytoplasm-to-nucleus signalling by
controlling the
localization of transcription factors. Our data indicate
that TOR might be
more intimately involved in gene regulation than previously
thought.