Characterization of Rny1, the Saccharomyces cerevisiae member of the T2 RNase family of RNases: Unexpected functions for ancient enzymesProceedings of the National Academy of Sciences (2001)
The T2 family of nonspecific endoribonucleases (EC 188.8.131.52) is a
widespread family of RNases found in every organism examined
thus far. Most T2 enzymes are secretory RNases and therefore are
found extracellularly or in compartments of the endomembrane
system that would minimize their contact with cellular RNA.
Although the biological functions of various T2 RNases have been
postulated on the basis of enzyme location or gene expression
patterns, the cellular roles of these enzymes are generally unknown.
In the present work, we characterized Rny1, the only T2
RNase in Saccharomyces cerevisiae. Rny1 was found to be an active,
secreted RNase whose gene expression is controlled by heat shock
and osmotic stress. Inactivation of RNY1 leads to unusually large
cells that are temperature-sensitive for growth. These phenotypes
can be complemented not only by RNY1 but also by both structurally
related and unrelated secretory RNases. Additionally, the
complementation depends on RNase activity. When coupled with
a recent report on the effect of specific RNAs on membrane
permeability [Khvorova, A., Kwak, Y-G., Tamkun, M., Majerfeld, I.
& Yarus, M. (1999) Proc. Natl. Acad. Sci. USA 96, 10649–10654], our
work suggests an unexpected role for Rny1 and possibly other
secretory RNases. These enzymes may regulate membrane permeability
or stability, a hypothesis that could present an alternative
perspective for understanding their functions.
Citation InformationGustavo C Macintosh, Pauline A. Bariola, Ed Newbigin and Pamela J. Green. "Characterization of Rny1, the Saccharomyces cerevisiae member of the T2 RNase family of RNases: Unexpected functions for ancient enzymes" Proceedings of the National Academy of Sciences Vol. 98 Iss. 3 (2001) p. 1018 - 1023
Available at: http://works.bepress.com/gustavo-macintosh/10/