Isolation and characterization of an NTP-dependent 3'-exoribonuclease from mitochondria of Saccharomyces cerevisiae.
Year: 1993
Type: article
Abstract: RNA turnover in eukaryotes is thought to require 3'-exonuclease activity but so far no RNase with that specificity has been isolated from a eukaryote. We report here on the purification and characterization of a 3'-exoribonuclease isolated from the mitochondria of Saccharomyces cerevisiae. In vitro the purified enzyme displayed an absolute requirement of NTPs for activity. Each of the eight standard ribo- and deoxyribonucleotides supported activity with Km values ranging from 20 to 90 microM. The enzyme also displayed RNA-stimulated NTPase activity. The NTP-dependent enzyme cofractionated with three polypeptides of molecular masses 75,000, 90,000, and 110,000 daltons, although the native enzyme appears to have a molecular mass of 160,000 daltons predicted from the Stokes radius. The possible functions of this enzyme in vivo in the regulated decay of mitochondrial RNAs are discussed.
Source: Journal of Biological Chemistry
Authors: J. Min, R.M. Heuertz, H.P. Zassenhaus
Institution: Saint Louis University
Language: English
Topic: RNA Research and Splicing
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $3,430
OpenAlex ID: W1489832252
