Biochemical and structural characterization of yeast exosome interactions with regulatory proteins of their activity

• Grant number: 12/50196-6
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Effective date (Start): June 01, 2012
• Effective date (End): December 31, 2015
• Field of knowledge: Biological Sciences - Biochemistry - Biochemistry of Microorganisms
• Principal Investigator: Carla Columbano de Oliveira
• Grantee: Fernando Alexis Gonzales Zubiate
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 10/51842-3 - Structural study of protein components of the exosome and some of its regulatory factors from Archaea and yeast, AP.TEM

Abstract

The exosome is a protein complex formed by eleven subunits, which is present in archaea and eukaryotes, has exoribonucleolytic activity in the 3'-5' direction, and is involved in processing and/or degradation of all kinds of RNA. Our laboratory has been working on the functional and structural characterization of the archaeal and yeast exosomes, and has shown the structure of the Pyrococcus complex, determined by SAXS and crystallography (Ramos et al., 2006; Navarro et al., 2008). We have also obtained a model for the general structure of the yeast complex based on subunits interaction data (Luz et al., 2007). The exosome is involved in different pathways of RNA processing and degradation, and because it interacts with single-stranded RNA in a non-sequence specific manner, it is currently predicted that the control of exosome activity is done by proteins that interact both with RNA and the exosome. The study of exosome regulatory factors in our laboratory has identified proteins modulating the activity of the complex both in Pyrococcus abyssi and in yeast (Luz et al., 2010; Granato et al., 2008; Santos et al., 2011). The yeast proteins Nop53p and Nop8p have been characterized as exosome regulatory factors in our laboratory. Both these proteins are localized to the nucleolus and control the exosome activity during pre-rRNA processing, although in different ways. Whereas Nop53p activates the exosome, Nop8p inhibits its activity (Granato et al., 2008; Santos et al., 2011). This work aims at the functional and structural characterization of the role these regulatory proteins play in the control of the exosome activity and the effects of these interactions on the complex structure. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

GONZALES-ZUBIATE, FERNANDO A.; OKUDA, ELLEN K.; DA CUNHA, JULIA P. C.; OLIVEIRA, CARLA COLUMBANO. Identification of karyopherins involved in the nuclear import of RNA exosome subunit Rrp6 in Saccharomyces cerevisiae. Journal of Biological Chemistry, v. 292, n. 29, p. 12267-12284, JUL 21 2017. (12/50196-6, 10/51842-3, 15/06477-9)