Cloning and functional expression of Rpn1, a regulatory-particle non-ATPase subunit 1, of proteasome from Trypanosoma cruzi

Citation
Cb. Zou et al., Cloning and functional expression of Rpn1, a regulatory-particle non-ATPase subunit 1, of proteasome from Trypanosoma cruzi, MOL BIOCH P, 110(2), 2000, pp. 323-331
Citations number
36
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Microbiology
Journal title
MOLECULAR AND BIOCHEMICAL PARASITOLOGY
ISSN journal
0166-6851 → ACNP
Volume
110
Issue
2
Year of publication
2000
Pages
323 - 331
Database
ISI
SICI code
0166-6851(200010)110:2<323:CAFEOR>2.0.ZU;2-W
Abstract
Non-lysosomal protein degradation in eukaryotic cells involves a proteolyti c complex referred to as 26S proteasome that consists of a 20S core particl e and one or two 19S regulatory particles. We have cloned the gene RPN1 enc oding Rpn1 (regulatory-particle non-ATPase subunit 1), one of the largest s ubunits of proteasome, from Trypanosoma cruzi. It contains 2712 bp and enco des 904 amino acid residues with a calculated molecular mass of 98.2 kDa an d an isoelectric point of 5.2. The predicted amino acid sequence of the try panoomatid Rpn1 shares 39.0 and 32.0% overall identities with human Rpn1 an d Saccharomyces cerevisiae Nas1 (non-ATPase subunit 1), an Rpn1 homolog, re spectively, while the sequence identities among T. cruzi, Plasmodium falcip arum, and Entamoeba histolytica Rpn1 are approximately 30%. T. cruzi Rpn1 c ontains nine repeats of about 36 amino acid residues conserved in Rpn1s fro m various organisms. TT. cruzi RPN1 is located on the 2300- and 1900-kb chr omosomal DNA, displays a putative allelic variation as RPN1-1 and RPN1-2 wi th 98.8% identity between these two putative gene products, and is transcri bed from both alleles at a comparable level throughout the three developmen tal stages of the parasite, epimastigotes, trypomastigotes, and amastigotes . The expression of the trypanosomatid Rpn1 in the temperature-sensitive na s1 yeast mutant rescued the growth defect at the restrictive temperature, i ndicating that Rpn1 functions as a Nas1 and probably assembles into the 19S regulatory particle of the yeast 26S proteasome. (C) 2000 Elsevier Science B.V. All rights reserved.