The multicatalytic proteinase (prosome) is ubiquitous from eukaryotes to archaebacteria

Abstract

From the thermoacidophilic archaebacterium, Thermopiasma acidophilum, a proteolytically active particle has been isolated which is almost identical in size. and shape with the multicatalytic proteinase (prosome) from rat. This result indicates that prosomes have been developed early in evolution and that they possibly serve functions common to all living cells.

Cloning and sequencing of the gene encoding the large (α‐) subunit of the proteasome from Thermoplasma acidophilum

“…1), giving rise to a molecular weight of 25870. This ts in good agreement with the apparent molecular mass of 27 kDa obtained by SDS-PAGE [7].…”

“…It is found in all ¢ukaryotes from yeast to man [2]. It is widely accepted now that the proteasome or multicataiytic proteinase (3] is identical to the prosome (4,5], a 19=20 S nbonucleotprote~n supposed to be revolved m the regulation of gene expression, While there ts no ewdence for the ex,stence of proteasomes ,n eubacterm [2,6], we have recently isolated proteasomes from the thelmoac~dophilic archaebactermm Thermoplasma actdophdum [7]. Contrary to the complex subumt com- Abbrewattons, crl, mutatlon encoding cyclohexlmzde and temperature sensmw, lethality, HPLC, high-performance hquld chromatography, sell *, w,ldtype allele of sell/SCLI-I, mutant allele of sell, dom,nant suppressor of crl3 temperature-sensitive lethality, SDS.PAGE, sodlum dodecyl sulfate pob'acr>lamlde gel electrophoreszs, TFA, trifluoroaceuc acid, YC, yeast component of the proteasome dtg|tal ~mage processing (7,8].…”

Identification and characterization of an activated 20S proteasome in Trypanosoma brucei

“…Each ring is composed of seven subunit proteins and a feature which is conserved from the prokaryotes to the eukaryotes [16]. However, the subunit compositions are subjected to dramatic modifications in the course of evolution from as simple as two types of subunits (a and (3) in the archaebacterium Thermoplasma acidophilum [17] to as many as 7 different eland 7 different |3-subunits in higher eukaryotes [16]. The construction of T. acidophilum 20S proteasome in the OC7P7P7OI7 form was recently confirmed by X-ray crystallography [18].…”

Structure and RNA content of the prosomes

“…in the latter, they are associated with the Intermediate Filaments of the cytoskeleton [10], Their most outstanding physical property is their high molecular weight. The individual particle is a multisubunit complex consisting o1" a variable set of 15-30 polypeptide~ with molecular ~ ma~es of [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36]. Although the presence of a small RNA wl, th a length or" S0--120 t~ucleotides i~ well dt~cu-mented tbr prosomes [!,6,7,14], controversy still exists over its quantity, The original {over-) estimation of 15% was based on a density of !,31 g/cm -~ and Spirin's *We use here the terni "Prosomc' introduced by our laboratory (Schmid et al,, 1984) tbr the then unknown l~Wt;cle and, speaking of its protease activity, the tema "Multicatatytic Proteinas¢ or MCP' according to the recommendation of the group of enzymologists (Dahlman ct aL, 1988; and Orlo~,ski and Wi|k, 1988), in pn:ferencu to the term "Proteasome" sug, gested by Arrigo et al, 11988} [I--4].…”