Differential regulation of the PanA and PanB proteasome-activating nucleotidase and 20S proteasomal proteins of the haloarchaeon Haloferax volcanii.

ABSTRACT: The halophilic archaeon Haloferax volcanii produces three different proteins (alpha1, alpha2, and beta) that assemble into at least two 20S proteasome isoforms. This work reports the cloning and sequencing of two H. volcanii proteasome-activating nucleotidase (PAN) genes (panA and panB). The deduced PAN proteins were 60% identical with Walker A and B motifs and a second region of homology typical of AAA ATPases. The most significant region of divergence was the N terminus predicted to adopt a coiled-coil conformation involved in substrate recognition. Of the five proteasomal proteins, the alpha1, beta, and PanA proteins were the most abundant. Differential regulation of all five genes was observed, with a four- to eightfold increase in mRNA levels as cells entered stationary phase. In para

SUBMITTER: Reuter CJ 

PROVIDER: S-EPMC524898 | biostudies-literature | 2004 Nov

REPOSITORIES: biostudies-literature