Asagi, K. , Oka, T. , Arao, K. , Suzuki, I. , Thakur, M. K. , Izumi, K. , and Natori, Y. 1998. Purification, characterization and differentiation-dependent expression of a perchloric acid soluble protein from rat kidney. Nephron 79: 80–90.
The protein was shown to consist of two identical subunits with a molecular mass of 14 kDa. By immunoscreening with the rabbit antisera against the protein, a cDNA encoding the protein was cloned and sequenced. The cDNA contained an open reading frame of 411 base pairs encoding a 136-amino acid protein with a molecular mass of 14,149 Da. The deduced amino acid sequence was completely identical with that constructed from all of the above peptides. Interestingly, the perchloric acid-soluble protein.
Rat liver perchloric acid-soluble protein (L-PSP)1 is a 136-amino acid protein that inhibits protein synthesis (1). Oka et al. (1) demonstrated that L-PSP, when added to a rabbit reticulocyte cell-free system, causes inhibition of a biphasic kinetic nature and also leads to the disaggregation of polysomes. This would be similar to the mode of inhibition of translation by the heme-regulated eukaryotic initiation factor 2a kinase (2) (however, see our results below).