Peroxisomal proteins are post-translationally imported into peroxisomes after recognition by specific receptors. The best-defined peroxisomal targeting signal is a C-terminal tripeptide SKL. Different functional variants of this tripeptide have been defined, but mutants with a SKI sequence were recognized as being inefficiently targeted to peroxisomes. Recently, we have cloned a cDNA for the mouse hydroxyacid oxidase 1 (Hao1), a protein that seems to be localized in peroxisomes. Interestingly, the mouse Hao1 sequence comprises a C-terminal SKI tripeptide. We have analyzed the subcellular localization of Hao1 and tested whether its SKI sequence acts as a targeting signal. Ltk(-) and Cos-7 cells were transfected with vectors expressing a fusion protein of green fluorescence protein and Hao1, as well as mutants thereof. Targeting to peroxisomes of the fusion protein with the wild-type SKI sequence was highly selective and as complete as with the peroxisome-specific SKL sequence. By contrast, targeting was lost in a mutant with the sequence CKM. The data show that mammalian Hao1 is a peroxisomal protein and that the C-terminal sequence SKI acts as the targeting signal.
Peroxisomal targeting of mammalian hydroxyacid oxidase 1 requires the carboxy-terminal tripeptide SKI / S. Recalcati, E. Menotti, L. Kuhn. - In: JOURNAL OF CELL SCIENCE. - ISSN 0021-9533. - 114:9(2001 May), pp. 1625-1629.
|Titolo:||Peroxisomal targeting of mammalian hydroxyacid oxidase 1 requires the carboxy-terminal tripeptide SKI|
|Parole Chiave:||Hydroxyacid oxidase 1 ; Glycolate oxidase ; Peroxisome ; Protein import ; Targeting signal|
|Settore Scientifico Disciplinare:||Settore MED/04 - Patologia Generale|
|Data di pubblicazione:||mag-2001|
|Appare nelle tipologie:||01 - Articolo su periodico|