title: Identification of two novel type 1 peroxisomal targeting signals in Arabidopsis thaliana.
abstract: Peroxisomes lack their own genetic material and must therefore import proteins encoded by genes in the nucleus. Amino acids within these proteins serve as targeting signals: they direct the delivery of the proteins to the organelle. The majority of soluble proteins destined for the peroxisomal matrix utilize a type 1 peroxisomal targeting signal (PTS1): a C-terminal tripeptide that follows the pattern small/basic/hydrophobic. We have discovered two new C-terminal tripeptides that target proteins to peroxisomes in Arabidopsis thaliana. The tripeptides PSL and KRR do not fit the major PTS1 consensus but cause green fluorescent protein to accumulate in peroxisomes of stably transformed Arabidopsis. We have identified forty-one proteins in the Arabidopsis genome that also bear these tripeptides at their C-termini and may therefore be peroxisomal.
authors.affiliation: Department of Biology, California State University Northridge, 18111 Nordhoff St., Northridge, CA 91330-8303, USA.
authors.forename: Rigoberto A
authors.initials: RA
authors.lastname: Ramirez
authors.affiliation: Department of Biology, California State University Northridge, 18111 Nordhoff St., Northridge, CA 91330-8303, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Espinoza
authors.affiliation: Department of Biology, California State University Northridge, 18111 Nordhoff St., Northridge, CA 91330-8303, USA. Electronic address: ernest.kwok@csun.edu.
authors.forename: Ernest Y
authors.initials: EY
authors.lastname: Kwok
mesh_terms: D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism; D020675:Peroxisomes / Q000378:metabolism*; D021381:Protein Transport; D018160:Receptors, Cytoplasmic and Nuclear
chemical_list: D029681:Arabidopsis Proteins; D018160:Receptors, Cytoplasmic and Nuclear
keywords: Arabidopsis thaliana; PTS1; Peroxisome; Protein targeting