This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Singh, K K Articles by Lewin, A S Search for Related Content PubMed PubMed Citation Articles by Singh, K K Articles by Lewin, A S

 Previous Article  |  Next Article 

Mol Cell Biol. 1992 December; 12(12): 5593-5599

Alternative topogenic signals in peroxisomal citrate synthase of Saccharomyces cerevisiae.

K K Singh, G M Small and A S Lewin

Department of Immunology and Medical Microbiology, College of Medicine, University of Florida, Gainesville 32601.

ABSTRACT

The tripeptide serine-lysine-leucine (SKL) occurs at the carboxyl terminus of many peroxisomal proteins and serves as a peroxisomal targeting signal. Saccharomyces cerevisiae has two isozymes of citrate synthase. The peroxisomal form, encoded by CIT2, terminates in SKL, while the mitochondrial form, encoded by CIT1, begins with an amino-terminal mitochondrial signal sequence and ends in SKN. We analyzed the importance of SKL as a topogenic signal for citrate synthase, using oleate to induce peroxisomes and density gradients to fractionate organelles. Our experiments revealed that SKL was necessary for directing citrate synthase to peroxisomes. C-terminal SKL was also sufficient to target a leaderless version of mitochondrial citrate synthase to peroxisomes. Deleting this tripeptide from the CIT2 protein caused peroxisomal citrate synthase to be missorted to mitochondria. These experiments suggest that the CIT2 protein contains a cryptic mitochondrial targeting signal.

---

Mol Cell Biol. 1992 December; 12(12): 5593-5599

This article has been cited by other articles:

• Lee, J. G., Lee, Y. J., Lee, C. H., Maeng, P. J. (2006). Mutational and functional analysis of the cryptic N-terminal targeting signal for both mitochondria and peroxisomes in yeast peroxisomal citrate synthase cit2p.. J Biochem 140: 121-133 [Abstract] [Full Text]  
• Karpichev, I., Small, G. (2000). Evidence for a novel pathway for the targeting of a Saccharomyces cerevisiae peroxisomal protein belonging to the isomerase/hydratase family. J. Cell Sci. 113: 533-544 [Abstract]  
• McAlister-Henn, L., Steffan, J. S., Minard, K. I., Anderson, S. L. (1995). Expression and Function of a Mislocalized Form of Peroxisomal Malate Dehydrogenase (MDH3) in Yeast. J. Biol. Chem. 270: 21220-21225 [Abstract] [Full Text]