| Autor: |
Yalovsky, S., Trueblood, C. E., Callan, K. L., Narita, J. O., Jenkins, S. M., Rine, J., Gruissem, W. |
| Zdroj: |
Molecular and Cellular Biology; April 1997, Vol. 17 Issue: 4 p1986-1994, 9p |
| Abstrakt: |
Farnesyltransferase (FTase) is a heterodimeric enzyme that modifies a group of proteins, including Ras, in mammals and yeasts. Plant FTase α and β subunits were cloned from tomato and expressed in the yeast Saccharomyces cerevisiaeto assess their functional conservation in farnesylating Ras and a-factor proteins, which are important for cell growth and mating. The tomato FTase β subunit (LeFTB) alone was unable to complement the growth defect of ram1∆ mutant yeast strains in which the chromosomal FTase β subunit gene was deleted, but coexpression of LeFTBwith the plant α subunit gene (LeFTA) restored normal growth, Ras membrane association, and mating. LeFTB contains a novel 66-amino-acid sequence domain whose deletion reduces the efficiency of tomato FTase to restore normal growth to yeast ram1∆ strains. Coexpression of LeFTA and LeFTB in either yeast or insect cells yielded a functional enzyme that correctly farnesylated CaaX-motif-containing peptides. Despite their low degree of sequence homology, yeast and plant FTases shared similar in vivo and in vitro substrate specificities, demonstrating that this enzymatic modification of proteins with intermediates from the isoprenoid biosynthesis pathway is conserved in evolutionarily divergent eukaryotes. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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