Beskrivelse
Functional genomics on an Arabidopsis family of putative lipid flippases Rosa L. López-Marqués, Lisbeth R. Poulsen and Michael G. Palmgren Department of Plant Biology, The Royal Veterinary and Agricultural University, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark In the plant Arabidopsis thaliana, a gene family of P4-TPases has been identified, named ALA1-12 (for Aminophospholipid ATPase 1 to 12). At least one of them, ALA1, has been demonstrated to encode an active aminophospholipid translocase (Gomès et al., 2003). Work with antisense mutants of ALA1 in Arabidopsis and functional complementation of a yeast strain lacking expression of the equivalent flippase (DRS2) showed a clear involvement of this protein in cold tolerance. However, as no other member of this family has been characterized so far, several questions remain open: - Are the other members of this family also aminophospholipid translocases? - Do the proteins have different substrate specifities or are they expressed in different tissues and/or at different times along development? On the other hand, it has also been proposed recently that several members of the cdc50/LEM3 protein family in yeast might be subunits of the P4-ATPases (Sato et al., 2004). For this reason, a bioinformatic search was done that allowed the identification of five homologues in Arabidopsis. A functional genomics approach is currently under way in order to characterise different members of the ALA family and the interactions with their possible subunits. Several representatives of both the ALA and the cdc50-like family have been cloned so far. Making use of a plasmid bearing a bidirectional galactose-inducible promoter (Gerik et al., 1997), the ala genes have been expressed, either separately or in combination with different cdc50-like genes, in yeast mutants lacking different combinations of the endogenous P4-ATPases. Preliminary results for these functional complementation experiments will be presented together with an overview of our future work. Gerik KJ, Gary SL and Burgers PMJ (1997) J. Biol. Chem. 272: 1256-1262. Gomès E, Jakobsen MK, Axelsen KB, Geisler M & Palmgren MG (2000). Plant Cell. 12: 2441-2453. Saito K, Fujimura-Kamada K, Furuta N, Kato U, Umeda M and Tanaka K (2004). Mol. Biol. Cell 15: 3418-3432.| Periode | 3 dec. 2005 |
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| Begivenhedstitel | PMT - Meeting of Young researchers |
| Begivenhedstype | Konference |
| Placering | Aix-En-Provence, FrankrigVis på kort |