Abstract
Loss of synaptophysin, one of the major synaptic vesicle membrane proteins, is surprisingly well tolerated in knockout mice. To test whether compensatory gene transcription accounts for the apparent lack of functional deficiencies, comparative transcriptome analyses were carried out. The retina was selected as the most suitable tissue since morphological alterations were observed in mutant photoreceptors, most notably a reduction of synaptic vesicles and concomitant increase in clathrin-coated vesicles. Labeled cRNA was prepared in triplicate from retinae of age- and sex-matched wild-type and mutant litter mates and hybridized to high-density microarray chips. Only three differentially expressed RNAs were identified in this way, one of which was synaptophysin. Further validation by quantitative RT-PCR could only corroborate the results for the latter. We therefore conclude that, despite the distinct morphological phenotype, no significant changes in gene expression are detectable in synaptophysin-deficient animals and that therefore compensatory mechanisms are either pre-existent and/or act at the posttranscriptional level.
References
Nov 3, 1989·Cell·R E LeubeW W Franke
Nov 20, 1987·Science·T C SüdhofR Jahn
Jun 1, 1985·Proceedings of the National Academy of Sciences of the United States of America·R JahnP Greengard
Jul 1, 1985·Cell·B Wiedenmann, W W Franke
Dec 1, 1994·The Journal of Cell Biology·R E LeubeB Wiedenmann
Feb 1, 1995·The Biochemical Journal·P WashbourneC Montecucco
Dec 1, 1995·Cell and Tissue Research·L G Eshkind, R E Leube
Apr 10, 1996·Experimental Cell Research·U LeimerR E Leube
May 14, 1996·Proceedings of the National Academy of Sciences of the United States of America·H T McMahonT C Südhof
Oct 27, 1999·European Journal of Cell Biology·A BecherG Ahnert-Hilger
Dec 14, 1999·Neuron·R JanzV Y Bolshakov
Jan 6, 2000·Nature Cell Biology·C ThieleW B Huttner
May 24, 2000·Proceedings of the National Academy of Sciences of the United States of America·C DalyR Llinás
Nov 21, 2001·European Journal of Cell Biology·B HinzG Ahnert-Hilger
Dec 18, 2001·Neuroscience·I Spiwoks-BeckerR E Leube
Jan 10, 2002·The Journal of Biological Chemistry·Christopher Daly, Edward B Ziff
Mar 15, 2002·International Review of Cytology·Kirsten HübnerRudolf E Leube
Jun 26, 2004·Annual Review of Neuroscience·Thomas C Sudhof
Dec 22, 2004·Nature Reviews. Neuroscience·Silvio O Rizzoli, William J Betz