tailieunhanh - báo cáo khoa học: "Transcriptional analysis of cell growth and morphogenesis in the unicellular green alga Micrasterias (Streptophyta), with emphasis on the role of expansin"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Transcriptional analysis of cell growth and morphogenesis in the unicellular green alga Micrasterias (Streptophyta), with emphasis on the role of expansin | Vannerum et al. BMC Plant Biology 2011 11 128 http 1471-2229 11 128 BMC Plant Biology RESEARCH ARTICLE Open Access Transcriptional analysis of cell growth and morphogenesis in the unicellular green alga Micrasterias Streptophyta with emphasis on the role of expansin 23 23 4 23 Katrijn Vannerum Marie JJ Huysman Riet De Rycke Marnik Vuylsteke Frederik Leliaert Jacob Pollier 5 1 Ursula Lutz-Meindl Jeroen Gillard Lieven De Veylder Alain Goossens Dirk Inzé and Wim Vyverman Abstract Background Streptophyte green algae share several characteristics of cell growth and cell wall formation with their relatives the embryophytic land plants. The multilobed cell wall of Micrasterias denticulata that rebuilds symmetrically after cell division and consists of pectin and cellulose makes this unicellular streptophyte alga an interesting model system to study the molecular controls on cell shape and cell wall formation in green plants. Results Genome-wide transcript expression profiling of synchronously growing cells identified 107 genes of which the expression correlated with the growth phase. Four transcripts showed high similarity to expansins that had not been examined previously in green algae. Phylogenetic analysis suggests that these genes are most closely related to the plant EXPANSIN A family although their domain organization is very divergent. A GFP-tagged version of the expansin-resembling protein MdEXP2 localized to the cell wall and in Golgi-derived vesicles. Overexpression phenotypes ranged from lobe elongation to loss of growth polarity and planarity. These results indicate that MdEXP2 can alter the cell wall structure and thus might have a function related to that of land plant expansins during cell morphogenesis. Conclusions Our study demonstrates the potential of M. denticulata as a unicellular model system in which cell growth mechanisms have been discovered similar to those in land plants. Additionally evidence