Biochemistry Graduate Seminar
Monday, October 26, 2009
Lecture at 4:30 p.m. in Burt Hall 114
Coffee at 4:15 p.m. in Chalmers 168
Rohit Kamat
Transcriptomic profile of different rhizotoxins in Arabidopsis thaliana
Plant response to extreme environmental elements is important for plant survival, adaptation and evolution. Stress factors like heavy metals, high salts, low oxygen levels, organic compounds, pathogens, freeze and draught conditions induce complex protective mechanisms in plants, some of which are common to all the stress-inducers with other pathways being highly specific. This paper discusses the expressed gene transcripts that predominate in the roots of the model plant Arabidopsis thaliana upon exposure to four known rhizotoxins- aluminium ions (Al), cadmium ions (Cd), copper ions (Cu) and sodium chloride salt (NaCl). Using microarray techniques and analysis of gene co-expression data, comparative gene expression transcripts for each stress inducer were generated. Common gene expression responses shared between the four stressors included glutathione-S-transferases, peroxidases, calcium-binding proteins, and trehalose-synthetase. Specific genes that were activated in response to the particular moiety included tolerance-inducing genes such as AtALMT1 (Al-activated malate transporter) in the Al-specific group, CRK10 (receptor like protein kinase) in the Cd-specific group, MT2A (Cu-detoxifying and binding metallothionein) in the Cu-specific group and DREB (dehydration responsive element binding protein) in the NaCl-specific group. Thus, identification and annotation of the genes expressed in the roots in response to external stress was shown.
This study will prove useful in our research of identifying the genes and enzymes that will get upregulated on exposure of Arabidopsis thaliana roots to similar stress inducers like synthetic dyes as well as understanding the mechanism by which plants respond to dyes.References:
Zhao,C-R., Ikka, T., Sawaki, Y., Kobayashi, Y., Suzuki, Y., Hibino, T., Sato, S., Sakurai, N., Shibata, D., and Koyama, H. Comparative transcriptomic characterization of aluminum, sodium chloride, cadmium and copper rhizotoxicities in Arabidopsis thaliana. BMC Plant Biology 9:32 (2009) doi: 10.1186/1471-2229-9-32.
Cosio, C., and Dunand C. Specific functions of class III peroxidase genes. Journal of Experimental Botany 60, 391-408 (2009)