Project description:The understanding of host responses to Tuber colonization would facilitate the exploration of symbiotic interactions and contribute to truffle artificial cultivation. T. indicum and T. panzhihuanense were selected to colonize Pinus armandii and Carya illinoinensis for a two-and-a-half-year symbiosis experiment in this study. The molecular response of host leaf to Tuber symbiosis was analyzed using RNA-seq. T. indicum and T. panzhihuanense both triggered the defense-related regulation in host leaf, like secondary metabolism, cell wall biogenesis, plant hormone signal transduction and plant-pathogen interaction, with different patterns in P. armandii and C. illinoinensis.
Project description:Several microorganisms have wide temperature growth range and versatility to tolerate large thermal fluctuations in diverse environments. To better understand thermal adaptation of psychrotrophs, Exiguobacterium sibiricum strain 255-15 was used, a psychrotrophic bacterium that grows from -5°C to 39°C. Its genome is approximately 3 Mb in size, has a GC content of 47.7% and includes 2,978 putative protein-encoding genes (CDS). The genome and transcriptome analysis along with the organism's known physiology was used to better understand its thermal adaptation. A total of about 27%, 3.2% and 5.2% of E. sibiricum strain 255-15 CDS spotted on the DNA microarray yielded differentially expressed genes in cells grown at -2.5°C, 10°C and 39°C, respectively, when compared to cells grown at 28°C. The hypothetical and unknown genes represented 10.6%, 0.89% and 2.3% of the CDS differentially expressed when grown at -2.5°C, 10°C and 39°C versus 28°C. The transcriptome analyses showed that E. sibiricum is constitutively adapted to cold temperatures since little differential gene expression was observed at growth temperatures of 10°C and 28°C, but at the extremities of its Arrhenius growth profile, namely -2.5°C and 39°C, much more differential gene expression occurred. The genes that responded were more typically associated with stress response. Keywords: stress response to cold and hot temperatures
