Although there is an increasing interest in anhydrobiotic engineering using mammalian cells, little information is available on how they sense and respond to desiccation. Therefore we have investigated the effect of desiccation on stress signalling pathways and gene induction in human embryonic kidney cells (T-REx 293), in comparison with hyperosmolarity. A well-conserved signalling network involves mitogen-activated protein kinases (MAPKs), which modulate cellular response to a variety of stresses. Activation of JNK and p38 MAPKs by desiccation was shown by Western blotting to be rapid and comparable with that by osmotic stress. Gene induction by desiccation has been revealed by microarray and quantitative real-time PCR analyses.
Most of the highly induced genes were those encoding zinc finger transcriptional regulators and/or those involved in cell death and survival pathways, e.g. EGR1, EGR3, IER3, SNAI1, RASD1 and GADD45B, and were also induced by hypertonicity. Interestingly, however, the hyperosmotically responsive genes AR, BGT1 and SMIT, which encode proteins governing organic osmolyte accumulation to mitigate hyperosmotic water loss, were not significantly induced by desiccation. These data demonstrate that human cells can initiate a complex desiccation stress response distinct from, but overlapping with, that to hypertonic stress.
|Gene induction by desiccation stress in T-REx 293 cells (Huang & Tunnacliffe, 2005)|
Anhydrobiotic Engineering Research Topics:
Huang, Z. and Tunnacliffe, A. (2007) Desiccation response of mammalian cells: anhydrosignaling. Methods Enzymol. 428: 269-277
Huang, Z. and Tunnacliffe, A. (2006) Cryptobiosis, aging, and cancer: yin-yang balancing of signaling networks. Rejuv. Res. 9: 292-296
Huang, Z. and Tunnacliffe, A. (2005) Gene induction by desiccation stress in human cell cultures. FEBS Lett. 579: 4973-4977.
Huang, Z. and Tunnacliffe, A. (2004) Response of human cells to desiccation: comparison with hyperosmotic response. J. Physiol. 558: 181-191.