[Overexpression of small heat-shock protein of endoplasmic reticulum enhances resistance of tomato to tunicamycin].
The accumulation of unfolded proteins in the endoplasmic reticulum (ER) lumen causes ER stress response in eukaryote cells, activates the unfolded protein response (UPR) and consequently induces the expression of ER-located molecular chaperones (such as BiP, calnexin, etc.). In this study, the full-length small heat-shock protein of endoplasmic reticulum cDNA (ER-sHSP) under the control of CaMV 35S promoter was introduced into tomato by Agrobacterium tumefactions mediated method (Fig. 1, Table 1). Overexpression of ER-sHSP enhanced the resistance of the transgenic plant to tunicamycin (Fig. 2, Table 2), an inducer of ER stress. Tunicamycin treatment induced an increase in mRNA level of BiP and calnexin in plant cell, but mRNAs of these two genes in transgenic plants were accumulated to a much smaller extent than those in non-transgenic plants (Fig. 3). These results indicated that ER-sHSP could alleviate the ER stress and may be involved in the UPR signal transmission pathway.
Zhao
Chun-Mei
CM
College of Life Sciences, Shandong Normal University, Jinan 250014, China.
Liu
Jian
J
D015152:Blotting, Northern; D015153:Blotting, Western; D004351:Drug Resistance; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D050888:Heat-Shock Proteins, Small / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D018551:Solanum lycopersicum / Q000187:drug effects* / Q000378:metabolism; D014415:Tunicamycin / Q000494:pharmacology*
D050888:Heat-Shock Proteins, Small; D014415:Tunicamycin