Heat shock responsiveness analysis of Athsp70b upstream region

Russian Journal of Plant Physiology (Impact Factor: 0.95). 09/2008; 55(5):629-638. DOI: 10.1134/S1021443708050063


A 1431-bp upstream fragment of Athsp70b was cloned via PCR amplification and expressed in onion epidermis by particle bombardment. Furthermore, the progressive deletions
of the Athsp70b upstream fragment linked to the β-glucuronidase (GUS) coding region were performed. Then, a stable GUS expression was analyzed
in tobacco BY2 cells and Arabidopsis. Our present results showed that about a 500-bp region upstream ATG of Athsp70b is suitable to confer heat inducibility to the GUS reporter gene in plants and around 116 bp contain nonperfect heat-sensitive element. This promoter responds to heat, salicylic
acid, and benzyladenine. GUS staining was mainly observed in the vascular tissues and root tips, implying that Athsp70b is related to water transportation.

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