Find in Library

Brown alga <i>Ectocarpus</i> sp. belongs to Phaeophyceae, a class of macroalgae that evolved complex multicellularity. <i>Ectocarpus</i> sp. is a dominant seaweed in temperate regions, abundant mostly in the intertidal zones, an environment with high levels of abiotic stresses. Previous transcriptomic analysis of <i>Ectocarpus</i> sp. revealed several genes consistently induced by various abiotic stresses; one of these genes is <i>Esi0017_0056</i>, which encodes a protein with unknown function. Bioinformatics analyses indicated that the protein encoded by <i>Esi0017_0056</i> is soluble and monomeric. The protein was successfully expressed in <i>Escherichia coli,</i><i>Arabidopsis thaliana</i> and <i>Nicotiana benthamiana.</i> In <i>A. thaliana</i> the gene was expressed under constitutive and stress inducible promoters which led to improved tolerance to high salinity and temperature stresses. The expression of several key abiotic stress-related genes was studied in transgenic and wild type <i>A. thaliana</i> by qPCR. Expression analysis revealed that genes involved in ABA-induced abiotic stress tolerance, K⁺ homeostasis, and chaperon activities were significantly up-regulated in the transgenic line. This study is the first report in which an unknown function <i>Ectocarpus</i> sp. gene, highly responsive to abiotic stresses, was successfully expressed in <i>A. thaliana</i>, leading to improved tolerance to salt and temperature stress.