title: The Promoter of AtUSP Is Co-regulated by Phytohormones and Abiotic Stresses inArabidopsis thaliana.
abstract: Universal stress proteins (USPs) are known to be expressed in response to various abiotic stresses in a wide variety of organisms, such as bacteria, archaebacteria, protists, algae, fungi, plants, and animals. However, in plants, biological function of most of the USPs still remains obscure. In the present study,ArabidopsisUSP gene (AtUSP) showed induction in response to abscisic acid (ABA) and various abiotic stressesviz. heat, dehydration, salt, osmotic, and cold stresses. Additionally,in silicoanalysis ofAtUSPpromoter identified severalcis-elements responsive to phytohormones and abiotic stresses such as ABRE, ERE, DRE, and HSE, etc. To functionally validate theAtUSPpromoter, the 1115 bp region of promoter was characterized under phytohormone and abiotic stress treatments. Deletion analysis of promoter was carried out by cloning the full length promoter (D0) and its three 5' deletion derivatives, D1 (964 bp), D2 (660 bp), and D3 (503 bp) upstream of the β-glucuronidase (GUS) reporter gene, which were then stably transformed inArabidopsisplants. TheAtUSPpromoter (D0) showed minimal activity under non-stress conditions which was enhanced in response to phytohormone treatments (ABA and ACC) and abiotic stresses such as dehydration, heat, cold, salt, and osmotic stresses. The seedlings harboring D1 and D2 deletion fragments showed constitutive GUS expression even under control condition with increased activity almost under all the treatments. However, D3 seedlings exhibited complete loss of activity under control condition with induction under ACC treatment, dehydration, heat, oxidative, salt, and osmotic stresses. Thus, present study clearly showed thatAtUSPpromoter is highly inducible by phytohormones and multiple abiotic stresses and it can be exploited as stress inducible promoter to generate multi-stress tolerant crops with minimal effects on their other important traits.
authors.affiliation: Council of Scientific and Industrial Research - Institute of Himalayan Bioresource TechnologyPalampur, India; Academy of Scientific and Innovative ResearchNew Delhi, India.
authors.forename: Monika
authors.initials: M
authors.lastname: Bhuria
authors.affiliation: Council of Scientific and Industrial Research - Institute of Himalayan Bioresource TechnologyPalampur, India; Academy of Scientific and Innovative ResearchNew Delhi, India.
authors.forename: Parul
authors.initials: P
authors.lastname: Goel
authors.affiliation: Council of Scientific and Industrial Research - Institute of Himalayan Bioresource TechnologyPalampur, India; Academy of Scientific and Innovative ResearchNew Delhi, India.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Kumar
authors.affiliation: Council of Scientific and Industrial Research - Institute of Himalayan Bioresource TechnologyPalampur, India; Academy of Scientific and Innovative ResearchNew Delhi, India.
authors.forename: Anil K
authors.initials: AK
authors.lastname: Singh
keywords: Arabidopsis; AtUSP; abiotic stress; deletion analysis; phytohormones; promoter; universal stress protein