IC4R004-Microarray-2012-22827941

Project Title

• Microarray analysis reveals overlapping and specific transcriptional responses to different plant hormones in rice

The Background of This Project

• Hormones govern almost every aspect of plant life cycle from germination to seed development. Several molecular genetics studies have demonstrated the crucial role of various hormones in plant growth and development processes. The analyses of mutants with altered hormone biosynthesis and signaling have revealed the role of auxin, brassinosteroid, cytokinin and gibberellin in cell expansion along the longitudinal axes and ethylene along the transverse axes. Abscisic acid acts antagonistically on plant growth and is majorly involved in abiotic stress responses. Jasmonic acid and salicylic acid are involved in plant defense responses against pathogens.
• Most of our knowledge in hormone biology is based on the work done in Arabidopsis. Only a few studies have been performed to show the effect of different hormones at whole genome level in crop plant rice. 8,17-19 Further, the comparison of transcriptional responses of different plant hormones is also not available in rice. In this study, we performed microarray analy- sis in rice to study the effect of different hormones, including auxin, cytokinin, abscisic acid, ethylene, salicylic acid and jas- monic acid, on gene expression at whole genome level. We further examined the overlap in the transcriptional responses to different hormones and identified several hormone-specific marker genes.

Plant Materials & Treatment

• Plant material and hormone treatments. Rice (Oryza sativa subspecies indica variety IR64) seeds were treated and grown as described previously. 2 Different hormone treatments were given to the 7-d-old light-grown rice seedlings as described. 8,10 The seedlings were transferred to the beakers containing 50 μM solution of indole-3-acetic acid (auxin) and benzyl aminopurine (cytokinin) and 100 μM solution of abscisic acid, 1-aminocyclopropane-1-carboxylic acid (ethylene derivative), salicylic acid and jasmonic acid for hormone treatments. The seedlings were kept in respective solutions for 3 h, at 28 ± 1°C before harvesting. The seedlings kept in water for 3 h, at 28 ± 1°C served as control. At least three independent biological replicates of each tissue sample were harvested.

Labs working on this Project

• National Institute of Plant Genome Research (NIPGR); Aruna Asaf Ali Marg; New Delhi, India

Corresponding Author

Mukesh Jain (email: mjain@nipgr.res.in )