Sub-Functionalization in Rice Gene Families with Regulatory Roles in Abiotic Stress Responses

ABSTRACT

Plants have developed intricate mechanisms to overcome abiotic stresses. The process of signal perception and activation of signaling cascades involves a large number of factors and molecules belonging to diverse classes of gene families. In comparison to animals, plants harbor larger multigene families along with the occurrence of plant-specific ones. Gene families with abiotic-stress-responsive members were analyzed and categorized into classes such as transcription factors, signal transduction components, transporters, epigenetic regulators, and other regulatory components. The number of members, phylogeny, family expansion, domain composition, subcellular localization, and expression profiling during varied abiotic stresses have been summarized. Candidate genes from families, functionally characterized for abiotic stress responses, have been described. Based on our compilation, the expansion of abiotic-stress-responsive gene families in rice has occurred via segmental and tandem duplication events to accommodate sub-functionalization needed for regulating diverse abiotic stress responses at expression, localization, and functional levels. The information documented here can be further utilized as a primer for selecting candidate genes for improvement of rice yield under abiotic stresses.

KEYWORDS:

• Abiotic stress
• epigenetics
• gene duplication
• gene families
• gene regulation
• oxidative stress
• rice
• salt stress
• signal transduction
• sub-functionalization
• transcription factors
• water-deficit stress

Acknowledgments

The authors are thankful to Prof. Ashwani Pareek, Jawaharlal Nehru University, New Delhi, for critical reading of manuscript and constructive suggestions.

Funding

Our research on abiotic stress in rice is supported by the Department of Biotechnology and the Department of Science and Technology, Government of India.