|WANG, AI-QUIN - GUANGXI ACADEMY OF AGRICULTURAL SCIENCES|
|YE, XING-ZI - COLLABORATOR|
|HUANG, JING-LI - COLLABORATOR|
|NIU, JUN-QI - COLLABORATOR|
|LIU, MING - COLLABORATOR|
|YANG, LI-TAO - GUANGXI ACADEMY OF AGRICULTURAL SCIENCES|
|LI, YANG-RUI - COLLABORATOR|
Submitted to: Sugar Tech
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/1/2014
Publication Date: 3/20/2015
Publication URL: http://handle.nal.usda.gov/10113/63031
Citation: Wang, A., Ye, X., Huang, J., Niu, J., Liu, M., Pan, Y-B., Yang, L., Li, Y. 2015. Molecular cloning and functional analysis of an ethylene receptor gene from sugarcane (Saccharum spp.) by hormone and environmental stresses. Sugar Tech (Jan-Mar 2015) 17(1):22-30. DOI: 10.1007/s12355-014-0324-3.
Interpretive Summary: Ethephon, a commercial product of plant growth regulator ethylene, has been used to hasten sugarcane ripening process to increase sugar production. This study was conducted to investigate the molecular mechanism of how sugarcane plants respond to ethylene. Based on reported ethylene receptor, also known as ethylene response sensor or ERS, sequences from other plants, several pairs of PCR primers were designed for use to amplify related ERS sequences from sugarcane. The resulting sequences were analyzed by genetics software to assemble a complete gene sequence which was designated as GZ-ERS. The GZ-ERS gene has 2,243 base pairs and codes for a deduced protein of 633 amino acids. The amino acid sequence of this protein is 97, 96, and 91% identical to the reported ERS proteins of rice, corn, and sugarcane. Only a single GZ-ERS chromosome site is found in sugarcane. Using a molecular technique call real-time PCR, we found out that GZ-ERS is widely expressed in the vegetative tissues including leaves and internodes. However, the extent of expression of GZ-ERS differs in various tissues and at different developmental stages. In general, environmental stresses, such as cool temperature, drought, and darkness, can reduce gene expression. Results from this study will help understand gene expression regulation in sugarcane in general, but more specifically, how the sugarcane plants respond to ethephon treatment and environmental stresses. The GZ-ERS DNA sequence (Accession # GQ369007) is available from the GenBank database.
Technical Abstract: Ethylene receptor (ethylene response sensor, ERS) is the primary component involving in the ethylene biosynthesis and ethylene signal transduction pathway. In the present study, a GZ-ERS gene encoding ERS was cloned from a sugarcane cv. YL17 (Saccharum spp.) using RT-PCR and ligation-mediated PCR with primers designed based on conserved amino acid sequences of ERS from rice and corn. The GZ-ERS gene was 2,243 base pairs in length and coded for a polypeptide of 633 amino acid residues. The amino acid sequence of GZ-ERS encoded protein was 97, 96 and 91% identical to OS-ERS (AAX95525) of rice, ZmERS25 (AAR25567) of corn, and Sc-ERS (ACF60981) of a sugarcane cv. ROC22, respectively. Genomic Southern analysis using a GZ-ERS cDNA insert as the probe indicated the presence of a single copy of GZ-ERS gene per haploid sugarcane genome. Real-time PCR analysis showed that GZ-ERS was widely expressed in the vegetative tissues of sugarcane, and its expression in maturing internodes and leaf tissues was higher than in immature tissues. Furthermore, the expression level of GZ-ERS was the highest in maturing leaves, but very low in immature internodes. The GZ-ERS expression level in maturing leaves was enhanced by ethephon treatment, but was reduced under low temperature, drought, and dark conditions. The results from this study may help understand the regulation of gene expression in sugarcane and its responses to plant growth regulator ethephon and environmental stresses. As the sugarcane ERS family has multiple members, other members need to be isolated and characterized in future studies.