The β-amylase PbrBAM3 from pear (Pyrus betulaefolia) regulates soluble sugar accumulation and ROS homeostasis in response to cold stress

Liangyi Zhao; Tianyuan Yang; Caihua Xing; Huizheng Dong; Kaijie Qi; Junzhi Gao; Shutian Tao; Juyou Wu; Jun Wu; Shaoling Zhang; Xiaosan Huang

doi:10.1016/j.plantsci.2019.110184

The β-amylase PbrBAM3 from pear (Pyrus betulaefolia) regulates soluble sugar accumulation and ROS homeostasis in response to cold stress

Plant Sci. 2019 Oct:287:110184. doi: 10.1016/j.plantsci.2019.110184. Epub 2019 Jul 9.

Authors

Liangyi Zhao¹, Tianyuan Yang², Caihua Xing³, Huizheng Dong⁴, Kaijie Qi⁵, Junzhi Gao⁶, Shutian Tao⁷, Juyou Wu⁸, Jun Wu⁹, Shaoling Zhang¹⁰, Xiaosan Huang¹¹

Affiliations

¹ College of Horticulture, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: 2016104019@njau.edu.cn.
² College of Horticulture, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China; State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China. Electronic address: yangtianyuan2008@163.com.
³ College of Horticulture, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: 2015104018@njau.edu.cn.
⁴ College of Horticulture, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: 2017104017@njau.edu.cn.
⁵ College of Horticulture, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: qikaijie@njau.edu.cn.
⁶ College of Horticulture, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: 2017804152@njau.edu.cn.
⁷ College of Horticulture, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: toast@njau.edu.cn.
⁸ College of Horticulture, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: juyouwu@njau.edu.cn.
⁹ College of Horticulture, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: wujun@njau.edu.cn.
¹⁰ College of Horticulture, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: slzhang@njau.edu.cn.
¹¹ College of Horticulture, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: huangxs@njau.edu.cn.

PMID: 31481191
DOI: 10.1016/j.plantsci.2019.110184

Abstract

β-Amylase (BAM) is involved in sugar metabolism, but the role of BAM genes in cold tolerance remains poorly understood. Here, we report the identification and functional characterization of the chloroplast-localized BAM-encoding gene PbrBAM3 isolated from Pyrus betulaefolia. The transcript levels of PbrBAM3 were up-regulated under cold, dehydration and ABA, but repressed by maltose. Overexpression of PbrBAM3 in tobacco (Nicotiana tabacum) and pear (P. ussuriensis) conferred increased BAM activity, promoted starch degradation after chilling treatments and enhanced tolerance to cold. Under the chilling stress, the transgenic tobacco and P. ussuriensis exhibited lessened reactive oxygen species (ROS) generation, higher levels of antioxidant enzymes activity, and greater accumulation of soluble sugars (specially maltose) than the corresponding wild type plants. Taken together, these results demonstrate that PbrBAM3 plays an important role in cold tolerance, at least in part, by raising the levels of soluble sugars capable of acting as osmolytes or antioxidants.

Keywords: Antioxidant enzyme; Cold stress; Osmolyte; Reactive oxygen species (ROS); Starch degradation; β-amylase (BAM).

MeSH terms

Cold Temperature
Cold-Shock Response
Gene Expression Regulation, Plant*
Homeostasis
Plant Proteins / genetics
Plant Proteins / metabolism
Pyrus / enzymology*
Pyrus / genetics
Pyrus / physiology
Reactive Oxygen Species / metabolism*
Stress, Physiological
Sugars / metabolism*
beta-Amylase / genetics
beta-Amylase / metabolism*

Substances

Plant Proteins
Reactive Oxygen Species
Sugars
beta-Amylase