Identification of ABC transporter G subfamily in white lupin and functional characterization of L.albABGC29 in phosphorus use

Mehtab Muhammad Aslam; Muhammad Waseem; Qian Zhang; Wang Ke; Jianhua Zhang; Weifeng Xu

doi:10.1186/s12864-021-08015-0

Identification of ABC transporter G subfamily in white lupin and functional characterization of L.albABGC29 in phosphorus use

BMC Genomics. 2021 Oct 6;22(1):723. doi: 10.1186/s12864-021-08015-0.

Authors

Mehtab Muhammad Aslam^{1

2}, Muhammad Waseem³, Qian Zhang², Wang Ke², Jianhua Zhang^{1

4}, Weifeng Xu⁵

Affiliations

¹ College of Agriculture, Yangzhou University, Yangzhou, 225009, China.
² Joint International Research Laboratory of Water and Nutrient in Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
³ College of Horticulture, South China Agricultural University, Guangzhou, 510642, China.
⁴ Department of Biology, Hong Kong Baptist University, Stake Key Laboratory of Agrobiotechnology and Chinese University of Hong Kong, Kowloon Tong, Hong Kong.
⁵ Joint International Research Laboratory of Water and Nutrient in Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, China. wfxu@fafu.edu.cn.

Abstract

Background: White lupin (Lupinus albus) is a leguminous crop with elite adaptive ability in phosphorus-deficient soil and used as a model plant for studying phosphorus (P) use. However, the genetic basis of its adaptation to low P (LP) remains unclear. ATPase binding cassette (ABC) transports G subfamily play a crucial role in the transportation of biological molecules across the membrane. To date, identification of this subfamily has been analyzed in some plants, but no systematic analysis of these transporters in phosphorus acquisition is available for white lupin.

Results: This study identified 66 ABCG gene family members in the white lupin genome using comprehensive approaches. Phylogenetic analysis of white lupin ABCG transporters revealed six subclades based on their counterparts in Arabidopsis, displaying distinct gene structure and motif distribution in each cluster. Influences of the whole genome duplication on the evolution of L.albABCGs were investigated in detail. Segmental duplications appear to be the major driving force for the expansion of ABCGs in white lupin. Analysis of the Ka/Ks ratios indicated that the paralogs of the L.albABCG subfamily members principally underwent purifying selection. However, it was found that L.albABCG29 was a result of both tandem and segmental duplications. Overexpression of L.albABCG29 in white lupin hairy root enhanced P accumulation in cluster root under LP and improved plant growth. Histochemical GUS staining indicated that L.albABCG29 expression increased under LP in white lupin roots. Further, overexpression of L.albABCG29 in rice significantly improved P use under combined soil drying and LP by improving root growth associated with increased rhizosheath formation.

Conclusion: Through systematic and comprehensive genome-wide bioinformatics analysis, including conserved domain, gene structures, chromosomal distribution, phylogenetic relationships, and gene duplication analysis, the L.albABCG subfamily was identified in white lupin, and L.albABCG29 characterized in detail. In summary, our results provide deep insight into the characterization of the L.albABCG subfamily and the role of L.albABCG29 in improving P use.

Keywords: ABCG subfamily; Duplication; Phosphorus; Rice; White lupin.

MeSH terms

ATP-Binding Cassette Transporters / genetics
Computational Biology
Lupinus* / genetics
Phosphorus
Phylogeny

Substances

ATP-Binding Cassette Transporters
Phosphorus