International Journal of Molecular Sciences (Dec 2022)

Genome-Wide Analysis of the <i>AAAP</i> Gene Family in <i>Populus</i> and Functional Analysis of <i>PsAAAP21</i> in Root Growth and Amino Acid Transport

  • Jiujun Du,
  • Changjian Du,
  • Xiaolan Ge,
  • Shuangshuang Wen,
  • Xinglu Zhou,
  • Lei Zhang,
  • Jianjun Hu

DOI
https://doi.org/10.3390/ijms24010624
Journal volume & issue
Vol. 24, no. 1
p. 624

Abstract

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The adventitious root (AR) is the basis for successful propagation by plant cuttings and tissue culture and is essential for maintaining the positive traits of a variety. Members of the amino acid/auxin permease (AAAP) gene family play indispensable roles in various plant metabolisms and have few studies on root growth and amino acid transport. In this study, with a systematic bioinformatics analysis of the Populus AAAP family, 83 PtrAAAPs were identified from Populus trichocarpa and grouped into 8 subfamilies. Subsequently, chromosomal distribution, genetic structure, cis-elements analysis, and expression pattern analysis of the AAAP family were performed and the potential gene AAAP21 regulating root development was screened by combining the results of RNA-Seq and QTL mapping. PsAAAP21 was proven as promoting root development by enhancing AR formation. Differentially expressed genes (DEGs) from RNA-seq results of overexpressing lines were enriched to multiple amino acid-related pathways, and the amino acid treatment to transgenic lines indicated that PsAAAP21 regulated amino acid transport, including tyrosine, methionine, and arginine. Analysis of the AAAP gene family provided a theoretical basis for uncovering the functions of AAAP genes. The identification of PsAAAP21 on root promotion and amino acid transport in Populus will help with breeding new woody plant species with strong rooting ability.

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