[Genome-wide analysis of the LPAAT gene family in Gossypium raimondii and G. arboreum, and expression analysis of its orthologs in G. hirsutum].

Lysophosphatidic acid acyltransferase (LPAAT) which converts lysophosphatidic acid into phosphatidic acid is a key enzyme in biosynthesis pathway of lipid in plants. In this study, we identified 17 members of the LPAAT gene family from genomic data of G. raimondii-D5 and G. arboreum-A2. Analysis of gene structure, chromosome distribution and phylogenetic evolution of LPAAT genes in diploid Gossypium using bioinformatics approaches showed that these genes can be divided into distinct subfamilies based on the distance of their genetic relationship. Moreover, the gene structures were similar within LPAAT subfamily members. The amino acid sequences encoded by LPAAT family genes contained three conserved motifs, including ΦFPEGTR-G binding site and Φ-NHQS- ΦDΦΦ catalytic site. Phylogenetic analysis of LPAAT gene family demonstrated significant differences in evolution of LPAAT in different species. Finally, expression analysis of G. hirsutum ovules in different stages from RNA-seq and qRT-PCR data indicated that LPAAT gene may play a positive role in oil accumulation. Our studies facilitate understanding of the function of LPAAT gene family in Gossypium and selecting better LPAAT genes for further functional validation.