Background
Cotton (
Gossypium
spp.) is the most important natural fiber crop worldwide, and cottonseed oil is its most important byproduct. Phospholipid: diacylglycerol acyltransferase (PDAT) is important in TAG biosynthesis, as it catalyzes the transfer of a fatty acyl moiety from the
sn
-2 position of a phospholipid to the
sn
-3 position of
sn
-1, 2-diacylglyerol to form triacylglycerol (TAG) and a lysophospholipid. However, little is known about the genes encoding PDATs involved in cottonseed oil biosynthesis.
Results
A comprehensive genome-wide analysis of
G. hirsutum
,
G. barbadense
,
G. arboreum
, and
G. raimondii
herein identified 12, 11, 6 and 6
PDAT
s, respectively. These genes were divided into 3 subfamilies, and a PDAT-like subfamily was identified in comparison with dicotyledonous
Arabidopsis
. All GhPDATs contained one or two LCAT domains at the C-terminus, while most GhPDATs contained a preserved single transmembrane region at the N-terminus. A chromosomal distribution analysis showed that the 12
GhPDAT
genes in
G. hirsutum
were distributed in 10 chromosomes. However, none of the
GhPDATs
was co-localized with quantitative trait loci (QTL) for cottonseed oil content, suggesting that their sequence variations are not genetically associated with the natural variation in cottonseed oil content. Most
GhPDATs
were expressed during the cottonseed oil accumulation stage. Ectopic expression of
GhPDAT1d
increased
Arabidopsis
seed oil content.
Conclusions
Our comprehensive genome-wide analysis of the cotton
PDAT
gene family provides a foundation for further studies into the use of
PDAT
genes to increase cottonseed oil content through biotechnology.
Electronic supplementary material
The online version of this article (10.1186/s12864-019-5728-8) contains supplementary material, which is available to authorized users.