Abstract
BackgroundPlant non-specific lipid transfer proteins (nsLTPs), a group of small, basic ubiquitous proteins to participate in lipid transfer, cuticle formation and stress response, are involved in the regulation of plant growth and development. To date, although the nsLTP gene family of barley (Hordeum vulgare L.) has been preliminarily identified, it is still unclear in the recently completed genome database of barley and Qingke, and its transcriptional profiling under abiotic stress has not been elucidated as well.ResultsWe identified 40 barley nsLTP (HvLTP) genes through a strict screening strategy based on the latest barley genome and 35 Qingke nsLTP (HtLTP) orthologues using blastp, and these LTP genes were divided into four types (1, 2, D and G). At the same time, a comprehensive analysis of the physical and chemical characteristics, homology alignment, conserved motifs, gene structure and evolution of HvLTPs and HtLTPs further supported their similar nsLTP characteristics and classification. The genomic location of HvLTPs and HtLTPs showed that these genes were unevenly distributed, and obvious HvLTP and HtLTP gene clusters were found on the 7 chromosomes including six pairs of tandem repeats and one pair of segment repeats in the barley genome, indicating that these genes may be co-evolutionary and co-regulated. A spatial expression analysis showed that most HvLTPs and HtLTPs had different tissue-specific expression patterns. Moreover, the upstream cis-element analysis of HvLTPs and HtLTPs showed that there were many different stress-related transcriptional regulatory elements, and the expression pattern of HvLTPs and HtLTPs under abiotic stress also indicated that numerous HvLTP and HtLTP genes were related to the abiotic stress response. Taken together, these results may be due to the differences in promoters rather than by genes themselves resulting in different expression patterns under abiotic stress.ConclusionDue to a stringent screening and comprehensive analysis of the nsLTP gene family in barley and Qingke and its expression profile under abiotic stress, this study can be considered a useful source for the future studies of nsLTP genes in either barley or Qingke or for comparisons of different plant species.
Highlights
Plant non-specific lipid transfer proteins, a group of small, basic ubiquitous proteins to participate in lipid transfer, cuticle formation and stress response, are involved in the regulation of plant growth and development
Identification, sequence analysis and classification of HvLTPs and HtLTPs To identify the entire collection of putative nonredundant Plant non-specific lipid transfer proteins (nsLTP) genes in the barley genome, an accurate search workflow of nsLTP identification and data mining was performed (Fig. 1)
The 39 relevant barley nsLTP genes were downloaded by keyword searches from the NCBI, IPK and Phytozome databases
Summary
Plant non-specific lipid transfer proteins (nsLTPs), a group of small, basic ubiquitous proteins to participate in lipid transfer, cuticle formation and stress response, are involved in the regulation of plant growth and development. Plant lipid transfer protein (LTPs), named for their function that transfer phospholipids and fatty acids between cell membranes in vitro, and they are known as non-specific LTPs (nsLTPs) because of the characteristic of non-specific binding to different lipids [1, 2]. Plant nsLTPs are involved in multiple physiological functions, such as cuticular lipid transport, cutin synthesis, cell wall extension, pollen development, pollen tube growth and guidance, stigma and pollen adhesion, plant signalling, and seed maturation [1, 6,7,8]. Many studies have shown that nsLTP genes are closely related to abiotic stress resistance in plant [9, 12, 13, 19, 20]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
