Molecular characterization, expression and functional analysis of acyl-CoA-binding protein gene family in maize (Zea mays)

Background: Acyl-CoA-binding proteins (ACBPs) have a conserved acyl-CoA-binding (ACB) domain which facilitates binding to the acyl-CoA ester and trafficking in eukaryotic cells. Although the various functions of ACBP have been characterized in several plant species, its structural features, molecular evolution, expression profiling and function in Zea mays L . are still not clear. Results: Genome-wide analysis identified nine ZmACBP genes in Z. mays , which were divided into four groups (class I, class II, class III, and class IV) by a phylogenetic tree constructed with 48 ACBP genes from six plant species. The subcellular localizations of the ZmACBPs were displayed subcellular multi-localization via transient expression of green fluorescence protein (GFP) fusions in tobacco ( Nicotiana tabacum ) epidermal cells. The expression profiles of ZmACBPs are dramatically different in different organs and normal growth, as well as abiotic or biotic stress by Quantitative RT-PCR (qRT-PCR). Eight of nine ZmACBP genes located in metaQTL regions associated with agronomic traits in maize. The heterologous constitutive expression of ZmACBP1 and ZmACBP3 in Arabidopsis enhanced the resistance to salinity and osmotic stress. Conclusion: The ACBP genes family in Z. mays were highly conserved. ZmACBP genes had clear tissue and organ expression preference and were involved in abiotic or biotic stress response, suggesting their roles in plant growth and stress resistance.