Genome-wide investigation and transcriptional profiling of the oxidosqualene cyclase (OSC) genes in wheat (Triticum aestivum L.)

Triterpene scaffolds are cyclized by differential functional genes of the oxidosqualene cyclase (OSC) gene family, which are widely present in plant species. Thirty-nine OSCs genes were identified from the hexaploid bread wheat (Triticum aestivum L.) genome. The gene structure organization and the distribution of conserved motifs of OSCs gene family revealed that the TaOSC proteins are highly conserved. By phylogenetic analysis, all OSC proteins from wheat and other cereal crops were clustered into eleven subfamilies (Ⅰ-Ⅺ). Based on the publicly available transcriptional profiling, the tissue-specific expression patterns of TaOSC during several developmental stages revealed diverged expression patterns, indicating that the TaOSC family has undergone subfunctionalization. Furthermore, homeolog expression bias was commonly detected in the TaOSC subfamilies, such as the expression of Ta5A004900 and Ta5D011800 in the subfamily Ⅱ were specifically expressed in the leaf sheath and flag leaf s...