Genome-Wide Identification and Expression Pattern Analysis of TIFY Family Genes Reveal Their Potential Roles in Phalaenopsis aphrodite Flower Opening

The TIFY gene family (formerly known as the zinc finger proteins expressed in inflorescence meristem (ZIM) family) not only functions in plant defense responses but also are widely involved in regulating plant growth and development. However, the identification and functional analysis of TIFY proteins remain unexplored in Orchidaceae. Here, we identified 19 putative genes in the genome. The phylogenetic tree classified them into four subfamilies: 14 members from JAZ, 3 members from ZML, and 1 each from PPD and TIFY. Sequence analysis revealed that all TIFY proteins contained a TIFY domain. Exon-intron analysis showed that the intron number and length of genes varied, whereas the same subfamily and subgroup genes had similar exon or intron numbers and distributions. The most abundant -elements in the promoter regions of the 19 genes were associated with light responsiveness, followed by MeJA and ABA, indicating their potential regulation by light and phytohormones. The 13 candidate genes screened from the transcriptome data exhibited two types of expression trends, suggesting their different roles in cell proliferation and cell expansion of floral organ growth during flower opening. Overall, this study serves as a background for investigating the underlying roles of genes in floral organ growth in .