Genome-Wide Analysis of the PLATZ Gene Family and Identification of Seed Development-Related Genes in Flax [ Linum usitatissimum L.]

The plant AT-rich sequence and zinc-binding proteins (PLATZ) are a new class of zinc-dependent DNA-binding proteins that play important roles in plant growth and development. But it has not been systematically identified in flax (Linum usitatissimum L.), as an important seed crop with high nutritional value. In this study, 28 LuPLATZ proteins were identified from flax and divided into six phylogenetic groups. Fragment duplication was an important driving factor in the evolution of LuPLATZ genes. The RNA-seq results showed that the LuPLATZ genes had different expression patterns. Quantitative analysis of 16 LuPLATZ genes was performed, and the qRT-PCR results were consistent with the RNA-seq results. The expression of LuPLATZ6, LuPLATZ23, and LuPLATZ27 increased significantly during seed development. The observed change in the expression pattern suggests that these three genes could have significant regulatory functions during seed formation. These three LuPLATZ proteins were localized to the nucleus, suggesting that they could be conventional transcription factors. LuPLATZ23 and LuPLATZ27 were co-expressed with LuNAC1 and LuNAC75, suggesting an interactive relationship. This study aims to offer a theoretical foundation for high-yielding molecular breeding of flax.