Genome-wide identification of the ATP-dependent zinc metalloprotease (FtsH) in Triticeae species reveals that TaFtsH-1 regulates cadmium tolerance in Triticum aestivum

The ATP-dependent zinc metalloprotease (FtsH) protein gene family is essential for plant growth, development, and stress responses. Although FtsH genes have been identified in various plant species, the FtsH gene family in wheat (Triticum aestivum) remains unstudied. In this study, we identified 11 TaFtsH genes with uneven chromosomal distribution, significant variations in gene sequence length, and differing intron numbers among individual members. Additionally, these proteins exhibit similar physicochemical characteristics as well as secondary and tertiary structures. The FtsH genes can be classified into eight groups, each characterized by similar structures and conserved motifs. Intraspecific and interspecific comparisons further revealed extensive gene duplications within the TaFtsH gene family, indicating a closer relationship to maize. Analysis of cis-acting elements in the promoter regions of TaFtsH genes revealed developmental and stress-responsive elements in most of the genes. Expression pattern analysis showed that TaFtsH genes are expressed in all wheat tissues, though with varying patterns. TaFtsH genes displayed differential responses to CdCl2, ZnSO4, and MnSO4 stress treatments. Gene Ontology (GO) enrichment analysis indicated that TaFtsH genes are involved in protein hydrolysis. Barley stripe mosaic virus-induced gene silencing (BSMV-VIGS) technology confirmed the function of TaFtsH-1, indicating that silencing TaFtsH-1 enhances common wheat's resistance to cadmium (Cd) toxicity. In summary, this study offers an in-depth understanding of the FtsH gene family in wheat, establishing a solid basis for comprehending its functions, genetic mechanisms, and improving wheat's tolerance to heavy metal contamination.