Phylogenetic analysis of MrUBI4 and the polyubiquitin orthologs from various fungi, plants, and animals. (A) The phylogenetic tree was generated via the MEGA7 software using default settings (neighbor-joining method). The amino acid sequences of polyubiquitin that were used in this analysis are as follows: Magnaporthe oryzae (EHA54394.1), Metarhizium robertsii (MAA_02160), Trichoderma parareesei (OTA03154.1), Fusarium oxysporum (ENH62031.1), Candida albicans (CAA90901.1), Arabidopsis thaliana (CAB81074.1), Saccharomyces cerevisiae (YLL039C), Schizosaccharomyces pombe (SPBC337.08c), Zea mays (NP_001316595.1), Caenorhabditis elegans (F25B5.4/WBGene00006727), Mus musculus (MGI:98888), and Homo sapiens (ENSG00000170315). (B) The variant number of monomeric ubiquitin repeats in the polyubiquitin protein of different species. Box with Ub in blue represents 1 monomeric ubiquitin repeat.