title: Phylogenic analysis of adhesion related genes Mad1 revealed a positive selection for the evolution of trapping devices of nematode-trapping fungi.
abstract: Adhesions, the major components of the extracellular fibrillar polymers which accumulate on the outer surface of adhesive traps of nematode-trapping fungi, are thought to have played important roles during the evolution of trapping devices. Phylogenetic analyses based on the genes related to adhesive materials can be of great importance for understanding the evolution of trapping devices. Recently, AoMad1, one homologous gene of the entomopathogenic fungus Metarhizium anisopliae cell wall protein MAD1, has been functionally characterized as involved in the production of adhesions in the nematode-trapping fungus Arthrobotrys oligospora. In this study, we cloned Mad1 homologous genes from nematode-trapping fungi with various trapping devices. Phylogenetic analyses suggested that species which formed nonadhesive constricting ring (CR) traps more basally placed and species with adhesive traps evolved along two lineages. Likelihood ratio tests (LRT) revealed that significant positive selective pressure likely acted on the ancestral trapping devices including both adhesive and mechanical traps, indicating that the Mad1 genes likely played important roles during the evolution of nematode-trapping fungi. Our study provides new insights into the evolution of trapping devices of nematode-trapping fungi and also contributes to understanding the importance of adhesions during the evolution of nematode-trapping fungi.
authors.affiliation: Laboratory for Conservation and Utilization of Bio-resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, 650091, P.R. China.
authors.forename: Juan
authors.initials: J
authors.lastname: Li
authors.affiliation: Laboratory for Conservation and Utilization of Bio-resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, 650091, P.R. China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Laboratory for Conservation and Utilization of Bio-resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, 650091, P.R. China.
authors.forename: Hongyan
authors.initials: H
authors.lastname: Zhu
authors.affiliation: Laboratory for Conservation and Utilization of Bio-resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, 650091, P.R. China.
authors.forename: Ke-Qin
authors.initials: KQ
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001203:Ascomycota / Q000235:genetics*; D005075:Biological Evolution; D002448:Cell Adhesion / Q000235:genetics; D018797:Cell Cycle Proteins / Q000235:genetics*; D002473:Cell Wall / Q000378:metabolism*; D005109:Extracellular Matrix / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D009348:Nematoda / Q000502:physiology; D010802:Phylogeny
chemical_list: D018797:Cell Cycle Proteins; D005656:Fungal Proteins