Control of morphology and virulence by ADP-ribosylation factors (Arf) in Mucor circinelloides
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Mucor circinelloides is a dimorphic fungus used to study cell differentiation that has emerged as a model to characterize mucormycosis. In this work, we identified four ADP-ribosylation factor (Arf)-encoding genes (arf1–arf4) and study their role in the morphogenesis and virulence. Arfs are key regulators of the vesicular trafficking process and are associated with both growth and virulence in fungi. Arf1 and Arf2 share 96% identity and Arf3 and Arf4 share 89% identity, which suggests that the genes arose through gene-duplication events in M. circinelloides. Transcription analysis revealed that certain arf genes are affected by dimorphism of M. circinelloides, such as the arf2 transcript, which was accumulated during yeast development. Therefore, we created knockout mutants of four arf genes to evaluate their function in dimorphism and virulence. We found that both arf1 and arf2 are required for sporulation, but these genes also perform distinct functions; arf2 participates in yeast development, whereas arf1 is involved in aerobic growth. Conversely, arf3 and arf4 play only minor roles during aerobic growth. Moreover, we observed that all single arf-mutant strains are more virulent than the wild-type strain in mouse and nematode models, with the arf3 mutant being most virulent. Lastly, arf1/arf2 and arf3/arf4 double mutations produced heterokaryon strains that did not reach the homokaryotic state, indicating that these genes participate in essential and redundant functions. Overall, this work reveals that Arfs proteins regulate important cellular processes in M. circinelloides such as morphogenesis and virulence, laying the foundation to characterize the molecular networks underlying this regulation.
KeywordsADP-ribosylation factor Arf protein Fungal virulence Mucor Secretion Vesicle trafficking
This work was supported by grants from Coordinación de la Investigación Científica, UMSNH, México (2.6, 2.35), Consejo Nacional de Ciencia y Tecnología, México (CONACYT; 181747, 167071, and 256119), and Fundación Séneca-Agencia de Ciencia y Tecnología de la Región de Murcia, Spain (19339/PI/14). JA P-M, G M-H, MI V-M, and NY R-M were supported by postgraduate fellowships from CONACYT and CP-A by Ministerio de Educación, Cultura y Deporte of Spain (FPU-14/01832).
JAP-M, GM-H, MIV-M, CP-A, VA-C, NYR-M, RO-A, data acquisition and interpretation; RO-A, IEJ-G, JC-G, MIR-D, VG, reagents, critical analysis, and revision of the article for intellectual content; MIR-D, VG, VM-C, conception and design of the work and data analysis and interpretation; VM-C, drafting of the article.
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Conflict of interest
All authors declared that they have no potential conflict of interest.
Research involving human/animal participants
This article does not contain any studies with human participants.
- Colicelli J (2004) Human RAS superfamily proteins and related GTPases. Sci STKE 2004, RE13Google Scholar
- Punt PJ, Seiboth B, Weenink XO, van Zeijl C, Lenders M, Konetschny C, Ram AF, Montijn R, Kubicek CP, van den Hondel CAMJJ (2001) Identification and characterization of a family of secretion-related small GTPase-encoding genes from the filamentous fungus Aspergillus niger: a putative SEC4 homologue is not essential for growth. Mol Microbiol 41:513–525CrossRefPubMedGoogle Scholar
- Rodríguez-Andrade E, Hernández-Ramírez KC, Díaz-Peréz SP, Díaz-Magaña A, Chávez-Moctezuma MP, Meza-Carmen V, Ortíz-Alvarado R, Cervantes C, Ramírez-Díaz MI (2016) Genes from pUM505 plasmid contribute to Pseudomonas aeruginosa virulence. Antonie Van Leeuwenhoek 109:389–396CrossRefPubMedGoogle Scholar
- Sambrook J, Russell RW (2001) Molecular cloning: A laboratory manual, 3rd edn. Cold spring harbor laboratory press, Cold Spring HarborGoogle Scholar
- SecretaríadeAgricultura, G, Desarrollo Rural, Pesca y Alimentación (SAGARPA) (2001) NORMA Oficial Mexicana NOM-062-ZOO-1999. Especificaciones técnicas para la producción, cuidado y uso de los animales de laboratorio. Diario Oficial de la Federación 2:107–167 (In Spanish) Google Scholar
- Stiernagle T (2006) Maintenance of C. elegans. WormBook. edn. The C. elegans Research CommunityGoogle Scholar
- Trieu TA, Navarro-Mendoza MI, Pérez-Arques C, Sanchis M, Capilla J, Navarro-Rodriguez P, Lopez-Fernandez L, Torres-Martínez S, Garre V, Ruiz-Vázquez RM, Nicolás FE (2017) RNAi-Based Functional Genomics Identifies New Virulence Determinants in Mucormycosis. PLoS Pathog 13:e1006150CrossRefPubMedPubMedCentralGoogle Scholar
- Valle-Maldonado MI, Jácome-Galarza IE, Díaz-Pérez AL, Martínez-Cadena G, Campos-García J, Ramírez-Díaz MI, Reyes-De la Cruz H, Riveros-Rosas H, Díaz-Pérez C, Meza-Carmen V (2015a) Phylogenetic analysis of fungal heterotrimeric G protein-encoding genes and their expression during dimorphism in Mucor circinelloides. Fungal Biol 119:1179–1193CrossRefPubMedGoogle Scholar