Fusarium oxysporum Casein Kinase 1, a Negative Regulator of the Plasma Membrane H+-ATPase Pma1, Is Required for Development and Pathogenicity

Melani Mariscal; Cristina Miguel-Rojas; Concepción Hera; Tânia R Fernandes; Antonio Di Pietro

doi:10.3390/jof8121300

Fusarium oxysporum Casein Kinase 1, a Negative Regulator of the Plasma Membrane H⁺-ATPase Pma1, Is Required for Development and Pathogenicity

J Fungi (Basel). 2022 Dec 15;8(12):1300. doi: 10.3390/jof8121300.

Authors

Melani Mariscal¹, Cristina Miguel-Rojas¹, Concepción Hera¹, Tânia R Fernandes¹, Antonio Di Pietro¹

Affiliation

¹ Departamento de Genética, Campus de Excelencia Internacional Agroalimentario ceiA3, Universidad de Córdoba, 14014 Cordoba, Spain.

Abstract

Like many hemibiotrophic plant pathogens, the root-infecting vascular wilt fungus Fusarium oxysporum induces an increase in the pH of the surrounding host tissue. How alkalinization promotes fungal infection is not fully understood, but recent studies point towards the role of cytosolic pH (pH_c) and mitogen-activated protein kinase (MAPK) signaling. In fungi, pH_c is mainly controlled by the essential plasma membrane H⁺-ATPase Pma1. Here we created mutants of F. oxysporum lacking casein kinase 1 (Ck1), a known negative regulator of Pma1. We found that the ck1Δ mutants have constitutively high Pma1 activity and exhibit reduced alkalinization of the surrounding medium as well as decreased hyphal growth and conidiation. Importantly, the ck1Δ mutants exhibit defects in hyphal chemotropism towards plant roots and in pathogenicity on tomato plants. Thus, Ck1 is a key regulator of the development and virulence of F. oxysporum.

Keywords: Fusarium oxysporum; H+-ATPase; casein kinase 1; filamentous fungus; pH; virulence.

Grants and funding

This work was supported by grants from the Spanish Ministry of Science and Innovation (MICINN, grant PID2019-108045RB-I00) and Junta de Andalucía (P20_00179) to A.D.P.; M.M. was supported by PhD fellowship BES-2017-082775 from MICINN. C.M.-R. was supported by PhD fellowship FPU from the Spanish Ministry of Education and Science (MEC). T.R.F. was supported by the Marie Curie ITN FUNGIBRAIN (FP7-PEOPLE-ITN-607963).