The L-type Ca2+ Channel Blocker Nifedipine Inhibits Mycelial Growth, Sporulation, and Virulence of Phytophthora capsici

Abstract

The oomycete vegetable pathogen Phytophthora capsici causes significant losses of important vegetable crops worldwide. Calcium and other plant nutrients have been used in disease management of oomycete pathogens. Calcium homeostasis and signaling is essential for numerous biological processes, and Ca2+ channel blockers prevent excessive Ca2+ influx into the fungal cell. However, it is not known whether voltage-gated Ca2+ channel blockers improve control over oomycete pathogens. In the present study, we compared the inhibitory effects of CaCl2 and the extracellular Ca2+ chelator EDTA on mycelial growth and found that calcium assimilation plays a key role in P. capsici mycelial growth. Next, we involved the voltage-gated Ca2+ channel blockers verapamil (VP) and nifedipine (NFD) to analyze the effect of Ca2+ channel blockers on mycelial growth and sporulation; the results suggested that NFD, but not VP, caused significant inhibition. Ion rescue in an NFD-induced inhibition assay suggested that NFD-induced inhibition is calcium-dependent. In addition, NFD increased P. capsici sensitivity to H2O2 in a calcium-dependent manner, and extracellular calcium rescued it. Furthermore, NFD inhibited the virulence and gene expression related to its pathogenicity. These results suggest that NFD inhibits mycelial growth, sporulation, and virulence of P. capsici.

Comparative analysis of Phytophthora genomes reveals oomycete pathogenesis in crops

“…We analysed P. fragariae , P. rubi and five additional available Phytophthora genomes, including P. infestans T30-4 ( Haas et al., 2009 ), P. parasitica INRA-310 ( Blackman et al., 2014 ), P. sojae V3.0 ( Tyler et al., 2006 ), P. nicotianae ( Liu et al., 2016a , b ) and P. ramorum ( Tyler et al., 2006 ). The observed size variation among these Phytophthora genomes can be attributed to their repeat content, length of the intergenic regions, and number of pseudogenes ( Table 1 and Note S1).…”

“…WGD events have been detected in P. infestans , P. sojae , P. ramorum, P. nicotianae and P. parasitica genomes ( Tyler et al., 2006 ; Haas et al., 2009 ; Blackman et al., 2014 ; Liu et al., 2016a , b ). In addition, large intraspecies synteny was detected and many short homologous segments were localised on the same scaffold in P. infestans , P. sojae and P. ramorum ( van Hooff et al., 2014 ).…”

“…The voltage-gated potassium channels of most Phytophthora species are species-specific. In P. nicotianae , the specific voltage-gated calcium channel may regulate the migration of zoosporogenesis, sporulation and mycelial growth ( Liu et al., 2016a , b ). G-protein-coupled receptor signalling in P. sojae and P. infestans are the same but are specific to gene structure, indicating that there may be different pathogenic mechanisms.…”

Polycystic Kidney Disease Ryanodine Receptor Domain (PKDRR) Proteins in Oomycetes

“…Knockdown to the heterotrimeric G-protein α-subunit in Phytophthora sojae decreases chemotaxis of zoospores towards the plant isoflavone daidzein, indicating a role for the phospholipase C-IP 3 -ITPR-Ca 2+ -signalling pathway in this process [ 14 ]. The L-type voltage-gated Ca 2+ channel antagonist nifedipine is reported to inhibit the mycelial growth and sporulation of P. capsici [ 15 ].…”

Genome-wide characterization deciphers distinct properties of major intrinsic proteins in six Phytophthora species

“…P. ramorum , the cause of death of oak trees in North America, has severe impact on natural ecosystem, and P. cinnamomi is a substantial threat to natural eucalyptus forests in Australia (Tyler et al, 2006; Lamour et al, 2012; Thines, 2014). P. capsici causes foot rot disease in black pepper and Phytophthora blight in vegetable crops, which causes serious effects on the production of cucurbits, peppers, eggplants, and numerous other important vegetables worldwide (Jackson et al, 2012; Hao et al, 2016; Johnson et al, 2016; Liu et al, 2016). P. parasitica infects a broad range of plants, being capable of infecting over 72 plant genera worldwide (Blackman et al, 2015; Meng et al, 2015).…”