L-arginine is essential for conidiation in the filamentous fungus Coniothyrium minitans

Fungal Genet Biol. 2007 Dec;44(12):1368-79. doi: 10.1016/j.fgb.2007.07.007. Epub 2007 Aug 6.

Abstract

Conidiation is important in the life cycles of mitosporic fungi for survival and transmission. A full-length cDNA of one gene named CMCPS1 encoding L-arginine-specific carbamoyl-phosphate synthase was obtained from Coniothyrium minitans, a sclerotial parasite of the plant pathogenic fungus Sclerotinia sclerotiorum. T-DNA insertional disruption of CMCPS1 resulted in conidiation deficiency of mutant ZS-1T2029, and this was confirmed with the RNAi technique. The phenotype was restored by complementation with L-arginine, and the effect of L-arginine on conidiation may be mediated by nitric oxide, which is catalyzed by nitric oxide synthase (NOS). Conidiation of ZS-1T2029 was restored by sodium nitroprussiate, a NO donor; and conidiation of wild type strain ZS-1 could be suppressed by L-NAME, an inhibitor of NOS. The highest amount of NO in mycelia was detected at an early stage of conidiation (72 hpi) in liquid shake culture medium. Staining with the NO-sensitive fluorescent probe, DAF-FM DA, gave strong fluorescent signals in primordia and young pycnidia. This work presents the first report that L-arginine is involved in conidiation of C. minitans, and the possibility of L-arginine-derived nitric oxide-mediated conidiation among fungi and possible modes of action are discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arginine / metabolism*
  • Arginine / pharmacology
  • Ascomycota / genetics
  • Ascomycota / metabolism*
  • Ascomycota / physiology
  • Blotting, Southern
  • Carbon-Nitrogen Ligases with Glutamine as Amide-N-Donor / genetics
  • Carbon-Nitrogen Ligases with Glutamine as Amide-N-Donor / metabolism
  • Citrulline / pharmacology
  • DNA, Bacterial / genetics
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism
  • NG-Nitroarginine Methyl Ester / pharmacology
  • Nitric Oxide Donors / pharmacology
  • Nitric Oxide Synthase / antagonists & inhibitors
  • Nitric Oxide Synthase / metabolism
  • Nitroprusside / pharmacology
  • RNA Interference
  • Signal Transduction / drug effects
  • Signal Transduction / genetics
  • Signal Transduction / physiology
  • Spores, Fungal / drug effects
  • Spores, Fungal / genetics
  • Spores, Fungal / growth & development*

Substances

  • DNA, Bacterial
  • Fungal Proteins
  • Nitric Oxide Donors
  • T-DNA
  • Nitroprusside
  • Citrulline
  • Arginine
  • Nitric Oxide Synthase
  • Carbon-Nitrogen Ligases with Glutamine as Amide-N-Donor
  • carbamoyl phosphate synthetase (arginine-specific)
  • NG-Nitroarginine Methyl Ester