The strained suspension was centrifuged again and the pellet used to produce mycelia and spherules. To grow mycelia, arthroconidia Selleck Etomoxir were washed 2 times with glucose-yeast extract (GYE) media and 2×106 spores/ml were incubated in 250 ml flat-bottom selleck compound Erlenmeyer flasks (Corning) in 50 ml GYE media. Four flasks were cultured in a 30°C incubator without shaking for 5 days. To grow spherules, arthroconidia were washed 2 times in modified Converse media [12]. The spores were inoculated at 4×106 arthroconidia/ml into a 250 ml baffled Erlenmeyer flask containing 50 ml of modified Converse media. Eight identical flasks were set up and grown on a shaker at 160 rpm, in 14% CO2 at 42°C. Four flasks were harvested

2 days after inoculation and the remaining four flasks after 8 days. The spherules did not rupture and release endospores within that time in this culture system. Inhibition of growth with nitisinone Nitisinone, 2-(2-nitro-4-trifluoromethylbenzoyl)-cyclohexane-1, 3 dione, a potent specific inhibitor

of 4-HPPD was purchased from Swedish Orphan Biovitrum, Sweden. A stock solution of 30 mg/ml was made in 0.2 M NaOH. Nitisinone was added at several concentrations to glucose yeast extract media (GYE) or modified converse media in the presence of 2×106 spores/ml in a 15 ml round-bottom tissue culture tubes (BD Falcon). The culture was grown as described above for mycelial and spherule growth. The control tubes contained equal amounts of 0.2 M NaOH without Nitisinone. For microscopy, 1% formaldehyde was added to the VDA chemical inhibitor culture overnight and the tubes were centrifuged 10,000 rpm for 10 min. The pellet was re-suspended in Lactophenol Aniline blue stain (Remel) and examined microscopically. RNA isolation C. immitis mycelia were harvested by straining the media from four cultures through a 40 μM nylon cell strainer (BD Falcon). The mycelia were picked up from the cell strainer using a sterile disposable loop (BD Falcon) and dropped in a 2 ml ZR BashingBead lysis tube with 0.5 mm beads (Zymoresearch) and 0.5 ml Qiazol reagent (Qiagen). The tubes were arranged in Florfenicol a pre-cooled Tissuelyzer II adapter (Qiagen) and mycelia was disrupted by shaking

at 50 Hz for 25 min. Spherules in Converse media were harvested from four 2 day cultures and four 8 day cultures. The cell concentration was determined by counting the spherules in Lactophenol Aniline blue stain. The media was centrifuged at 10,000 rpm for 10 min at 4°C. Qiazol (Qiagen) was added to the cell pellet at 4×106 spherules/ml and 0.5 ml of the mixture added to a 2 ml ZR BashingBead lysis tube with 0.5 mm beads (Zymoresearch). Total RNA was purified from mycelia and spherule samples (4 replicates/condition) using the RNeasy Microarray tissue mini-kit (Qiagen) in a Qiacube machine (Qiagen). If necessary RNA was concentrated or re-purified using RNeasy Minelute Cleanup kit (Qiagen) according to the manufacturer’s protocol.