Comparative de novo transcriptome profiles in Asparagus officinalis and A. kiusianus during the early stage of Phomopsis asparagi infection.

Asparagus kiusianus, an important wild relative of cultivated asparagus (A. officinalis), exhibits resistance to stem blight disease caused by Phomopsis asparagi. However, the mechanisms underlying this resistance are not understood and no transcriptomic or genetic resources are available for this species. De novo transcriptome sequencing of A. officinalis and A. kiusianus stems was performed 24 h after inoculation with P. asparagi. In total, 35,259 and 36,321 transcripts were annotated in A. officinalis and A. kiusianus, respectively. 1,027 up-regulated and 752 down-regulated transcripts were differentially expressed in the two Asparagus species. RNA sequencing data were validated using quantitative real-time reverse transcription PCR. Several defense-related genes including peroxidase 4, cationic peroxidase SPC4-like, pathogenesis-related protein-1-like, and jasmonic acid biosynthesis and signaling-related genes including phospholipase D alpha 1, 12-oxophytodienoate reductase and jasmonate-induced protein 23 KD were up-regulated in A. kiusianus relative to A. officinalis. In addition, infected A. kiusianuns exhibited a substantial increase in jasmonic acid and methyl jasmonate relative to A. officinalis. Peroxidase activity was significantly elevated in infected A. kiusianus compared with infected A. officinalis. Our transcriptomic database provides a resource for identifying novel genes and molecular markers-associated with Phomopsis disease resistance and will facilitate breeding and improvement of cultivated asparagus varieties.

Invasive Myceliophthora thermophila infection mimicking invasive aspergillosis in a neutropenic patient: a new cause of cross-reactivity with the Aspergillus galactomannan serum antigen assay.

Myceliophthora thermophila is a thermophilic mould widely found in the environment but rarely responsible for human infections. We describe a case of invasive Myceliophthora thermophila infection mimicking invasive aspergillosis in a neutropenic patient with haematological malignancy. Cross-reactivity with Aspergillus galactomannan assay (GM) was demonstrated by repeated positive results and confirmed by cross-reaction between the fungal isolate and the GM assay. The patient was successfully treated with voriconazole. Potential GM cross-reactivity must be considered in future studies including patients categorized as having probable invasive aspergillosis using the GM as the only mycological criterion.