Immunodetection of Truncated Forms of the α6 Subunit of the nAChR in the Brain of Spinosad Resistant Phenotypes.

The α6 subunit of the nicotinic acetylcholine receptor (nAChR) has been proposed as the target for spinosad in insects. Point mutations that result in premature stop codons in the gene of flies have been previously associated with spinosad resistance, but it is unknown if these transcripts are translated and if so, what is the location of the putative truncated proteins. In this work, we produced a specific antibody against α6 (Ccα6) and validated it by ELISA, Western blotting and immunofluorescence assays in brain tissues.

Current situation and forecasting of resistance evolution to lambda-cyhalothrin in Spanish medfly populations.

Background: The control of the Mediterranean fruit fly Ceratitis capitata (Wiedemann) in Spanish field populations mainly relies on the insecticides lambda-cyhalothrin and spinosad as bait sprays. However, their sustainable used is compromised by the development of lambda-cyhalothrin resistance and the detection of spinosad resistant alleles. In addition, the use of lure-and-kill traps covered with deltamethrin has increased in the last years.

Inheritance, Fitness Cost, and Management of Lambda-Cyhalothrin Resistance in a Laboratory-Selected Strain of (Wiedemann).

The management of the medfly, , in Spanish citrus crops relies mainly on the use of insecticides and the release of sterile males. However, the development of resistance to different insecticides in field populations, including lambda-cyhalothrin, implies a threat for the sustainable control of this pest. The inheritance, fitness cost, and management of lambda-cyhalothrin resistance were examined in the laboratory-selected W-1Kλ strain.

Field detection and predicted evolution of spinosad resistance in Ceratitis capitata.

Background: The sustainable control of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), is compromised by the development of resistance to malathion and lambda-cyhalothrin in Spanish field populations. At present, field populations remain susceptible to spinosad. However, the resistant strain JW-100s has been obtained under laboratory selection with spinosad, and resistance has been associated with the presence of different mutations causing truncated transcripts of the α6 subunit of the nicotinic acetylcholine receptor (nAChRα6).

Multiple mutations in the nicotinic acetylcholine receptor Ccα6 gene associated with resistance to spinosad in medfly.

Spinosad is an insecticide widely used for the control of insect pest species, including Mediterranean fruit fly, Ceratitis capitata. Its target site is the α6 subunit of the nicotinic acetylcholine receptors, and different mutations in this subunit confer resistance to spinosad in diverse insect species. The insect α6 gene contains 12 exons, with mutually exclusive versions of exons 3 (3a, 3b) and 8 (8a, 8b, 8c).

Real-Time RT-PCR assay to quantify the expression of fum1 and fum19 genes from the Fumonisin-producing Fusarium verticillioides.

Fumonisins are a group of mycotoxins produced by Fusarium species of the Gibberella fujikuroi species complex that contaminate food and feed products, and represent a risk for human and animal health. In this work, we have developed a specific real-time reverse transcription-PCR (RT-PCR) assay to quantify the level of expression of two genes of the fumonisin biosynthetic cluster in F. verticillioides: fum1 (that encodes a polyketide synthase enzyme) and the ABC transporter encoding gene fum19.

A novel MFS transporter encoding gene in Fusarium verticillioides probably involved in iron-siderophore transport.

The major facilitator superfamily (MFS) is a ubiquitous group of proteins involved in the transport of a wide range of compounds, including toxins produced by fungal species. In this paper, a novel MFS encoding gene (Fusarium iron related gene or FIR1), which had shown an up-regulation in fumonisin-inducing conditions, has been identified and characterized. The deduced protein sequence, which predicted 14 transmembrane domains typical of MFS transporters and its phylogenetic relationships with representative members of MFS transporters suggested a possible function of FIR1 as a siderophore transporter.