Induction of Malathion resistance in CCE/CC128 cell line of Mediterranean fruit fly (Ceratitis capitata (Wied.)) (Diptera: Tephritidae)

A database of crop pest cell lines

We have developed an online database describing the known cell lines from Coleoptera, Diptera, Hemiptera, Hymenoptera, and Lepidoptera that were developed from agricultural pests. Cell line information has been primarily obtained from previous compilations of insect cell lines. We conducted in-depth Internet literature searches and drew on Internet sources such as the Cellosaurus database (https://web.expasy.org/cellosaurus/), and inventories from cell line depositories. Here, we report on a new database of insect cell lines, which covers 719 cell lines from 86 species. We have not included cell lines developed from Drosophila because they are already known from published databases, such as https://dgrc.bio.indiana.edu/cells/Catalog. We provide the designation, tissue and species of origin, cell line developer, unique characteristics, its use in various applications, publications, and patents, and, when known, insect virus susceptibility. This information has been assembled and organized into a searchable database available at the link https://entomology.ca.uky.edu/aginsectcellsdatabase which will be updated on an ongoing basis.

Establishment and characterization of the Bactrocera dorsalis (Diptera: Tephritidae) embryonic cell line QAU-Bd-E-2

In this study, we successfully established a Bactrocera dorsalis (Diptera: Tephritidae) embryonic cell line, i.e., QAU-Bd-E-2, from the insect eggs. The cells have been stably passaged for more than 60 times in TNM-FH medium with 10% fetal bovine serum (FBS). QAU-Bd-E-2 cells are adherent cells. Most of the cells were round, spindle-shaped, and rod-shaped. Round cells accounted for 82.3%, with a diameter of 13.9 ± 2.6 µm; spindle-shaped cells accounted for 9.8%, with the size of 51.2 ± 11.2 µm × 10.3 ± 3.1 µm; the rod-shaped cells accounted for 7.9%, with the size of 35.2 ± 9.4 µm × 12.0 ± 2.5 µm. The mitochondrial cytochrome oxidase I subunit (CoI) gene from QAU-Bd-E-2 cells was amplified, and the 657 bp fragment had a 100% similarity with the CoI gene of B. dorsalis, suggesting that the cell line was derived from B. dorsalis. The chromosome number of QAU-Bd-E-2 cells was mostly 12, which is the same as the B. dorsalis chromosome number. The cell density of QAU-Bd-E-2 cells reached the maximum (3.4 × 10⁶ cells/mL) at 192 h, and the population doubling time was 31.9 h. Bactrocera dorsalis cripavirus (BdCV) could replicate in QAU-Bd-E-2 cells, suggesting that this cell line could be used for in-depth study of the relationship between virus and host.

Effects of lipopolysaccharide and juvenile hormone III treatments on cell growth and gene expression in the Ceratitis capitata (Diptera: Tephritidae) CCE/CC128 cell line

The Mediterranean fruit fly Ceratitis capitata is one of the most important insect pest species in the world. It has a high colonization capacity and population variety, giving it considerable genetic diversity. Strategies for its control have included the sterile insect technique and insect growth regulators. Many studies have analyzed the medfly transcriptome, and along with the medfly genome sequence, the sequences of multiple genes related to sex determination, mating, development, pheromone detection, immunity, or stress have been identified. In this study, the medfly CCE/CC128 cell line was used to assess cell growth variation and changes in the expression of genes covering different functions, after lipopolysaccharide (LPS) and juvenile hormone III (JHIII) treatments. No significant effects on cell growth and gene expression were observed in the cells treated with LPS. In the cells treated with JHIII, the results showed significant effects on cell growth, and an overexpression was found of the Shade gene, one of the Halloween gene members of the cytochrome p450 family, which is involved in development and the synthesis of 20-hydroxyecdysone. This study shows preliminary results on the insect cell line in combination with whole-genome sequencing, which can facilitate studies regarding growth, toxicity, immunity, and transcriptome regulations as a response to different compounds and environmental alterations.

Putative-farnesoic acid O-methyltransferase (FAMeT) in medfly reproduction

A gene potentially involved in juvenile hormone (JH) biosynthesis was previously identified in Ceratitis capitata as the putative-farnesoic acid O-methyltransferase (FAMeT). Since JH is involved in insect reproduction, we silenced the putative-FAMeT expression by RNA interference in Ceratitis capitata to evaluate its implication in egg production. FAMeT gene expression was knocked down in females and males after eclosion and in 1- and 2-day-old females. Treated specimens were left to mate with each other or with untreated partners to evaluate the extent of each sex influencing egg production. Gene silencing was investigated by Real-Time PCR. Results unambiguously showed that FAMeT has a measurable role on the fertility of both medfly sexes.