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Abstract Understanding the development process of male and female mosquitoes provides important basic information for sterile insect release programmes and is important for improving other vector control strategies. However, little is known about the molecular mechanisms that distinguish male from female‐specific developmental processes in this species. We used IlluminaRNA‐seq to identify sex‐specific genes during pupal and adult stages. One hundred and forty‐seven genes were expressed only in pupal males, 56 genes were expressed in adult males and another 82 genes were commonly expressed in both male samples. In addition, 26 genes were expressed only in the pupal females, 163 genes were found in the adult females and only one gene was expressed in both female samples. A further quantitative real‐time PCR validation of selected genes from the RNA sequencing (RNA‐seq) analysis confirmed upregulation of those genes in a sex‐specific manner, including: fibrinogen and fibronectin, a zinc finger protein, phospholipase A(2) and a serine protein for female pupae; venom allergen 3, a perlecan, testis‐specific serine/threonine‐protein kinase 1, testis‐specific serine/threonine‐protein kinase 6 and cytochrome c‐2 for male pupae; a salivary protein, D7 protein precursor, trypsin 7 precursor, D7 protein and nanos for female adults; and tetraspanin F139, cytosol aminopeptidase, testis‐specific serine/threonine‐protein kinase 1, a testis‐specific serine/threonine‐protein kinase 6 and a C‐type lectin for male adults. These findings provide insight into the development and physiology ofCulexmosquitoes, which will help in the development of more effective control methods for these disease vectors.
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Discovery of Novel Effector Protein Candidates Produced in the Dorsal Gland of Root-Knot Nematode Adult Females
Root-knot nematodes (RKN; Meloidogyne spp.) represent one of the most damaging groups of plant-parasitic nematodes. They secrete effector proteins through a protrusible stylet to manipulate host cells for their benefit. Stylet-secreted effector proteins are produced within specialized secretory esophageal gland cells, one dorsal (DG) and two subventral (SvG), whose activity differ throughout the nematode life cycle. Previous gland transcriptomic profiling studies identified dozens of candidate RKN effectors, but were focused on the juvenile stages of the nematode when the SvGs are most active. We developed a new approach to enrich for the active DGs of RKN M. incognita adult females for RNA and protein extraction. Female heads were manually cut from the body, and a combination of sonication/vortexing was used to dislodge contents inside the heads. DG-enriched fractions were collected by filtering using cell strainers. Comparative transcriptome profiling of pre-parasitic second-stage juveniles, female heads, and DG-enriched samples was conducted using RNA sequencing. Application of an established effector mining pipeline led to the identification of 83 candidate effector genes upregulated in DG-enriched samples of adult females that code for proteins with a predicted signal peptide, but lack transmembrane domains or homology to proteins in the free-living nematode Caenorhabditis elegans. In situ hybridization resulted in the identification of 14 new DG-specific candidate effectors expressed in adult females. Taken together, we have identified novel candidate Meloidogyne effector genes that may have essential roles during later stages of parasitism.
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- Award ID(s):
- 1933525
- PAR ID:
- 10435327
- Date Published:
- Journal Name:
- Molecular Plant-Microbe Interactions®
- ISSN:
- 0894-0282
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1094/MPMI-11-22-0232-R
