RESUMO
The olfactory system plays a key role in regulating insect behaviors, such as locating host plants, spawning sites, and mating partners and avoiding predators. Chemosensory genes are required for olfactory recognition in insects. Curculio dieckmanni Faust. (Coleoptera: Curculionidae) damages hazelnuts and causes severe economic losses. There are no effective control measures, but understanding the olfaction mechanisms of this insect could lead to a new approach for population management. However, the genes that perform chemosensory functions in C. dieckmanni are still unclear. Using high-throughput sequencing, we assembled the antennal transcriptome of C. dieckmanni and annotated the major chemosensory gene families. Of the chemosensory gene families, we found 23 odorant-binding proteins, 15 chemosensory proteins, 2 sensory neuron membrane proteins, 15 odorant receptors, 23 ionotropic receptors, and nine gustatory receptors. Using Blast sequence alignment and phylogenetic analysis, the sequences of these proteins were identified. Male- and female-specific chemosensory genes involved in odorant detection and recognition were validated by qRT-PCR. Among the chemosensory genes, we found significant differences in the expression of CdieOBP8, CdieOBP9, CdieOBP19, CdieOBP20, CdieOBP21, CdieCSP15, CdieOR13, and CdieOR15 between adult male and female C. dieckmanni. A total of 87 expressed chemosensory proteins were found in C. dieckmanni. Investigating these proteins will help reveal the molecular mechanism of odorant recognition in C. dieckmanni and may aid the development of novel control strategies for this species.
RESUMO
BACKGROUND: The aim of this study was to pilot a method of a small-scale survey for the assessment of Keshan disease (KD) elimination at township level. METHODS: The prevalence of chronic KD was obtained by case-searching the whole population. The endemic village with the highest prevalence of chronic KD was selected as the key village for the survey of latent KD prevalence rate among permanent residents. The selenium levels in the head hair of individuals in the key village was measured. The professionals of the department of endemic disease control, the township and village doctors were surveyed by pre-designed questionnaire survey for KD interventions. RESULTS: We conducted this study in 2013. Yuanbao township had a population of 16 487 people and 14 862 permanent residents. There were no acute or subacute KD cases in the previous 5 years. The prevalence rate of chronic KD and natural chronic KD were 6.7/10 000 and 3.4/10 000 respectively. The prevalence rate of latent KD was 250.6/10 000, higher than the elimination criterion. The head hair selenium levels were 0.23±0.18 mg/kg. CONCLUSIONS: The small-scale survey methodology for assessing KD elimination at township level was feasible. KD among the people living in Yuanbao township has not been eliminated.
