The habitat of Drosophila melanogaster is the environment of fruit decay/fermentation which emits high concentrations of chemicals. Our recent studies revealed that D. melanogaster has been evolutionarily adapted to its habitat through tolerance to chemicals and induction of antimicrobial peptides (AMPs) plays an important role for chemical tolerance. To determine the correlation between AMPs and the chemical tolerance pathway, we hypothesized that expression of AMPs is induced by tissue damages or ROS caused by chemical exposure and AMPs activate antioxidant enzymes, thereby inducing chemical tolerance in D. melanogaster. Therefore, in this study, we investigated the induction levels of genes associated with necrosis (EGR and BSK), apoptosis (Dronc, Dcp1, and Drice), antioxidant physiology (SOD1, SOD2, CAT, Trxr1, GstD2, and GstD5), and SAM metabolism (Gnmt and Foxo) in D. melanogaster exposed to three chemicals, 2-phenylethanol, ethanol, and acetic acid. As a result, above genes were induced in chemical-exposed fly, and this supports our hypothesis of chemical tolerance pathway in D. melanogaster.

The honey bee, Apis mellifera, has a defense system, including detoxification, antioxidation, and immunity pathways, against external stimulation such as chemicals, stress, and pathogens. However, pesticides, particularly neonicotinoids and butenolids, have been recently reported to alter physiological changes in honey bee. In this study, we investigated the expression levels of eight genes categorized into detoxification (CYPQ3), antioxidation (CAT and SOD2), and immune system (Abaecin, Apidaecin, Defensin1, Defensin2, and Hymenoptaecin), in five tissues (Head, Thorax, Gut, Fat body, and Carcass) of honey bee treated with three pesticides (Acetamiprid, Imidacloprid, and Flupyradifurone) using quantitative real-time PCR. Gene expression patterns was varied depending on the type of pesticides and tissues. However, among eight genes, the expression levels of CYPQ3 was notably induced, but those of AMPs were generally reduced by all pesticides tested in this study in five tissues. These suggest that CYPQ3-mediated detoxification pathway is induced, but AMP-mediated immune system might be disrupted when honey bee is exposed to neonicotinoids and butenolid.

The adult of honey bee, Apis mellifera, performs an age-dependent division of labor with nurse bees and foragers. Foragers fly outside the hive to collect pollen and nectar, while nurses feed and care for the larvae and queen inside the hive. Foragers are considered to be frequently exposed to agrochemicals, although nurses, stayed inside the hive, are potentially exposed to pesticides through application of miticides and pesticidecontaminated food provided by forager. Therefore, physiological effects of pesticides to nurses should be elucidated to understand the adverse effects of the chemicals on entire honey bee colony. In this study, we investigated the expression changes of the genes associated with labor division (task genes) and the nursing behavior of nurse bees fed four pesticides: acetamiprid (ACE), carbaryl (CB), imidacloprid (IMI), and fenitrothion (FEN). When nurses were exposed to ACE, IMI, and FEN, expression levels of task genes were up- and down-regulated, and their nursing behaviors were also suppressed and enhanced, respectively. CB did not alter the gene expression levels, however increased nursing behavior. These suggest the potential of pesticide that breaks the balance of labor distribution in honey bee colony.

Ixodidae에 속하는 일부 참진드기들은 중증열성혈소판감소증후군(severe fever with thrombocytopenia syndrome; SFTS)을 비롯한 질병을 매개하는 공중보건학적으로 중요한 해충이다. 우리나라에서는 2013년 이후로 SFTS 환자 발생수가 지속적으로 증가하는 경향을 보이며, 경상북도는 전국적으로 2번째로 많은 SFTS 환자가 발생하는 지역이다. 본 연구에서는 2019년 경북 상주 지역의 진드기 분포를 조사하기 위해 시민의 생활 반경 주변을 도심 녹지지역, 관리 취약지역 및 농촌지역으로 구별하여 flagging 방법을 통해 진드기를 채집하였고, 채집 진드기내 SFTS 바이러스 보균 여부를 조사하였다. 채집된 진드기 수를 Collection Index (CI = tick number / 1h / 2 people)로 산출한 결과, 상주시 내 총 26개 지점에서 작은소피참진드기와 개피참진드기, 일본참진드기를 포함하는 총 CI 143의 진드기가 채집되었고, 그 중 작은소피참진드기가 96.5%(CI 138)로 우점종으로 확인되었다. 채집된 진드기의 약 92%(131 CI)는 인적이 드물고 시청이나 관계 당국의 관리가 이루어지지 않는 관리 취약지역에서 채집되었으나, 도심의 녹지지역와 농촌 지역에서는 8.4%(CI 12)의 진드기만 관찰되었다. 총 CI 143의 진드기를 26개 pooling 한 후 SFTS 바이러스 존재 여부를 조사하였으나, 모두 음성으로 확인되었다. 본 연구의 결과는 지역주민들로 하여금 진드기 매개 질병으로부터 안전한 생활을 하기 위한 권고 자료로 활용할 수 있을 것으로 기대된다.

Drosophila melanogaster is mainly found in fermented and rotten fruits and is tolerant to chemicals emitted during the fermentation process. Its distinctive habitat suggests an evolutionary adaptation to environmental chemicals. In order to understand the physiological adaptation of D. melanogaster to the chemicals, we treated LC20 concentration of three chemicals (acetic acid, ethanol and 2-phenylethanol) and differential expression of the female whole body transcripts were compared with control fly (no chemical treatment). Compared to control fly, 94, 137 and 59 genes were up-regulated, while 85, 184 and 166 genes were down-regulated in acetic acid, 2-phenylethanol and ethanol treated flies, respectively. According to the KEGG enrichment analysis, genes categorized in metabolic pathway, Toll/IMD signaling pathway, lysosome and autophagy were ranked in the top groups of most changed gene sets after three chemical treatment. In addition, we selected 7 genes showing different expression levels in transcriptome analysis, and investigated their expression changes in the flies exposed to various concentration of three chemicals using quantitative PCR.

We monitored the population of Haemaphysalis longicornis, in Andong, Gyungbuk from April to November, 2018. Among total 2,994 ticks collected for 8 months, H. longicornis 1,677(56%), H. spp Larva 1,074(35.9%), H. flava 213(7.1%), Ixodes nipponensis 30(1.0%) were identified. In addition, considering the environment, 1,727(57.7%), 907(30.3%), 192(6.4%) and 168(5.6%) ticks were collected in the grassland, graves, copse, mountain path, respectively. In the pathogen diagnosis with PCR using SFTS virus specific primers, positive viruses were detected in H. longicornis, H. flava and H. spp from June to October. The minimum field infection rate of June, July, August, September and October were 0.4%, 0.8%, 1.2%, 0.8% and 2.3%. respectively.

The fruit fly, Drosophila melanogaster, is a good model organism in various areas of biological science. Since D. melanogaster has been thought to be adapted to the chemical stress environment caused by the overripen, decay and fermented fruits, identification of the genes involved in chemical tolerance and investigation of their expression patterns are essential for better understanding of the physiological evolution in D. melanogaster. For investigation of the gene expression level, quantitative real-time PCR (qRT-PCR) can be applied to quantify gene expression level and selection of reliable reference gene(s) for normalization is an accurate step. In the present study, therefore, we validated the expression stabilities of ten candidate reference genes using three softwares (geNorm, NormFinder and BestKeeper) in D. melanogaster exposed to different concentrations of acetic acid, ethanol and 2-phenylethanol. Although three programs resulted in slightly different gene stability ranks, but overall tbp encoding TATA box binding protein was most stable gene in acetic acid and ethanol exposed fly, while nd encoding NADH dehydrogenase was the most suitable reference gene in the case of 2-phenylethanol treatment. In the comparison of three chemical treatment condition, nd was also suggested to be most optimal reference gene. In addition, optimal number of reference gene for accurate normalization was calculated by geNorm pairwise analysis, and selection of multiple reference genes was suggested to be better for target gene normalization method than use of a single reference gene.

Drosophila melanogaster and Drosophila suzukii are the species of the family Drosophilidae. Although these two fruit flies are taxonomically close species, D. suzukii is thought to be evolutionally adapted to the flesh or maturing fruits, whereas D. melanogaster is adapted to more fermented environments. According to the previous studies, several environmental toxins, such as acetic acid, ethanol, methanol and phenylacetate, ect., have been identified from rotten fruit and fermentation procedures. Considering the differences of distinct habitat between two flies, D. melanogaster is hypothesized to exhibit higher tolerance to the chemical toxins than D. suzukii. Therefore, in this study, we compared the tolerance and susceptibility of two fruit flies to three chemicals (acetic acid, ethanol, 2-phenlyethano).