Five heat shock protein 70 (hsp70) isoforms (hsc70-3, hsc70-4, hsc70-5, hsc70cb, hsp70Ab) of Apis mellifera were identified from Honeybee genome database. Specific primers for each isoform were designed for the quantitative realtime RT-PCR analysis, then analyzed transcript levels of the abdomen of adult workers (3-4 weeks old) in respond to heat shock and imidacloprid ingestion. Heat shock at 45°C for 1 h induced all 5 genes but highest in hsc70cb, hsp70Ab. Ingestion of imidacloprid pesticide did not change any hsp70 isoforms at 33°C but those bees also highly responsive to heat shock at 45°C. In addition, expression level of each hsp70 isoform was various and heat shock response of each isoform was tissue-specific. For example, hsc70-3 was highest in midgut, hsc70-4 was in hypopharyngeal gland, but hsp70Ab was in fat bodies. However, heat shock response of all 5 isoforms was the highest in the fat body than brain, hypopharyngeal gland, midgut, flight muscle and integument. Our results provide information for the understanding of complicated protective mechanism of honey bee against thermal stress.

Indianmeal moth Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae) is an economical pest of stored grains and their products, causing severe loss by feeding and producing silken web containing frass and exuvia. An ectoparasitoid Bracon hebetor Say (Hymenoptera, Braconidae) attacks this pest as a natural enemy and induce paralysis and developmental arrest in it. At molecular level its venom induce many physiological changes in host P. interpunctella to make it suitable source of food and development for its young ones. To explore these physiological changes at molecular level in P. interpunctella, we observed expression level of different genes having different functions related to immunity, defense and development at different intervals followed by B. hebetor envenomation. Fifth instar day 5 old larvae of P. interpunctella were used in experiment. Our results showed that B. hebetor envenomation effect the gene expression differently in host P. interpunctella. This basic study will be the starting point to understand the role of envenomation in host regulation studies.

Due to its rapid development of resistance to nearly all arrays of acaricide, Tetranychus urticae is extremely hard to control using conventional acaricides. As an alternative control measure of acaricide-resistant mites, RNA interference (RNAi)-based methods have recently been suggested. A double-stranded RNA (dsRNA) delivery method using multi-unit chambers was established and employed to screen the RNAi toxicity of 42 T. urticae genes. Among them, the dsRNA treatment of coatomer I (COPI) genes, such as coatomer subunit epsilon (COPE) and beta 2 (COPB2), resulted in high mortality [median lethal time (LT50) = 89.7 and 120.3h, respectively]. The transcript level of the COPE gene was significantly (F3,9 = 16.2, P =0.001) reduced by up to 24% following dsRNA treatment, suggesting that the toxicity was likely mediated by the RNAi of the target gene. As a toxicity enhancement strategy, the recombinant dsRNA was generated by reciprocally recombining half-divided fragments of COPE and COPB2. The two recombinant dsRNAs exhibited higher toxicity than the respective single dsRNA treatments as determined using LT50 values (79.2 and 81.5h, respectively). This finding indicates that the recombination of different genes can enhance RNAi toxicity and be utilized to generate synthetic dsRNA with improved RNAi efficacy.

The genus of Cinara (Aphididae: Lachninae) live on the roots, trunk, branches, twigs, shoots or foliage of Coniferae and can be easily distinguished in having the very big body, apterae up to 5-6 ㎜ in length and short antennae which are shorter than half the body length. Most of species are monoecious without host alternation and attended by ants. Based on body appearance and COI gene sequence, we report Cinara cuneomaculata (Del Guercio) on Larix kaempferi, C. largirostris Zhang G. & W. Zhang on Pinus thunbergii and P. dnesiflora, C. smaragdina (Pashtshenko) on Abies holophylla and C. piceae on Juniperus rigida, for the first time in Korea.