Bacillus thuringiensis (Bt) is a gram-positive bacterium that produces parasporal crystal proteins known as endotoxins or Cry proteins. The Cry protoxins are then cleaved by insect midgut proteinases to form active Bt toxins. The activated Cry protein then binds to specific receptors at the midgut epithelium. Cadherin-like and aminopeptidase N (APN) proteins are involved in Bt toxin binding by interacting sequentially with different toxin structures. Aminopeptidase N (APNs) from several insect species have been shown to be putative receptors for these toxins. We have characterized four different midgut APNs(APN1, APN2, APN3, APN4) cDNAs from S. exigua. Forward primers and reverse primers for confirmation of four different midgut APNs were designed based on their sequences cloned from the cDNA libraries. Quantitative RT-PCR procedures includes 42℃ for 20min (cDNA synthesis), 99℃ for 5min, and 35 cycles (94℃ for 1min, and 60℃ for 50 s) for collection. Four aminopeptidase N isoforms were confirmed with qRT-PCR. Sequence analysis was performed by BlastX search the National Center for Biotechnology Information(NCBI) nucleotide. Furthermore, double-stranded RNAs(dsRNAs) were synthesized. DsRNAs were determined for bioassay.

Bacillus thuringiensis kurstaki와 aizawai의 내독소단백질을 알카리용액 또는 트립신, 곤충소화액 드응ㄹ 처리하여 전기영동한 후 단백질팬턴을 비교하였다. 두 균주의 주요 결정단백질은 130kd와 64kd의 단백질이었으며, 소화액이나 효소로 처리한 경우 공통적으로 62kd의 활성독소가 생성되었다. 그러나, aizawai는 kurstaki에 비해 현저히 적은 양의 62kd 단백질을 생성하였다. 흰불나방의 유충이 Bacillus thuringiensis 독소를 섭식하였을 때 지방체를 비롯한 몇 가지 조직에서 45kd의 스트레스 단백질이 유발되었는데 이 단백질은 열충격이나 저온 충격시에도 마찬가지로 생성되었다.

"Chuyoung" as a new double cropping potato variety was bred in 2005 for table use through a cross between "Dejima" with short tuber dormancy and HRB-31 which is a tetraploid derived from an interspecific cross between "Russet Burbank" and Solanum phureja line. It was evaluated for short dormancy, growth and tuber characteristics every twice a year from 1997 to 2001. Regional yield trials were performed from 2002 to 2004 at three locations, Jeju, Namhae and Gangneung of Korea, respectively. Its tuber shape is oblong with yellow skin and flesh colors. Its dormant periods is 60~70days. It showed less incidence of physiological disorders such as cracking or knobs on tubers, and higher resistance to common scab by Streptomyces scabies compared to "Dejima". It has tall plant height and erect growth type with green-broad leaflets and white large inflorescence. Its average yields are 29.5 and 22.6 ton/ha at 90 days after planting in spring and autumn cropping, respectively. It also showed higher marketable yield due to the lower incidence of common scab and physiological disorders compared to "Dejima".