• Journal of Sericultural and Entomological Science
• /
• v.39 no.2
• /
• pp.161-168
• /
• 1997

To clarify the effect of anti-juvenile hormone analogue (AJH) on the larval ecdysis by feeding at early stage of the 4th instar, the total amount of protein and activity of chitinolytic enzymes in the integument of Bombyx mori were analyzed, PAGE pattern of the protein was observed and the morphological changes of integument during molting period were also observed and the morphological changes of integument during molting period were also observed by means of TEM. The total amount of protein was greatly increased in premolting, then reached maximum level just before ecdysis, and rapidly decreased after the larval ecdysis in the control, while in the AJH treatment, increased 12 hr later than the control and its maximum was only 82.6% of the control. Two specific proteins, which were presumed as the protein originated from endocuticle, also appeared 12 hr later than the control and were maintained to 132 hr after AJH treatment from the aspects of the Native- and SDS-PAGE patterns, although those of the control disappeared instantly after ecdysis. Chitinase and $\beta$-N-acetylglucosaminidase activities were also suppressed and delayed by AJH treatment. Furthermore, it was observed that the apolysis took place 12 hr later than the control but new epicuticle was not formed at least until 132 hr after AJH treatment. From these results, it is suggested that the larval molting process of silkworm develops 12 hr later than the control but new epicuticle was not formed at least until 132 hr after AJH treatment. From these results, it is suggested that the larval molting process of silkworm develops 12 hr later than the control by AJH treatment but no further processing takes place just after apolysis.

• Proceedings of the Korean Society of Sericultural Science Conference
• /
• 2004.10a
• /
• pp.85-86
• /
• 2004

• Journal of Sericultural and Entomological Science
• /
• v.34 no.2
• /
• pp.1-5
• /
• 1992

Crude fermentation broths of two bacterial isolates, S-11 and S-25, from about 200 soil samples, showed inhibitory activities against the crude chitinase prepared from alimentary canals of the silkworm, Bombyx mori, as well as against reagent chitinase from Streptomyces griseus, in vitro. The chitinase inhibitors also exhibited insecticidal activities by preventing larval-pupal ecdysis when these broths were injected into the silkworm larvae during spinning.

• The Korean Journal of Zoology
• /
• v.22 no.1
• /
• pp.19-25
• /
• 1979

To determine the metabolism of leucine during the cuticle formation and the sclerotization process in Pieris rapae L., $U-^3$H-leucine or $U-^4$C-tyrosine is injected into the haemolymph of newly molted pupa through dorsal cuticle of heart area. The results show that leucine as a common amino acid participates in the synthesis of cuticle protein over the first 3 hr after ecdysis. It is also shown that leucine in the haemolymph at ecdysis is freely being moved between major internal organs during the short time period post-ecdysis, providing the evidence for some involvements including haemolymph protein synthesis and storage of fat body and gut in metabolism of leucine.

• Journal of Sericultural and Entomological Science
• /
• v.33 no.2
• /
• pp.93-96
• /
• 1991

The "Manta"(Juvenile hormone analogue-Methoprene) was topically applied at 36.48 and 72 hrs after the fourth ecdysis to eri silkworm, Samia cynthia ricini with doses of 2.75$\mu\textrm{g}$/$m\ell$, 4/0$\mu\textrm{g}$/$m\ell$ and 8.0$\mu\textrm{g}$/$m\ell$. The eri silkworm responded to 2.75$\mu\textrm{g}$/$m\ell$ of "Manta" applied at 72 hrs after the fourth ecdysis, resulting in improvement of larval, cocoon, pupal and cocoon shell weigths.ocoon shell weigths.

• Journal of Sericultural and Entomological Science
• /
• v.13 no.2
• /
• pp.135-139
• /
• 1971

It is very important to make mounting numerous silkworms by their normal growth when considering the sericultural management. There were several studies on the utilization of repellent to the matured silkworms to mounting, studies concerning forcing maturity of silkworms were developed considerably after studies on the insect ecdysis hormone. Commercial named MSH(II) (Inoksterone) similar substance of ecdysterone and DAT repellent (Dodesil alcohl) were used for this study, and the results can be summarized as follows; 1. MSH (II) mixed with the mulberry leaves shown the matured effect on the growth of silkworms and increased amount of MSH (II) shortened the last stage in their growth. 2. MSH (II) mixed with the mulberry leaves when 5% of early matured silkworms appeared were most effective. 3. DAT was hastened their mounting. 4. Utilization of MSH (II) and DAT together were hastened silkworms mounting and those chemicals can be used practically in the silkworm rearing.

• Journal of the Korea Safety Management & Science
• /
• v.15 no.2
• /
• pp.233-242
• /
• 2013

Korea have been efforts to revitalize the national economy by concentrating for the industrialization about 60 years after the Korean war. A result of these efforts, We will enter to the advanced country as the current economic power. But, Our social structure under the Korean Confucianism cannot ecdysis, because we recognise to the academic ability rather than the competency ability. So, the current government is trying to build social skills by presenting the slogan for the ability to implement social policy. This research utilized by the Human Resources Development Service of Korea and the Ministry of Education statistics for the variables to determine the equivalence of the Korea Education and qualifications in order to achieve the government's efforts to meet the need to improve equivalency is to empirically.

• The Korean Journal of Zoology
• /
• v.25 no.2
• /
• pp.63-70
• /
• 1982

The activity, properties, and distribution of midgut protease during metamorphosis in Pieris rapae L. are determined using spectrophotometer, ultracentrifuge and agar gel electrophoresis. Proteolytic activity of midgut reaches the peak just before ecdysis in 5th instar and prepupal stages each but 1 day after ecdysis in pupal stage. Also, optimum pH of midgut protease is pH 8.0 in 5th instar stage, pH 6.5 in prepupal stage, and pH 8.5 immediately before emergence respectively. Protease is found mostly in midght tissue in 5th instar stage but thereafter until just before emergence the enzyme only in lumen contents, suggesting that protease is synthesized in midgut tissue during larval stage and then released into lumen during pupation period.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.10 no.1
• /
• pp.11-17
• /
• 2005

In our research to identify gene involved in the cuticle protein, we cloned a novel cuticle protein gene, ApCP15.5, from the Chinese oak silkmoth, Antheraea pernyi, larvae cDNA library. The gene encodes a 149 amino acid polypeptide with a predicted molecular mass of 15.5 kDa and a pI of 9.54. The ApCP15.5 contained a type-specific consensus sequence identifiable in other insect cuticle proteins and the deduced amino acid sequence of the ApCP15.5 cDNA is most homologous to Tenebrio molitor-C1B ($43\%$ protein sequence identity), followed by Locusta migratoria-76 ($42\%$ protein sequence identity). Northern blot and Western blot analyses revealed that the ApCP15.5 showed the epidermis-specific expression. The expression profile of ApCP15.5 indicated that the ApCP15.5 mRNA expression was detected in the early stages after larval ecdysis and larval-pupal metamorphosis, and its expression level was most significant on the first day of larval ecdysis and pupal stage. The ApCP15.5 was expressed as a 15.5 kDa polypeptide in baculovirus-infected insect cells.

• Korean journal of applied entomology
• /
• v.61 no.1
• /
• pp.15-28
• /
• 2022

Neuropeptides produced in neurosecretory cells are the largest group of insect hormones. They regulate various physiological functions, such as fat body homeostasis, feeding, digestion, excretion, circulation, reproduction, metamorphosis, and behavior throughout all life stages. The PRXamide peptide family (X, a variable amino acid) is a well-characterized neuropeptide component with a common amino acid sequence, PRXamide (NH₂), at the C-terminal end conserved across Insecta. The PRXamide peptides are classified into three subfamilies, each having diverse biological roles in insects: (1) pyrokinin (PK) includes the pheromone biosynthesis activating neuropeptide (PBAN) and the diapause hormone (DH), (2) the capability (CAPA) peptides, and (3) the ecdysis-triggering hormone (ETH). PBAN as a member of PK subfamily was first identified to stimulate pheromone biosynthesis in moths three decades ago. Since then, PBAN peptides have been extensively studied by various research groups from a broad spectrum of arthropods. In this paper, we briefly review insect PBAN molecules with emphasis on gene structure and expression, signal transduction, physiological mechanism in sex pheromone biosynthesis, and application for pest management.