Synergistic effect of venom, calyx and teratocytes of <i>Apanteles kariyai</i> on the inhibition of larval pupal ecdysis of the host, <i>Pseudaletia separata</i>

Wani, Munenori; Yagi, Shigemi; Tanaka, Toshiharu

doi:10.1111/j.1570-7458.1990.tb01420.x

Cited by 40 publications

(12 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…croceipes, the action is independent of any effect from parasitoid venom or calyx fluid. In contrast, Wani et al [33] showed that teratocytes from A. kariyui prevent larval-pupal ecdysis only in the presence of both venom and calyx fluid. As an alternative, the teratocytes could be synthesizing and releasing JH [34] which could keep ecdysteroid titers depressed via feedback mechanisms [29].…”

Section: Discussionmentioning

confidence: 90%

Juvenile hormone esterase activity and ecdysteroid titer in Heliothis virescens larvae injected with Microplitis croceipes teratocytes

Zhang

Dahlman

Gelman

1992

Arch Insect Biochem Physiol

View full text Add to dashboard Cite

Juvenile hormone esterase (JHE) activity in the hemolymph of 5th-instar Heliothis virescens larvae injected with Microplitis croceipes teratocytes was inversely related to the number of teratocytes injected. JHE activity in the hemolymph of larvae injected with 750 3-day-old teratocytes (the approximate number from one parasitoid embryo) was depressed to less than 5% of those levels found in control larvae. During the latter portion of the digging stage and in the burrowing-digging (BD) stage JHE activity in larvae treated with 350 teratocytes was approximately 40% of control values. However, injection of 180 teratocytes did not significantly affect JHE titers. Two-day-old teratocytes caused the greatest reduction in JHE titer with decreasing effects observed with injections of 3-to 6-day-old teratocytes. Nevertheless, because 2-day-old teratocytes were difficult to separate from host hemocytes, 3-day-old teratocytes were used in most of these studies. Injections of nonparasitired H. virescens hemolymph plasma, Micrococcus lureus bacterial cell walls, washed M. croceipes eggs, or teratocytes from Coresia congregata did not depress JHE titers. Teratocyte injections also significantly reduced growth of host fat body. Ecdysteroid titers in cell formation, day 2 (CF2) larvae injected as new 5th instars with 350 3-day-old teratocytes failed to increase, as compared to noninjected and saline-injected controls. An injection of 1 pg/larva of 20-hydroxyecdysone at the BD stage permitted normal pupation in 50% of the teratocyte-treated larvae as compared to 0% pupation for teratocyte-treated control larvae not treated with 20-hydroxyecdysone. Teratocytes seem to be responsible for the inhibition of JHE release and thus indirectly impact on ecdysteroid titers. o 1992 ~i~e y -L i s s , Inc.

show abstract

Section: Discussionmentioning

confidence: 90%

Juvenile hormone esterase activity and ecdysteroid titer in Heliothis virescens larvae injected with Microplitis croceipes teratocytes

Zhang

Dahlman

Gelman

1992

Arch Insect Biochem Physiol

View full text Add to dashboard Cite

show abstract

“…In addition, teratocytes, which are cells derived from the extraembryonic serosal membrane of many braconid parasitoids, are also released into the host hemocoel as the parasitoid hatches (Dahlman and Vinson, 1993). Many effects of parasitization on the hosts, such as altered hormonal titers or regulation, reduced weight gain and altered development, can be mimicked by injection of PDVs (Dover et al, 1987;Wani et al, 1990;Dushay and Beckage, 1993;Shelby and Webb, 1994;Fathpour and Dahlman, 1995) or teratocytes (Zhang and Dahlman, 1989;Wani et al, 1990;Zhang et al, 1992;Pennacchio et al, 1992). Thus, the PDVs and teratocytes appear to play important roles in altering host growth and development, although the precise mechanism(s) of host regulation remain unclear.…”

Section: Introductionmentioning

confidence: 98%

Down-regulation of juvenile hormone esterase and arylphorin production inHeliothis virescens larvae parasitized byMicroplitis croceipes

Dong

Zhang

Dahlman

1996

Arch. Insect Biochem. Physiol.

View full text Add to dashboard Cite

“…Furthermore, M. croceipes TCs delay host larval development, resulting in incomplete larva‐to‐pupa metamorphosis (Zhang & Dahlman, ). Larval development is also delayed in Pseudaletia separata treated with A. kariyai TCs (Wani et al ., ). A significant reduction in ecdysteroid titre in TC‐treated larvae explains the host developmental alteration (Zhang et al ., ).…”

Section: Discussionmentioning

confidence: 97%

Transcriptome of a specialized extra‐embryonic cell, teratocyte, and its host immunosuppressive role revealed by ex vivo RNA interference

Ali

Lim

Kim

2014

Insect Molecular Biology

View full text Add to dashboard Cite

The specialized wasp cells teratocytes (TCs) are derived from the embryonic serosal membrane of some parasitic hymenopteran insects. As a parasitic factor, TCs are multifunctional in host regulation, such as host nutritional deprivation, immunosuppression and developmental arrest; however, little is understood about their genetic constituents. The present study provides a comprehensive view of the genes expressed by TCs through a transcriptome analysis based on RNA sequencing technology. The assembled 34 686 contigs (>200 base pairs) were annotated into different functional categories, indicating a distinct distribution in gene transcripts compared with those of haemocytes and fat body. The TC transcriptome contained components of insulin signalling and biosyntheses of juvenile hormone and 20-hydroxyecdysone. TCs also expressed various groups of digestive enzymes, indicating that they have nutritional role for the growing parasitoid larvae in parasitism. Furthermore, through this transcriptome analysis two kinds of immunosuppressive serine protease inhibitors (serpins) and Rho GTPase-activating proteins (RhoGAPs) were annotated. To determine the biological functions of these factors, we devised ex vivo RNA interference (RNAi) by conducting knockdown of gene expression in in vitro-cultured TCs followed by injection of the treated TCs to test insects. Ex vivo RNAi revealed that some serpins and RhoGAPs expressed in TCs inhibited host cellular immunity. This study reports a transcriptome of the unique TC animal cell and its immunosuppressive genetic factors using ex vivo RNAi technology.

show abstract

Synergistic effect of venom, calyx and teratocytes of Apanteles kariyai on the inhibition of larval pupal ecdysis of the host, Pseudaletia separata

Cited by 40 publications

References 15 publications

Juvenile hormone esterase activity and ecdysteroid titer in Heliothis virescens larvae injected with Microplitis croceipes teratocytes

Juvenile hormone esterase activity and ecdysteroid titer in Heliothis virescens larvae injected with Microplitis croceipes teratocytes

Down-regulation of juvenile hormone esterase and arylphorin production inHeliothis virescens larvae parasitized byMicroplitis croceipes

Transcriptome of a specialized extra‐embryonic cell, teratocyte, and its host immunosuppressive role revealed by ex vivo RNA interference

Contact Info

Product

Resources

About