Clostera Anachoreta Research Articles

Activities of lipoxygenase and phenylalanine ammonia lyase in poplar leaves induced by insect herbivory and volatiles

A study was conducted to explore the defense response in woody plants after insect herbivory. The activities of two enzymes, lipoxygenase (LOX), a key enzyme of jasmonate (JA) pathway, and phenylalanine ammonia lyase (PAL), a rate-limiting enzyme of phenylpropanoid pathway, were measured in the leaves of one-year-old poplar (Populus simonii × P. pyramidalis ‘Opera 8277’) cuttings after Clostera anachoreta larvae attack. The results show that the increased activities of LOX and PAL were found not only in the leaves wounded by C. anachoreta larvae but also in their upper systemic leaves, indicating that JA and phenylpropanoid pathways were activated, and the defense response was stimulated systemically. The increase in LOX and PAL activities in neighboring intact poplar cuttings suggested that there exists the interplant communication between poplar plants mediated by the herbivore-induced volatiles. Methyl jasmonate (MeJA) was also proved to be an airborne signal to induce defense response in P. simonii × P. pyramidalis ‘Opera 8277’ cuttings.

Effects of feeding Clostera anachoreta on hydrogen peroxide accumulation and activities of peroxidase, catalase, and ascorbate peroxidase in Populus simonii × P. pyramidalis ‘Opera 8277’ leaves

In response to Clostera anachoreta larvae attack, poplar (Populus simonii × P. pyramidalis ‘Opera 8277’) leaves produced a high level of hydrogen peroxide (H2O2). Histochemical localization revealed that H2O2 was mainly localized in herbivore-wounded zones and might spread through the veins. The activities of three H2O2-scavenging enzymes, i.e., peroxidase (POD), ascorbate peroxidase (APX), and catalase (CAT), were also enhanced in herbivore-wounded leaves, and exhibited an opposite pattern to the accumulation of H2O2. It was found that diphenylene iodonium chloride (DPI, a special inhibitor of NADPH oxidase) treatment significantly inhibited the accumulation of H2O2 induced by herbivory damage. Moreover, DPI treatment led to an obvious decrease in the activities of POD, APX, and CAT. The results indicated that NADPH oxidase contributed to the accumulation of H2O2 and the increase in activities of H2O2-scavenging enzymes in poplar leaves induced by herbivory damage. The balance between H2O2-production pathway and H2O2-scavenging enzymes led to the tolerable level of H2O2 acting in P. simonii × P. pyramidalis ‘Opera 8277’ cuttings in response to herbivory damage.

Two new cell lines originated from the embryos of Clostera anachoreta (Lepidoptera: Notodontidae): characterization and susceptibility to baculoviruses

Two cell lines designated CAF-Clan I and CAF-Clan II have been established from embryos of Clostera anachoreta (Lepidoptera: Notodontidae) in TNM-FH medium containing 10% inactivated fetal bovine serum. CAF-Clan I consists of a mixture of three cell types: spherical cells, spindle-shaped cells, and giant cells. Most of the cultured cells formed a suspension in the medium and were subcultured more than 60 passages. CAF-Clan II mainly consists of spindle-shaped and spherical cells which attached to the culture surface and have undergone more than 40 passages. The cell population doubling time at 27 degrees C of CAF-Clan I at passage 22 and CAF-Clan II at passage 24 was about 68.5 and 38.2 h, respectively. The chromosome number of both cell lines at passage 15 varied from 62 to 100 in the majority of cells, though a few cells exceeded 260 (n = 30). DNA amplification fingerprinting-polymerase chain reaction analysis confirmed that the origination of the two cell lines was C. anachoreta. The susceptibility of the cell lines to baculoviruses was tested. The results showed that CAF-Clan II was susceptible to infection of Autographa californica nucleopolyhedrovirus (AcMNPV) and Ecotropis oblique nucleopolyhedrovirus (EoNPV). Occlusion bodies (OBs) production was 129 +/- 4 OBs/cell and 124 +/- 15 OBs/cell for AcMNPV and EoNPV, respectively. CAF-Clan I was less susceptible to AcMNPV compared with CAF-Clan II, while non-permissive to EoNPV.

Location and phylogenetic analysis of the region immediately upstream of the granulin gene of the Clostera anachoreta granulovirus

The region immediately upstream of the granulin gene from Clostera anachoreta granulovirus ( ClanGV) was identified from hybridization experiments and sequenced. The sequence of 5122 nt EcoRI restriction fragment was presented and compared with the equivalent area in other GVs. Database searches showed that this region contained three open reading frames (ORFs) similar to the baculovirus genes ( egt, fgf and me53, respectively) and four ORFs unique to ClanGV genome. Phylogenetic trees of the baculovirus genes egt and me53 were constructed. These analyses indicated that ClanGV genes may be more closely related to CfGV, CpGV, ClGV, PoGV and AoGV than to PxGV and XcGV.

Insect-resistant mechanism of transgenic triploid of Chinese white poplar

The activities of antidotal enzymes and digestive enzymes of Clostera anachoreta (Fabricius) instar larvae, feeding on leaves of three kinds of insect-resistant clones of transgenic triploid of Chinese white poplar, after 4, 12, 24, 48, 72 and 96 h, were investigated. The results showed that, feeding on clone 7, the activity of esterase, carboxylesterase, and mixed-function oxidases in the midgut of the larvae was very much decreased. Feeding on clone 10, those results were less than those of clone 7 and there were few changes on the larvae, which fed on clone 26. The changes of the amylase in the midgut of larvae were the same as those described above. However, the activities of glutathione S-transferase and proteinase were complex, increased markedly after 24 h feeding on clone 7, and then declined rapidly. The same changes were taking place on the larvae feeding on clone 10. There were many slight changes in glutathione S-transferase of the larvae, feeding on clone 26; no changes occurred in the proteinases of the midgut. Thus, the antidotal enzymes and digestive enzymes in the midgut of the larvae were inhibited. This may be the main mechanism of the transgenic triploid of Chinese white poplar.

Characterization and partial genome sequence analysis of Clostera anachoreta granulovirus

The morphological and biological properties as well as partial genomic sequencing of a granulovirus isolated from Clostera anachoreta (Lepidoptera: Notodontidae), C. anachoreta granulovirus ( ClanGV), were carried out. The ovoidal occlusion bodies were 337 nm × 170 nm in size, and each granule contained one single rod-shape virion, with a mean size of 250 nm × 46 nm. Granulin had a molecular weight of approximately 30 kDa. ClanGV genome size was estimated as 104.34 kb based on the restriction fragments. The restriction pattern of the ClanGV genome was different from other GVs. A restriction fragment genomic library of ClanGV genome was constructed. The library consisted of nine SalI fragments, seven HindIII fragments and seven EcoRI fragments. One 4.8 kb fragment of the genome, digested by SalI, was sequenced and analyzed. This region was composed of eight unknown ORFs, two baculoviruses homologous gene ( vp1054 and lef10) and partial sequence of lef-8. The unknown ORFs included three unique to ClanGV, the other five ORFs were related to baculoviruses. The ORFs, located within this restriction fragment, were compared to homologues in other GVs. The results indicated that ClanGV, CpGV, ClGV, AoGV and PoGV had similar arrangement and orientation of the homologous ORFs. Phylogenetic analysis of VP1054 proteins from 20 baculoviruses indicated that ClanGV was more closely related to CpGV, ClGV, AoGV and PoGV than to other baculoviruses.