摘要：
Crossing Wolbachia‐infected males with uninfected females reduced the hatching rate by 28% compared with that when infected males were crossed with infected females. The number of eggs laid by Wolbachia‐free females was significantly lower than laid by infected females. Wolbachia had a dual effect on Velarifictorus aspersus reproduction, inducing incomplete cytoplasmic incompatibility and promoting the fertility of infected females. Abstract Wolbachia is a maternally inherited endosymbiont of the phylum α‐Proteobacteria that is found widely in arthropods and nematodes. Cytoplasmic incompatibility (CI) is the commonest endosymbiotic manipulation among arthropods, namely reduced embryo viability when Wolbachia‐infected males fertilize Wolbachia‐uninfected females. In this study, endosymbiont infection was investigated and crossing experiments were performed in the wing‐dimorphic cricket Velarifictorus aspersus (Walker) (Orthoptera: Gryllidae) to clarify the effects of Wolbachia on host reproduction. All the tested individuals were infected with two Wolbachia strains, wAsp‐a and wAsp‐f, which belong to supergroup A and supergroup F, respectively. There were no obvious differences in the duration of nymph development or the proportions of females between the Wolbachia‐infected and Wolbachia‐free lines. However, crossing Wolbachia‐infected males with uninfected females reduced the hatching rate by 28% compared with that when infected males were crossed with infected females. The number of eggs laid by Wolbachia‐free females was significantly lower than laid by infected females, either mating with infected males or uninfected males. These results suggest that Wolbachia induced incomplete CI and enhanced female fertility in V. aspersus. Because no homologous cifA and cifB genes, which are involved in CI, were found in supergroups C, D and F, it might be considered that the CI of V. aspersus was induced by strain wAsp‐a of supergroup A. Moreover, the significant increase in the density of wAsp‐a Wolbachia with nymph development might be related to the regulation of CI.
摘要：
Our study showed that the hemolymph juvenile hormone (JH) titer exhibited a high‐amplitude daily rhythm in long‐winged female Velarifictorus aspersus (Orthoptera: Gryllidae), a species showing wing dimorphism. The crickets utilized glycogen and trehalose as flight fuel. The high‐amplitude daily rhythm of the JH titer was correlated with biosynthesis of flight energy substances and flight ability; that is, an elevated JH titer promoted the biosynthesis of flight energy substances, resulting in the improvement of flight capacity. Abstract The cricket Velarifictorus aspersus (Walker) (Orthoptera: Gryllidae) exhibits a wing dimorphism mediating two distinct life‐history strategies during early adulthood; long‐winged (LW) females mainly invest resources in flight, whereas short‐winged (SW) females invest more heavily in reproduction than LW females. To understand the relationships among juvenile hormone (JH), flight capacity, and energy accumulation, the daily rhythm of JH titer and flight activity, the concentrations of flight energy substances, and the influence of exogenous JH on flight activity and flight energy substances were investigated in V. aspersus. The results showed that the hemolymph JH titer exhibited a high‐amplitude daily rhythm in 5‐day‐old LW V. aspersus females, and the JH titer rose about 10× at 18:00 hours (6 h before lights off) and dropped to baseline levels after lights off. The females flew inactively (i.e., they floated in the air) from 14:00 to 19:00 hours during the light period, whereas they had a stronger flight capacity in the initial photophase and before lights out. The flight ability of LW females with 20 μg μL−1 JH treatments was significantly improved during periods of flight inactivity. After the peak JH titer, the concentrations of glycogen and trehalose in the flight muscles increased significantly. The LW females treated with JH during the inactive flight period had a significant increase in glycogen after 1 h and trehalose after 3 h. These results suggested that the high‐amplitude daily rhythm of the JH titer was correlated with accumulation of flight energy substance and flight capacity; that is, an elevated JH titer promoted the biosynthesis of flight energy substances, resulting in improvement of flight capacity.
通讯机构：
[Yang Zeng] L;Laboratory of Insect Behavior and Evolutionary Ecology, College of Life Science and Technology, Central South University of Forestry and Technology, Changsha 410004, China<&wdkj&>Author to whom correspondence should be addressed.
摘要：
Simple Summary In wing dimorphic insects, long-winged (LW) females were generally considered to be potential migrants, whereas short-winged females were considered sedentary. The aim of this research was to investigate the flight ability of LW females in the wing dimorphic crickets Velarifictorus aspersus and examine the effect of flight on ovarian development in LW females with different flight capacities. We provide the first evidence that flight ability varied among LW females, and the critical flight time for switching from flight to reproduction varied among LW V. aspersus female crickets with polymorphic flight behavior. A trade-off between the capacity for flight and reproduction has been documented extensively in wing polymorphic female insects, thereby supporting the possible fitness gain due to flightlessness. However, most of these studies were conducted without considering the effect of flight behavior. In the present study, we assessed the flight duration by long-winged (LW) females in the cricket species Velarifictorus aspersus on different days after adult emergence and examined the effect of flight on ovarian development in LW females with different flight capacities. Our results showed that the flight capacity increased with age and peaked after 5 days. In addition, the flight capacity varied among individuals, where most LW females could only take short flights (sustained flight time < 10 min) and only a few individuals could take long flights (sustained flight time > 20 min). In LW female crickets demonstrating only short flights, repeated flying for 30 or 60 min significantly promoted reproductive development. However, in those capable of long flights, reproductive development was affected only after a flight of 60 min. The flight muscles degraded after the start of rapid reproduction in those with both short and long flights. Our results indicated that the critical flight time for switching from flight to reproduction varies among LW V. aspersus female crickets with polymorphic flight behavior.
摘要：
The transcriptomes of Agasicles hygrophila eggs and first instar larvae were analyzed to explore the olfactory mechanism of larval behavior. The analysis resulted in 135,359 unigenes and the identification of 38 odorant-binding proteins (OBPs), including 23 Minus-C OBPs, 8 Plus-C OBPs, and 7 Classic OBPs. Further analysis of differentially expressed genes (DEGs) revealed 10 DEG OBPs, with 5 (AhygOBP5, AhygOBP9, AhygOBP12, AhygOBP15 and AhygOBP36) up-regulated in first instar larvae. Verification of expression patterns of these 5 AhygOBPs using qPCR showed that AhygOBP9 and AhygOBP36 were mainly expressed in the adult stage with gradually increasing expression in the larval stage. AhygOBP5, AhygOBP12, and AhygOBP15 were not expressed in eggs and pupae, and their expression in larvae and adults showed no clear pattern. These 5 AhygOBPs may play an olfactory role in larval behavior, providing a basis for further investigation of their specific functions and clarifying the olfactory mechanism of A. hygrophila.
摘要：
Mitochondrial genomes (mitogenomes) have been widely used in comparative and evolutionary genomics, molecular evolution, phylogenetics, and population genetics, but very limited information is available for the family Cynipidae. In this report, we describe the mitogenome of Dryocosmus liui Pang, Su et Zhu, providing the first complete mitogenomic data for a cynipid gall wasp species. The mitogenome of D. liui is 16,819 bp in length, and contains the typical set of 37 genes. Two control regions were detected, with the second being a perfect inverted repeat of the major portion of the first. Gene rearrangements were found in transfer RNA (tRNA) genes, protein-coding genes (PCGs) and ribosomal RNA (rRNA) genes, compared with the putative ancestral mitogenome. Similar to two other Cynipidae species with mitogenome data available, D. liui has a novel tRNA gene cluster trnL1-trnI-trnL2-trnW-trnM-trnQ between nad1 and nad2. Phylogenetic analysis based on sequences of PCGs and rRNA genes with D. liui included obtained topologies identical to previous studies supporting the a relationship of (Cynipoidea , (Platygastroidea, Proctotrupoidea)) within the monophyletic Proctotrupomorpha and (Cynipidae, Figitidae), Ibaliidae) within the Cynipoidea.
摘要：
The bamboo grasshopper, Ceracris kiangsu Tsai, is a serious pest of bamboo in China and Southeast Asia, and it overwinters as eggs for a period of up to 9 mo. Despite its importance, cold tolerance has not been thoroughly examined in this species. Thus, the present study investigated the low-temperature tolerance of overwintering eggs collected in the field, particularly the effects of rapid cold-hardening (RCH) and cold acclimation (ACC) on egg survival, and changes in the cryoprotectant contents. The supercooling point of overwintering eggs collected from the field was -23.9 & DEG;C, and their survival rate after exposure to -22 & DEG;C for 6 h was 26.6%, thereby suggesting that the cold tolerance strategy employed by C. kiangsu is freeze avoidance. After exposure to 0 and 4 & DEG;C for 12 and 24 h, or 0, 4, and 8 & DEG;C for 5 days, the survival rate of eggs subjected to -22 & DEG;C increased to approximately 50%, with significant effects of RCH and ACC. The glycerol levels in RCH and ACC treated eggs were also significantly higher than those in the control group, but the protein and trehalose contents were either reduced or not significantly altered. These results indicate that glycerol functions as a low molecular weight cryoprotectant in C. kiangsu eggs, and that RCH and ACC treatment facilitate its accumulation, thereby enhancing cold tolerance. Furthermore, the correlation between RCH and ACC was investigated. Graphical Abstract
作者机构：
[Zhang, Jiu-Yun; Zhu, Dao-Hong; Zeng, Yang] Cent South Univ Forestry & Technol, Coll Life Sci & Technol, Lab Insect Behav & Evolutionary Ecol, Changsha 410004, Hunan, Peoples R China.
通讯机构：
[Zeng, Y.; Zhu, D.-H.] L;Laboratory of Insect Behavior and Evolutionary Ecology, College of Life Science and Technology, Central South University of Forestry and Technology, Changsha, China
摘要：
SW males sang more often than LW males in crickets Velarifictorus aspersus. Flying could have induced more investment in calling behaviour by LW males. Songs produced by dealate LW males and LW males after flying for 30 min were more attractive than those of SW males. Singing activity and female preference of wing dimorphic male cricket, Velarifictorus asperses. Abstract A trade‐off between flight and reproduction has been well studied in wing dimorphic female insects but less attention has been given to this trade‐off in males. In this study, the authors analysed the differences in the calling behaviours of long‐winged (LW) and short‐winged (SW) male Velarifictorus aspersus crickets. Furthermore, the authors examined the effects of flight and wing dealation on the calling behaviour of LW males, as well as female preferences regarding the calling songs of males. The results showed that SW males sang more often than LW males during the first 9 days after emergence, but there were no significant differences in the song characteristics of SW and LW males. A flight of 5 min increased the singing time by LW males without changing the song characteristics, but a flight of 30 min or wing dealation increased both the singing time and chirp number per song. In binomial choice trials, female crickets did not prefer SW calling song to unflown LW calling song. But when LW males had either flown 30 min or been dealated, females preferred LW to SW calling song. Therefore, LW males may attract fewer females than SW males when they are preparing for dispersal, but this reproductive disadvantage may be absent during dispersal and the settling stage.
期刊：
Frontiers in Microbiology,2022年13:865227 ISSN：1664-302X
通讯作者：
Zhu, D.-H.
作者机构：
[Su, Cheng-Yuan; Gao, Shuo; Zhu, Dao-Hong; Ren, Ye-Song] Laboratory of Insect Behavior and Evolutionary Ecology, College of Life Science and Technology, Central South University of Forestry and Technology (CSUFT), Changsha, China
通讯机构：
[Zhu, D.-H.] L;Laboratory of Insect Behavior and Evolutionary Ecology, China
摘要：
Wolbachia is a maternally inherited bacterium that is widely distributed among arthropods, in which it manipulates the reproduction of its hosts. Phage WO is the only bacteriophage known to infect Wolbachia, and may provide benefit to its host or arthropods. We screened for the presence of phage WO in Wolbachia-infected butterfly species for the first time, to investigate their diversity and evolutionary dynamics. All Wolbachia-infected butterfly species, including members of the families Hesperiidae, Lycaenidae, Nymphalidae, Papilionidae, and Pieridae, were found to harbor phage WO. Interestingly, 84% of 19 butterfly species, which were infected with a single Wolbachia strain harbored high levels of multiple phage types (ranging from 3 to 17 types), another three species harbored one or two phage types. For Wolbachia strains (ST-41, ST-19, ST-125 and ST-374) shared among various butterfly species, their host insects all harbored multiple phage types, while two Wolbachia strains (ST-297 and ST-wPcau) were found to infect one butterfly species, whose insect hosts harbored a single phage type, suggesting that horizontal transfer of Wolbachia between insects increased the likelihood of exposure to phages, resulting in increased phage genetic diversity. Twelve horizontal transmission events of phage WO were found, which shared common phage WO types among different Wolbachia strains associated with butterflies. Most horizontal transfer events involved different Wolbachia supergroups (A and B). Horizontal acquisition of phage WO might also occur between eukaryotes without Wolbachia transfer. Furthermore, 22 putative recombination events were identified in 13 of 16 butterfly species which harbored multiple phage types. These results showed that horizontal transfer of Wolbachia caused it to be exposed to the phage gene pool, and that horizontal transmission of phage WO, as well as intragenic recombination were important dynamics for phage WO genome evolution, which effectively promoted the high level of phage WO diversity associated with butterflies.
期刊：
Journal of Asia-Pacific Entomology,2022年25(4):101987 ISSN：1226-8615
通讯作者：
Dao-Hong Zhu
作者机构：
[Zhu, Dao-Hong; Zhong, Jia-Lian] Cent South Univ Forestry & Technol CSUFT, Coll Life Sci & Technol, Lab Insect Behav & Evolutionary Ecol, Changsha 410004, Hunan, Peoples R China.
通讯机构：
[Dao-Hong Zhu] L;Laboratory of Insect Behavior and Evolutionary Ecology, College of Life Science and Technology, Central South University of Forestry & Technology (CSUFT), Changsha, Hunan 410004, China
关键词：
Andricus mairei;Mitochondrial genome;Gene rearrangement;Control region
摘要：
Mitochondrial genomes (mitogenomes) have been used widely in comparative and evolutionary genomics, molecular evolution, phylogenetics, and population genetics, but very limited information is available for the family Cynipidae. In this report, we described the mitogenome of Andricus mairei. The mitogenome of A. mairei was 16,514 bp in length and contained a typical set of 37 genes. Two control regions (CRs) were detected, one being a partial reverse repeat of the other. In a comparison with the putative ancestral mitogenome, gene rearrangements were found in transfer RNA (tRNA) genes, protein-coding genes and ribosomal RNA (rRNA) genes. Consistent with other Cynipidae species, the gene rearrangement of A. mairei had four obvious charac-teristics: trnE and trnF had inverted and swapped positions; rrnL and rrnS genes had moved into the cob-nad1 junction; a novel tRNA gene clustertrnL1-trnI-trnL2-trnW-trnM-trnQ had been formed between nad1 and nad2; and trnV had inverted and moved to the nad2-cox1 gene junction. Furthermore, A. mairei had two types of mitochondrial circular DNA molecules. Type II differed from type I in an inverted rearrangement of a large fragment of 3349 nucleotides, including two CRs and two rRNA genes.
通讯机构：
Laboratory of Insect Behavior and Evolutionary Ecology, College of Life Science and Technology, Central South University of Forestry and Technology (CSUFT), Hunan, China
摘要：
The availability of resources can have important effects on the fighting behaviors of insects, but the physiological mechanism that might underlie the effect of resources is unclear. Nitric oxide (NO) is a gaseous neurotransmitter that is capable of directly diffusing into cells and acting as a messenger. Several studies have reported that NO may be involved in modulating the fighting behavior of insects. In the present study, we investigated the effect of different resources on the fighting behavior of Velarifictorus aspersus Walker male crickets (Orthoptera: Gryllidae), and tested whether this effect is regulated by NO. We found that when a burrow or female was available, the fighting level and fighting duration were significantly greater in males compared with those when no resources were available, thereby suggesting that the presence of a valuable resource motivated male crickets to fight more aggressively. In a novel environment, treatment with an NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) significantly increased the fighting level and fighting duration in male crickets, and males treated with L-NAME won more fights against males treated with water. However, when a burrow or female was available, treatment with L-NAME did not affect the fighting level and fighting duration in males, and males treated with L-NAME lost more fights against males treated with water. These results suggest that NO may have different effects on modulating the fighting behavior of male V. aspersus crickets under different resource conditions.
作者机构：
[Pang, Yin; Zhu, Dao-Hong; Su, Cheng-Yuan; Zhu, Jun-Qiao; Zhong, Jia-Lian] Cent South Univ Forestry & Technol, Coll Life Sci & Technol, Lab Insect Behav & Evolutionary Ecol, Changsha 410004, Hunan, Peoples R China.;[Yang, Xiao-Hui] Hunan Normal Univ, Sch Life Sci, Changsha 410081, Hunan, Peoples R China.;[Liu, Zhiwei] Eastern Illinois Univ, Biol Sci Dept, Charleston, IL 61920 USA.
摘要：
In the present paper, a new species of cynipid gall wasp, Andricus elodeoides Liu & Pang, is described from several provinces in southern China. The new species is closely related to the recently redescribed A. mairei (Kieffer, 1906). In addition to differences in adult and gall morphology, the new species is also readily separated by COI sequences, with a 6.2-8.9% genetic distance between populations of the new species and those of A. mairei. A contrasting difference in sex ratios was also observed between the two species, with A. elodeoides extremely female-biased (95.5-97.8% female) while A. mairei male-biased to more balanced (5.4-43.5% female). PCR screening for Wolbachia infection further revealed contrasting infection rates between populations ofA. elodeoides and A. mairei: the Wolbachia infection rate was 0% in A. elodeoides and 100% in A. mairei. Cytoplasmic incompatibility induced by Wolbachia is proposed as a potential mechanism of speciation of the sympatric A. elodeoides and A. mairei.
作者机构：
[Yang, Xiao-Hui; Li, Xiang-Mei] Hunan Normal Univ, Coll Life Sci, Key Lab Prot Chem & Dev Biol Fish Educ, State Key Lab Dev Biol Freshwater Fish,Minist Chi, Changsha 410081, Peoples R China.;[Zhu, Dao-Hong; Zeng, Yang] Cent South Univ Forestry & Technol, Lab Insect Behav & Evolutionary Ecol, Changsha 410004, Peoples R China.;[Zhao, Lv-Quan] Nanjing Forestry Univ, Coll Forestry, Coinnovat Ctr Sustainable Forestry Southern China, Nanjing 210037, Peoples R China.
通讯机构：
[Xiao-Hui Yang] K;Key Laboratory of Protein Chemistry and Developmental Biology of Fish of Education Ministry of China, State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha 410081, China<&wdkj&>Author to whom correspondence should be addressed.
摘要：
Simple Summary Dryocosmus kuriphilus is an invasive pest species which is native to China and is widely distributed in Asia, Europe and North America. D. kuriphilus induces insect galls on chestnut trees, and fungi can cause the necrosis of chestnut trees and the death of D. kuriphilus. The aim of this research was to investigate the potential role of D. kuriphilus in the transmission of fungi. We provide the first evidence that D. kuriphilus adults shared most fungal species with associated insect galls and the galled twigs of Castanea mollissima, and were dominated by Botryosphaeria sp., Aspergillus sp. and Diaporthe sp. Furthermore, we suggest that D. kuriphilus adults may be potential vectors of plant pathogens and mediate the transmission of fungi between chestnut trees. Dryocosmus kuriphilus (Hymenoptera: Cynipidae) is a gall wasp that induces insect galls on chestnut trees and results in massive yield losses worldwide. Fungi can cause the necrosis of chestnut trees and the death of gall wasps. The aim of this research was to investigate the potential role of D. kuriphilus in the transmission of fungi. We sequenced the ribosomal RNA internal transcribed spacer region 1 of fungi in D. kuriphilus adults, associated insect galls and the galled twigs of Castanea mollissima, using high-throughput sequencing. We compared the species richness, alpha-diversity and community structure of fungi in D. kuriphilus adults, insect galls and the galled twigs. We provide the first evidence that D. kuriphilus adults shared most fungal species with associated insect galls and the galled twigs, and were dominated by Botryosphaeria sp., Aspergillus sp. and Diaporthe sp. We suggest D. kuriphilus adults may be potential vectors of plant pathogens and may facilitate the transmission of fungi between chestnut trees. Furthermore, the fungi may horizontally transmit among D. kuriphilus adults, associated insect galls and the galled twigs.
通讯机构：
[Dao-Hong Zhu] L;Laboratory of Insect Behavior and Evolutionary Ecology, College of Life Science and Technology, Central South University of Forestry & Technology (CSUFT), Changsha, Hunan 410004, China
摘要：
Wolbachia are endosymbiotic bacteria that are widely present in nematodes and arthropods and sometimes have a significant impact on the evolution, ecology, and biology of their hosts. The co-occurrence of Wolbachia within both Cynipid gall wasps and their parasitoids has rarely been studied. In this study, we report the occurrence of six species of gall wasps and 10 species of their parasitoids in central China. Wolbachia detection using the wsp gene showed that Wolbachia infected two species of gall wasps as well as their parasitoids, indicating that horizontal transmission of Wolbachia occurs between gall wasps and their parasitoids. Given that parasitoids will kill their hosts, Wolbachia may be horizontally transferred from gall wasps to their parasitoids. Using multilocus sequence typing (MLST) analysis, five new strains of Wolbachia were identified, all of which belonged to supergroup A. The strains of Wolbachia that infected gall wasps were not the same as those that infected their parasitoids. This result indicated that Wolbachia may evolve independently in parasitoids after they have been transferred from the host gall wasps.
期刊：
PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON,2021年123(3):465-473 ISSN：0013-8797
作者机构：
(YA) Faculty of Social and Cultural Studies, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan (e-mail:;http://zoobank.org/4ACD6B0F-34B1-449B-A351-64D297CB2868);(TI) Department of Zoology, National Museum of Nature and Science, 4-1-1 Amakubo, Tsukuba, Ibaraki 305-0005, Japan (http://zoobank.org/3DD227A9-F54D-4821-94FA-86C02127408F);(CYS and DHZ) Laboratory of Insect Behavior and Evolutionary Ecology, College of Life Science and Technology, Central South University of Forestry & Technology (CSUFT), Changsha, Hunan 410004, China;(CYS: http://zoobank.org/AF6E30D8-B1E0-4B53-BF36-F954323236CC
摘要：
A new species in the genus Latuspina (Hymenoptera: Cynipidae) that induces galls on the leaves of Quercus variabilis Blume (Fagaceae) in China is described here as Latuspina jinzhaiensis Abe, Ide, Su, and Zhu, new species. The sexual generation gall of the new species is indistinguishable from that produced by L. abemakiphila Ide and Abe, which is induced on leaves of the same oak species in Japan. However, these two cynipid species can be distinguished based on the morphological characteristics of the propodeum of adult wasps. Moreover, differences in the partial sequence of the mitochondrial cytochrome c oxidase subunit I (COI) gene (18–19 of 658 bp) supports the morphological distinction between these two species. Although congeneric gall-inducing cynipids, as well as other gall-inducing insects such as gall midges, can typically be distinguished based solely on gall characteristics (e.g., shape and position on the plant) and host plant species, these two Latuspina species are an exception. Since the asexual generations of both species are currently unknown, finding asexual generation galls and adults in the future is considered necessary.
期刊：
Frontiers in Microbiology,2021年12:694115 ISSN：1664-302X
通讯作者：
Zhu, D.-H.
作者机构：
[Zhu, Dao-Hong; Su, Cheng-Yuan] Cent South Univ Forestry & Technol, Coll Life Sci & Technol, Lab Insect Behav & Evolutionary Ecol, Changsha, Peoples R China.;[Yang, Xiao-Hui] Hunan Normal Univ, Coll Life Sci, Changsha, Peoples R China.;[Abe, Yoshihisa] Kyushu Univ, Fac Social & Cultural Studies, Fukuoka, Japan.
通讯机构：
[Zhu, D.-H.] L;Laboratory of Insect Behavior and Evolutionary Ecology, China
摘要：
The phage WO was characterized in Wolbachia, a strictly intracellular bacterium causing several reproductive alterations in its arthropod hosts. This study aimed to screen the presence of Wolbachia and phage WO in 15 gall wasp species from six provinces of southern China to investigate their diversity and prevalence patterns. A high incidence of Wolbachia infection was determined in the gall wasp species, with an infection rate of 86.7% (13/15). Moreover, seven species had double or multiple infections. All Wolbachia-infected gall wasp species were found to harbor phage WO. The gall wasp species infected with a single Wolbachia strain were found to harbor a single phage WO type. On the contrary, almost all species with double or multiple Wolbachia infections harbored a high level of phage WO diversity (ranging from three to 27 types). Six horizontal transfer events of phage WO in Wolbachia were found to be associated with gall wasps, which shared identical orf7 sequences among their respective accomplices. The transfer potentially took place through gall inducers and associated inquilines infected with or without Wolbachia. Furthermore, 10 putative recombination events were identified from Andricus hakonensis and Andricus sp2, which harbored multiple phage WO types, suggesting that intragenic recombination was the important evolutionary force, which effectively promoted the high level of phage WO diversity associated with gall wasps.
摘要：
Simple Summary Andricus hakonensis is thought to contain the most complex and diverse phage types known and should be an ideal model material for studying interactions among bacteriophages, bacteria and eukaryotes. As shown in previous studies, existing primers are not effective enough to amplify all virus groups in A. hakonensis. Based on a comprehensive analysis of all virus groups reported to date, we designed a relatively conservative primer for virus detection. This primer can accurately and efficiently detect the presence of phage WO in arthropod hosts. Using gene alignment, clear evidence was provided for the existence of hitherto unreported base deletions, which are an important cause of diversity in phage WO associated with A. hakonensis. Phage WO was first characterized in Wolbachia, an obligate intracellular Rickettsiales known for its ability to regulate the reproduction of arthropod hosts. In this paper, we focus on the study of virus diversity in Andricus hakonensis and the development of highly effective primers. Based on the existing Wolbachia genome sequence, we designed primers (WO-TF and WO-TR) to amplify the full-length orf7 gene of phage WO. Surprisingly, sequencing results showed a high abundance of other phage WO groups in A. hakonensis, in addition to the four groups previously identified. The results also showed that A. hakonensis contained most of the known types of orf7 genes (I, III, IV, V and VI) and the level of diversity of harbored phage WO was very high. Therefore, we speculated that existing primers were not specific enough and that new primers for the detection of phage WO were needed. Based on the existing orf7 gene sequence, we designed specific detection primers (WO-SUF and WO-SUR). Sequencing results showed that the primers effectively amplified all known types of phage WO. In addition to amplifying most of the known sequences, we also detected some new genotypes in A. hakonensis using the new primers. Importantly, all phage WO groups could be efficiently detected. Combined with the results of previous studies, our results suggest that A. hakonensis contains the largest number of phage types (up to 36 types). This study is novel in that it provides practical molecular evidence supporting base deletions, in addition to gene mutations and genetic recombination, as an important cause of phage WO diversity.
通讯机构：
[Yang Zeng; Dao-Hong Zhu] L;Laboratory of Insect Behavior and Evolutionary Ecology, College of Life Science and Technology, Central South University of Forestry & Technology (CSUFT), Changsha, Hunan 410004, China
摘要：
Microsatellite markers have been used extensively in studies of sperm competition and the genetic diversity of organisms. In the present study, we performed transcriptome sequencing for Velarifictorus aspersus and developed simple sequence repeat markers to identify valuable markers for genetic studies. The average total length of the V. aspersus transcriptome sequence was 7.70 Gb and it contained 7878 microsatellite loci. Sixty-four microsatellite loci were randomly selected for primer design and 39 loci were successfully amplified, among which 23 loci were polymorphic. The microsatellites were also tested in six other species from the Gryllidae family. Among the species belonging to the genus Velarifictorus, 22 loci were amplified in Velarifictorus micado, eight loci in Velarifictorus ornatus, and 3–6 loci in the other four cricket species.
