The use of genetically closely related populations as reintroduction sources is crucial in restoration programmes for endangered species because genetically distant populations may cause genetic disturbances. Aporia hippia (Lepidoptera; Pieridae) is an endangered subalpine grassland butterfly in Japan and its distribution area is restricted to the Asama, Yatsugatake and Akaishi Mountains in central Honshu Island. In the Yatsugatake Mountains, its population is probably already extinct, and reintroduction from the other sites is now under consideration. Here, we estimated the genetic diversity and spatial genetic structure of A. hippia in Japan to identify candidate source populations for reintroduction in extinct populations via multiplexed inter-simple sequence repeat genotyping by sequencing (MIG-seq) and mitochondrial DNA sequencing methods. The MIG-seq method indicated the presence of very few genetic differences among the populations. The mitochondrial DNA sequencing method identified two haplotypes: haplotype A in the Asama, Yatsugatake and northern Akaishi Mountains, and haplotype B in the central and southern Akaishi Mountains. The two haplotypes exhibited only a one base pair substitution between them. Implications for insect conservation: Based on these results, we suggest the existence of two conservation units: the first group consisting of populations in the Asama, Yatsugatake, and northern Akaishi Mountains, and the second group consisting of those in the central and southern Akaishi Mountains. According to this genetic proximity, however, all populations of A. hippia in Japan can also be defined as one conservation unit group, given the risk of inbreeding depression or difficulty of adaptation in different environments.

While the colonization processes of arthropods in new volcanoes have attracted our attention, the arthropod assembly process in sites where vegetation reaches climax forests after the Holocene catastrophic eruption is unknown. In this study, ground beetles and spiders were investigated using pitfall traps in 12 sites from the subalpine and alpine areas of Mt. Fuji, which were shaped about 2300 years ago and where undisturbed subalpine climax forests and alpine deserts are formed. We examined how elevation, canopy and forest floor vegetation affected turnover and nestedness structure of these assemblages. The alpine desert and subalpine forest comprised different species for both beetles and spiders. The species from the alpine desert seemed to have high dispersal ability. In the subalpine forest, the beetle assemblage found at higher elevations was a subset of those at lower elevations. This nested structure was generated by the expansion of flightless species from montane forests to subalpine forests. Species tolerance to harsh weather conditions may decide the upper elevational limit. The spider assemblage was affected by forest floor vegetation, where species turnover was observed between different floor types. Subalpine spiders included both species expanding from the montane area and those probably colonizing from distant subalpine areas by ballooning. These results suggest that the assembly process differed between alpine and subalpine areas, and also between different taxa particularly in subalpine forests. Examining the genetic relationship between Mt. Fuji populations and possible source populations in other mountains will elucidate the detailed community assembly process in Mt. Fuji.

The green anole (Anolis carolinensis) is on the list of the designated invasive alien species in Japan because of its negative effects on indigenous entomofauna. Therefore, control operations of the lizard are being carried out in some areas on the Ogasawara Islands. The primary population-control measure is the use of adhesive traps on tree trunks. Identification of the characteristics of the tree trunk type that this lizard uses frequently will contribute to effective setting of the traps, thereby improving catchability. To clarify whether or not there is a perching site preference according to plant species, we evaluated the available (n=1,228) and observed (n=811) perching sites in terms of tree species. A lizard food resource survey was also conducted on four major plant species. As for the selectivity of plant species, the screw pine (Pandanus boninensis) was strongly preferred by adult and juvenile anoles (P<0.05). Food availability is not considered to be the rationale for the anoles' preference of the screw pine, because the number of arthropods collected at the screw pine was not larger compared to those on other plant species examined.

We report herein on the case of a 54-year-old Japanese male diagnosed as having Rickettsia disease based on the detection of Rickettsia japonica in the blood crust from the biopsy scar of an eschar. In late September 2016, the patient suffered from a 39℃ fever and visited a hospital. He had an eschar on the right abdomen and a rash present over the whole body. Blood tests showed thrombocytopenia, severe inflammation,and mild liver dysfunction. A real-time PCR procedure detected Rickettsia japonica DNA in the blood crust from the biopsy scar of the eschar, suggesting Japanese spotted fever. He recovered well from the disease with the administration of minocycline and ciprofloxacin. The PCR detection of R. japonica DNA in the blood crust from a biopsy scar of an eschar can be a sensitive method for the early diagnosis of Rickettsia disease.

Severe fever with thrombocytopenia syndrome (SFTS), first reported in China in 2011, is caused by the SFTS virus (SFTSV), a phlebovirus belonging to the family Phenuiviridae, and is reportedly transmitted by species of ticks (1,2). The first case of SFTS in Japan was reported in 2013, and since then, 391 cases have been reported as of October 31, 2018. Patient notifications have mainly originated from the western region of Japan (1,2). This disease shows various symptoms, such as fever; general fatigue; gastrointestinal tract symptoms, including nausea, vomiting, and appetite loss; leukopenia; thrombocytopenia; and increased levels of aspartate aminotransferase, alanine transaminase, and lactate dehydrogenase. Some patients show rapid and severe progression, and the patient fatality rate in Japan is approximately 16% (1,2). Therefore, early diagnosis and treatment are necessary to improve disease prognosis. SFTS is a tick-borne infection, and SFTSV is maintained in ticks and mammals through tick–tick (vertical transovarial transmission) and tick– mammal cycles. SFTSV genomes have been detected in several tick species (e.g., Haemaphysalis longicornis and Amblyomma testudinarium) in Japan, which act as vectors for transmitting SFTSV to humans. A high prevalence of anti-SFTSV antibody seropositivity has been observed among deer, wild boars, dogs, and raccoons (1). The transmission of SFTSV through direct contact with blood and/or body fluids of a patient with SFTS to his or her family members or medical providers has been reported, and wild and domestic mammals are also believed to be sources of direct human transmission (1,3,4). Herein, we report on a patient with SFTS identified as developing a direct infection from a sick

Pesticides are frequently used to eradicate invasive ant species, but pose ecological harm. Previous studies assessed non-target effects only in terms of the increase or decrease of abundance or species richness after pesticide applications. Positive effects of the release from pressure caused by invasive ant species have not been considered so far. To more accurately assess pesticide effects in the field, the non-target effects of pesticides should be considered separately from the positive effects of such releases. Here, we used monitoring data of ants and other invertebrates collected in a program for the eradication of the Argentine ant, Linepithema humile (Mayr), using fipronil. First, we separately assessed the effects of L. humile abundance and fipronil exposure on non-target ants and other invertebrates using generalized linear models. The abundance of L. humile and the number of pesticide treatments were negatively associated with the total number of non-target individuals and taxonomic richness. We also noted negative relationships between the number of individuals of some ant species and other invertebrate taxonomic groups. The L. humile × pesticide interaction was significant, suggesting that the abundance of L. humile affected the level of impact of pesticide treatment on non-target fauna. Second, we evaluated the dynamics of non-target ant communities for 3 years using principal response curve analyses. Non-target ant communities treated with fipronil continuously for 3 years recovered little, whereas those treated for 1 year recovered to the level of the untreated and non-invaded environment.

In the original publication of the article, the Table 1 was incorrectly published. Tapinoma melanocephalum (TM) and Camponotus nipponicus (CN) were labeled incorrectly as "absence" and "presence" at Takeshiba, respectively. The correct version of the table is given below where TM is labelled as "presence" and CN is labelled as "absence".

Yersinia pseudotuberculosis 感染症の発生状況を把握するため，主に小児科患者等654 名（1,308 検体）の血清について，Y. pseudotuberculosis 血清群1～6 の各菌体抗原に対する抗体価を測定した．その結果，98名（15.0％）が1種類の血清群に対して抗体陽性（≧1：160）となり，このうち血清群5が42名（42.9％）で最も多かった．Y. pseudotuberculosis が便や血液から分離された事例においては，16名中13名（81.3％）が，また，環境のみから本菌が分離された3 事例の患者6名中5名（83.3％）が抗体陽性となり，陽性を示した抗体の血清群は各事例の分離菌の血清群と一致した．抗体陽性者は，川崎病症状を呈した患者グループ（10.9％）に比べ，Y. pseudotuberculosis 感染疑いの患者等のグループ（18.5％）に多く（p＜0.01），抗体陰性の者に比べて下痢，結節性紅斑，腹痛，腎不全の症状や，家族内発症及び山水・井戸水などの使用の割合が有意に高かった（p＜0.025～p＜0.005）．

This data paper reports census data of ground-dwelling beetle and other fauna of the forest floor environment; collections were made from a network of 22 forest sites in Japan. To our knowledge, this represents the largest dataset for long-term monitoring of a ground-dwelling beetle community and other taxa in a ground environment in forests, which covers a broad climatic range in the temperate zone and is freely available. The network forms part of the Monitoring Sites 1000 Project launched by the Ministry of the Environment, Japan. It covers subalpine, cool- and warm-temperate and subtropical climatic zones and the four major forest types of Japan. Thirty-three permanent plots usually 1 ha in size were established in old-growth, secondary natural and a few plantation forests. Censuses of the ground-dwelling beetle community were conducted using pitfall trapping and forest floor environment monitoring every year from 2004 to the present. During the initial 9 years of the census (2004–2012), 59,762 beetle individuals (including 3182 larvae) of more than 314 species were recorded. This dataset includes taxonomy and biomass of each beetle individual and each taxonomic group of other invertebrates coincidently captured in pitfall trapping. The dataset also includes data related to ground coverage by forest floor vegetation, dry mass of the accumulated organic litter layer, and carbon and nitrogen contents and cellulose decomposition rate in organic layer and surface mineral soil. The data could be used to investigate geographical patterns and intra- and inter-annual dynamics of individual body mass, populations and community structures of ground-dwelling beetles, and their relationships with the forest floor environment. Furthermore, the data could be analyzed with other open datasets related to tree community dynamics and litter fall continuously measured in the same study plots. This dataset also provides information related to the distribution and average body mass of each beetle species.

減少症候群 (severe fever with thrombocytopenia

In the last 30 years some limited successes in alien ant control have been documented globally, and control programs remain challenging. Moreover, the potential non-target impacts of toxicants have not been well studied. We assessed the efficacy and non-target effects of multiple products containing the active compound fipronil in the attempted control of two populations of the invasive Argentine ant Linepithema humile (Mayr) in Tokyo, Japan. Three treatments were conducted: control, low-dose treatment (0.1 g/ha per treatment), and high-dose treatment (0.2 g/ha). Treatments were applied once per month for 11 months. The abundance of L. humile declined rapidly by up to 99.8 % in treated areas, but remained at extremely high densities in the control area. The treatments had few negative non-target effects, with the abundances of native ant species and other ground-dwelling invertebrates except for cockroaches being greater in the treated areas after L. humile suppression. Thus, fipronil is an effective compound for controlling L. humile and can be used with minimal toxic effects on non-target organisms. The treatments cost approximately US$ 575/ha for the low-dose treatment and US$ 1250/ha for the high-dose treatment. Our research supports the creation of more ambitious invasive ant management projects.

Our goal was to create colonization and invasion risk maps for the Argentine ant, Linepithema humile, based on occurrence data in Japan, by combining colonization- and invasion-related variables and spatial filters that alleviate spatial autocorrelation. With these data, we will be better able to implement surveillance and control programs. Species distribution models were generated, using the maximum entropy approach, from presence-only data collected from 12 locations. Colonization-related variables (e.g., temperature, precipitation) and invasion-related variables (e.g., urban area, distance from ports) were used as environmental variables and spatial filters that alleviate spatial autocorrelation were included at the same time. The high invasion risk area was restricted to coastal areas, whereas high colonization risk applied to a broader area. Elevation, minimum temperature, and flow accumulation were the most effective variables for predicting colonization risk, whereas urban area, elevation, and the port distance index were the most effective variables for predicting invasion risk. The invasion risk map had a higher level of accuracy than the colonization risk map. We identified those areas with a high risk of invasion in the early stages and strong propagule pressure with a model using both invasion-related variables and colonization-related variables to accurately estimate the initial invasion distributions. We found that high colonization risk areas were concentrated in the Okinawa and Ogasawara Islands; ecosystems with highly endemic ant species that are likely to have a high sensitivity to L. humile introduction. Our data will aid in strengthening both domestic and international quarantine systems to prevent such introductions.

One of the major routes of transmission of rickettsial and ehrlichial diseases is via ticks that infest numerous host species, including humans. Besides mammals, reptiles and amphibians also carry ticks that may harbor Rickettsia and Ehrlichia strains that are pathogenic to humans. Furthermore, reptiles and amphibians are exempt from quarantine in Japan, thus facilitating the entry of parasites and pathogens to the country through import. Accordingly, in the current study, we examined the presence of Rickettsia and Ehrlichia spp. genes in ticks associated with reptiles and amphibians originating from outside Japan. Ninety-three ticks representing nine tick species (genera Amblyomma and Hyalomma) were isolated from at least 28 animals spanning 10 species and originating from 12 countries (Ghana, Jordan, Madagascar, Panama, Russia, Sri Lanka, Sudan, Suriname, Tanzania, Togo, Uzbekistan, and Zambia). None of the nine tick species are indigenous in Japan. The genes encoding the common rickettsial 17-kDa antigen, citrate synthase (gltA), and outer membrane protein A (ompA) were positively detected in 45.2% (42/93), 40.9% (38/93), and 23.7% (22/93) of the ticks, respectively, by polymerase chain reaction (PCR). The genes encoding ehrlichial heat shock protein (groEL) and major outer membrane protein (omp-1) were PCR-positive in 7.5% (7/93) and 2.2% (2/93) of the ticks, respectively. The p44 gene, which encodes the Anaplasma outer membrane protein, was not detected. Phylogenetic analysis showed that several of the rickettsial and ehrlichial sequences isolated in this study were highly similar to human pathogen genes, including agents not previously detected in Japan. These data demonstrate the global transportation of pathogenic Rickettsia and Ehrlichia through reptile- and amphibian-associated ticks. These imported animals have potential to transfer pathogens into human life. These results highlight the need to control the international transportation of known and potential pathogens carried by ticks in reptiles, amphibians, and other animals, in order to improve national and international public health.

2011年に中国で初めて確認された新たなダニ媒介性感染症である重症熱性血小板減少症候群（SFTS）が2013年1月に我が国でも確認された．死亡率が高く，根本的な治療法やワクチンがないことから大きな問題となっている．疫学や病態，保有マダニの種類や分布など自然界での存在様式についてもまだ不明な点が多いが，ここでは話題のSFTSについての概略ならびに現状とその対処法について述べた．

Recent molecular analyses of the Anaplasma sp. closely related to Anaplasma phagocytophilum (previously believed to be A. phagocytophilum) in Japan have clarified its distinct phylogenetic position. PCR methods relying on 16S rRNA- and P44/MSP2-based primers designed to detect this species have low sensitivity and specificity. In this study, a highly sensitive and specific nested PCR method using newly designed primers based on heat-shock operon gene (groEL) was developed to detect this species. The method was later used in an epidemiological study testing DNA samples from 85 Ixodid ticks (collected by flagging) and 50 cattle from the same pastureland in Nakaosobetsu, Hokkaido, Japan. Results revealed prevalence rates of 2.4% (2 of 85) in ticks and 2% (1 of 50) in cattle. The present study also reported the first molecular detection of the Anaplasma sp. closely related to A. phagocytophilum in Japan in H. douglasii, and established a new reliable PCR method that detects this Anaplasma sp. closely related to A. phagocytophilum in Japan.

We retrospectively confirmed 2 cases of human Anaplasma phagocytophilum infection. Patient blood samples contained unique p44/msp2 for the pathogen, and antibodies bound to A. phagocytophilum antigens propagated in THP-1 rather than HL60 cells. Unless both cell lines are used for serodiagnosis of rickettsiosis-like infections, cases of human granulocytic anaplasmosis could go undetected.

To the Editor: Japanese spotted fever (JSF), caused by Rickettsia japonica, is the most prevalent tickborne infectious disease in Japan (1), occurring most frequently in central and western regions (http://idsc.nih.go.jp/idwr/CDROM/Main.html [in Japanese]). Cases of unknown fever with rickettsiosis-like symptoms not associated with JSF have been reported in JSF-endemic regions of Japan (2). Several spotted fever group (SFG) rickettsiae (R. japonica, R. heilongjiangensis, R. helvetica, R. tamurae, R. asiatica, Candidatus R. tarasevichiae) and other related Rickettsia spp. have been identified in Japan (1,3–6). Human infections with R. heilongjiangensis and R. tamurae have been confirmed (3,5), and Anaplasma phagocytophilum and Ehrlichia chaffeensis, known human pathogens, have been detected in ticks and deer in Japan. We conducted this study to determine the risk in central and western Japan for human exposure to ticks harboring SFG rickettsiae, A. phagocytophilum, or Ehrlichia spp. In 2007–2011, we collected 827 Haemaphysalis, Amblyomma, and Ixodes spp. ticks (392 adults, 435 nymphs) by flagging vegetation in the prefectures of Shizuoka, Mie, Wakayama, Kagoshima, Nagasaki (Goto Island), and Okinawa (the main island and Yonaguni Island) (Technical Appendix Figure 1). We extracted DNA from the salivary glands of each tick and performed PCR to amplify gltA, 16S rDNA, and ompA of SFG rickettsiae. To detect A. phagocytophilum and Ehrlichia spp., we performed nested PCR targeting the p44/msp2 and p28/omp-1 multigenes, respectively. PCR gltA screening revealed SFG rickettsiae in 181 (21.9%) of the 827 ticks (Table). We obtained nearly full-length (1.1-kb) gltA sequences and classified them into 5 groups by phylogenetic analyses (Technical Appendix Figure 2). Sequences for groups 1 (prevalence 1.0%) and 2 (prevalence 3.2%) were identified as R. japonica YH (GenBank accession no. {"type":"entrez-nucleotide","attrs":{"text":"AP011533","term_id":"348592266","term_text":"AP011533"}}AP011533) and R. tamurae (GenBank accession no. {"type":"entrez-nucleotide","attrs":{"text":"AF394896","term_id":"21360604","term_text":"AF394896"}}AF394896), respectively (Table). Group 3 (prevalence 15.1%) sequences were identical to that of Rickettsia sp. LON (GenBank accession no. {"type":"entrez-nucleotide","attrs":{"text":"AB516964","term_id":"256353425","term_text":"AB516964"}}AB516964). The sequence for group 4 (prevalence 1.6%) was closely related to that for R. raoultii strain Khabarovsk (98.8% similarity), and a part of the sequence (342 bp) was identical to that of Rickettsia sp. Hf 151 (GenBank accession no. {"type":"entrez-nucleotide","attrs":{"text":"AB114815","term_id":"33146352","term_text":"AB114815"}}AB114815). Group 5 consisted of 4 newly identified rickettsiae (Technical Appendix Figure 2). Of these 4 rickettsiae, 3 (Mie311, Goto13, and Mie334) were closely related to R. raoultii strain Khabarovsk (98.0% identity) and 1 (Mie201) was similar to Candidatus R. principis (99.7% identity). Table PCR survey results for Haemaphysalis, Amblyomma, and Ixodes spp. ticks tested for rickettsiae, central and western Japan, 2007–2011* We further analyzed the 16S rDNA and ompA in gltA-positive tick samples. The 16S rDNA and ompA for group 1 samples shared 100% identity with 16S rDNA and ompA of R. japonica YH ({"type":"entrez-nucleotide","attrs":{"text":"AP011533","term_id":"348592266","term_text":"AP011533"}}AP011533). The 16S rDNA of group 2 was identical to that of R. tamurae ({"type":"entrez-nucleotide","attrs":{"text":"AY049981","term_id":"21360334","term_text":"AY049981"}}AY049981). In groups 3–5, some of the specific amplicons in 16S rDNA or ompA could be detected; their sequences were confirmed to be similar (but not identical) to those of several known rickettsial sequences. We amplified the p44/msp2 amplicons of A. phagocytophilum from 25 (3%) of 827 ticks (Table). By cloning (TA Cloning Kit; Life Technologies, Carlsbad, CA, USA) and sequencing these amplicons, we obtained and identified 60 new TA-clone sequences (366–507 bp) for p44/msp2 (GenBank accession nos. {"type":"entrez-nucleotide-range","attrs":{"text":"JQ697880-JQ697950","start_term":"JQ697880","end_term":"JQ697950","start_term_id":"383088493","end_term_id":"383088630"}}JQ697880-JQ697950); these sequences may include a potentially novel Anaplasma species. (7). Ehrlichia p28/omp-1 was detected from 2 (0.2%) of the 827 ticks. Of 5 TA-clone sequences (284–315 bp) obtained from the 2 ticks, 2 from an A. testudinarium tick (GenBank accession nos. {"type":"entrez-nucleotide","attrs":{"text":"JQ697886","term_id":"383088503","term_text":"JQ697886"}}JQ697886 and {"type":"entrez-nucleotide","attrs":{"text":"JQ697887","term_id":"383088505","term_text":"JQ697887"}}JQ697887) shared 83.3%–86.7% similarity with E. ruminantium Gardel Map-1 (GenBank accession no. YP196842), and 3 from an H. longicornis tick (GenBank accession nos. {"type":"entrez-nucleotide-range","attrs":{"text":"JQ697888-JQ697890","start_term":"JQ697888","end_term":"JQ697890","start_term_id":"383088507","end_term_id":"383088511"}}JQ697888-JQ697890) showed the closest relationship to E. ewingii omp-1–15 (67%–73% similarity; GenBank accession no. {"type":"entrez-nucleotide","attrs":{"text":"EF116932","term_id":"133711094","term_text":"EF116932"}}EF116932). We identified the tick species associated with R. japonica as H. formosensis, H. hystricis, and H. cornigera, and another study reported an association with Dermacentor taiwanensis, H. flava, H. longicornis, and I. ovatus (4). In our study and previous studies, the tick species associated with A. phagocytophilum in Japan were identified as H. formosensis, H. longicornis, H. megaspinosa, A. testudinarium, I. ovatus, and I. persulcatus (8). Thus, it appears that 3 tick species (H. formosensis, H. longicornis, and I. ovatus) are associated with R. japonica and A. phagocytophilum. In addition, in an H. formosensis tick, we detected an SFG rickettsia that is closely related to R. raoultii, the etiologic agent of Dermacentor-borne necrosis erythema and lymphadenopathy in Europe and Russia (9). We detected Candidatus R. principis in H. flava in Japan; this species was previously detected in H. japonica douglasi and H. danieli ticks in Russia and China, respectively, (10). And, we found a high prevalence of R. tamurae in A. testidinarium ticks; Imaoka et al. (5) recently reported that R. tamurae causes local skin inflammation without general JSP-like symptoms. We did not detect the human pathogen E. chaffeensis, but we identified 2 potentially new Ehrlichia species. Our findings contribute to the known risks for exposure to Rickettsia-related pathogens in central and western Japan. Further studies may be required for the surveillance of additional pathogens, such as Candidatus Neoehrlichia mikurensis (2), which was recently recognized as a human pathogen. Technical Appendix: Phylogenetic classification of Rickettsia spp. gltA sequences detected in ticks during 2007–2011 in central and western Japan and locations of tick collection sites. Click here to view.(154K, pdf)

During a survey of human rotaviruses in Okayama Prefecture, Japan in the 2011–2012 rotavirus season (between September 2011 and August 2012), G3P[8] was found to be a predominant genotype overall. However, G1P[8] emerged in the latter half of the season. To clarify the genetic background of the G1P[8] strains, the VP7, VP4, VP6, NSP4, and NSP5/6 genes of the strains were sequenced and genotyped. As a result, it was demonstrated that the strains with two different genotype constellations (G1‐P[8]‐I1‐E1‐H1 and G1‐P[8]‐I2‐E2‐H2) prevailed in the season. The G1P[8] strains possessing the DS‐1‐like VP6, NSP4, and NSP5/6 genes (the DS‐1‐like G1P[8] strains), which should reveal a short electropherotype, were originated from possible intergenogroup reassortment events. The DS‐1‐like G1P[8] strains accounted for 74.1% of all G1P[8] strains and were detected continuously throughout the season but not in the preceding season, indicating the possibility of new introduction and rapid spreading of these strains in the 2011–2012 season. The results suggest that the intergenogroup reassortants, considered generally unstable, can spread rapidly and become relevant. J. Med. Virol. 86:1056–1064, 2014. © 2013 Wiley Periodicals, Inc.

Rickettsia japonica is an obligate intracellular alphaproteobacteria that causes tick-borne Japanese spotted fever, which has spread throughout East Asia. We determined the complete genomic DNA sequence of R. japonica type strain YH (VR-1363), which consists of 1,283,087 base pairs (bp) and 971 protein-coding genes. Comparison of the genomic DNA sequence of R. japonica with other rickettsiae in the public databases showed that 2 regions (4,323 and 216 bp) were conserved in a very narrow range of Rickettsia species, and the shorter one was inserted in, and disrupted, a preexisting open reading frame (ORF). While it is unknown how the DNA sequences were acquired in R. japonica genomes, it may be a useful signature for the diagnosis of Rickettsia species. Instead of the species-specific inserted DNA sequences, rickettsial genomes contain Rickettsia-specific palindromic elements (RPEs), which are also capable of locating in preexisting ORFs. Precise alignments of protein and DNA sequences involving RPEs showed that when a gene contains an inserted DNA sequence, each rickettsial ortholog carried an inserted DNA sequence at the same locus. The sequence, ATGAC, was shown to be highly frequent and thus characteristic in certain RPEs (RPE-4, RPE-6, and RPE-7). This finding implies that RPE-4, RPE-6, and RPE-7 were derived from a common inserted DNA sequence.