Extended spectrum and metalo beta lactamase producing gram negative bacterial pathogens from cockroaches collected at hospital, Southern Ethiopia.

BACKGROUND: Cockroaches can pose a significant health risk in hospital environments because they may serve as reservoirs and vectors for nosocomial pathogens. Cockroaches harbor epidemiologically significant extended spectrum and metalo beta lactamase producing Gram negative bacterial pathogens, which complicate nosocomial infections. OBJECTIVES: The main aim of this study is to determine aetiology and phenotypic extended spectrum and metalo beta lactamase producing Gram negative bacteria pathogens from cockroaches collected in hospitals. METHODS: A cross-sectional study was employed from February to May 2022 to determine the antibiotic resistance producing bacterial isolates from cockroaches by giving special emphasis to metalo beta lactamase and extended spectrum beta lactamase production from different wards of WSUCSH. Cockroaches were collected with hands wearing sterile gloves. External homogenate was prepared and incubated microbiologically by using different culture media and differentiated biochemically. Antimicrobial susceptibility testing was performed by disk diffusion method. ESBL production was conducted using double disc synergy method and double disk method was used to detect MBL enzyme detection. Descriptive statistics was used to determine prevalence and percentage. RESULT: Out of 245 cockroaches, 108 Gram negative bacteria were isolated. K. pneumoniae 29(26.9%) was the most predominant bacteria and Enetrobacter spp. 8(7.4%), was the least. All, K. pneumoniae, P. mirabilis, and Enterobacter isolates were pan-resistant to Ampicillin. P.aeruginosa and P.mirabilis antibiotics showed ≥ 80% resistant for amoxicillin/clavulanic acid antibiotics. Cefotaxime, ceftazidime, ceftriaxone and imipenem showed relative efficacy compared with other antibiotics. Out of 78 amoxicillin-clavulanic acid resistant isolates, 42(34.7%) were ESBL producers. ESBL production is more depicted by P. aeruginosa, A. baumannii, K. pneumoniae and E. coli. The overall prevalence of MBL production is 29(23.1%). K. pneumoniae P. aeruginosa, E.coli, A. baumannii, Enterobacter spp and K.oxytoca revealed MBL production. CONCLUSION: The overall prevalence of ESBL and MBL producing nosocomial agents from hospital cockroaches was 34.7% and 23.1% respectively. P.aeruginosa, A.baumannii, K.pneumoniae and E.coli showed pronounced ESBL production. All bacterial isolates except P. mirabilis and C. freundii showed MBL production. The needed to evaluate our antibiotic stewardship program and antibiotic resistance detection for treatment is mandatory. The impact of cockroach as a source of AMR should be sought.

[From exposure to control: the application of allergen component-resolved diagnosis in the clinical management of cockroach allergies].

Cockroaches are one of the most common indoor allergens worldwide, and exposure to cockroach allergens (such as the insect body, debris, and secretions) can trigger severe allergic rhinitis and(or) asthma. Currently, the World Health Organization (WHO)/International Union of Immunological Societies (IUIS) has identified 32 allergenic components in cockroaches, but none of these allergens have shown a clear immunodominance. The sensitization rate to cockroach allergens shows significant variability across different regions and populations and exhibits cross-reactivity with various invertebrates, increasing the complexity of clinical diagnosis and treatment. This article delves into the "Molecular Allergology User's Guide 2.0"(MAUG 2.0) published by the European Academy of Allergy and Clinical Immunology (EAACI) and the research progress on cockroach allergies both domestically and internationally. It elucidates the crucial role of allergen component diagnostic technology in enhancing the diagnosis and treatment of cockroach-induced allergic diseases, efficiently assisting clinicians in identifying common sensitizations and cross-reactivities, thereby offering patients more accurate diagnoses and personalized treatment plans.

The hidden RNA viruses in Blattodea (cockroaches and termites).

The insect order Blattodea (cockroaches and termites) has drawn substantial research attention for their dietary habits and lifestyle of living with or around humans. In the present study, we focused on the discovery of RNA viruses hidden in Blattodea insects using the publicly available RNA sequencing datasets. Overall, 136 distinctive RNA viruses were identified from 36 Blattodea species, of which more than 70 % were most closely related to the invertebrate-associated viral groups within Picornavirales, Sobelivirales, Bunyaviricetes, Jingchuvirales, Durnavirales, Lispiviridae, Orthomyxoviridae, Permutotetraviridae, Flaviviridae and Muvirales. Several viruses were associated with pathogens of vertebrates (Paramyxoviridae), plants (Tymovirales), protozoa (Totiviridae), fungi (Narnaviridae) and bacteria (Norzivirales). Collectively, 93 complete or near-complete viral genomes were retrieved from the datasets, and several viruses appeared to have remarkable temporal and spatial distributions. Interestingly, the newly identified Periplaneta americana dicistrovirus displayed a remarkable distinct bicistronic genome arrangement from the well-recognized dicistroviruses with the translocated structural and non-structural polyprotein encoding open reading frames over the genome. These results significantly enhance our knowledge of RNA virosphere in Blattodea insects, and the novel genome architectures in dicistroviruses and other RNA viruses may break our stereotypes in the understanding of the genomic evolution and the emergence of potential novel viral species.

Functional redundancy of the three insulin receptors of cockroaches.

Gene duplication is a fundamental evolutionary process which provides opportunities to acquire new gene functions. In the case of the insulin receptors (InRs) in cockroaches and close-related insects, two successive duplications determined the occurrence of three InR genes: InR2, InR1 and InR3, the last two forming a sister cluster to InR2. The biological role of each of the gene duplicates and whether they resulted from neofunctionalization or subfunctionalization is still unclear. The analysis of the sequences from different lineages did not detect positive selection as driving the divergence of InR1 and InR3, discarding neofunctionalization, and suggesting that there is no functional divergence between both gene copies. Using the cockroach Blattella germanica as a model, we have determined that BgInR2 is the gene with the highest expression levels in all the tissues analyzed, both in adult females and males, as well as in nymphs and embryos. BgInR3 is second in expression levels while BgInR1 is expressed at lower levels and only in some tissues. The selective depletion by RNAi of each of the three InRs, analyzed in terms of phenotype and fat body transcriptomic profiles, resulted in essentially redundant effects, with a magnitude approximately proportional to the level of expression of the respective InR. Therefore, the results indicate that the InR duplicates likely experienced a subfunctionalization process, by which the three InRs maintained similar functions but contributing to those functions proportionally to their expression levels.

Molecular analyses of the Kalotermes dispar-complex (Blattodea: Kalotermitidae) from the Canary Islands reveal cryptic intraspecific divergence and a connection to a lone Nearctic congener.

The Canary Islands is a Macaronesian volcanic archipelago with a depauperate community of three species of Kalotermitidae, including Kalotermes dispar. A total of 54 Kalotermes colonies were collected from Gran Canaria, Tenerife, La Gomera, La Palma, and El Hierro islands. Soldiers and imagos were morphologically examined and sequenced for four mitochondrial markers. Although morphological differences could not be detected, phylogenetic analysis of both cox1/tRNA/cox2 and rrnL markers revealed two distinct clades of K. dispar, suggesting cryptic diversity. The diversification within the Canary Kalotermes lineage most likely occurred around 7.5 Mya, while the divergence within the two clades was reconstructed at about 3.6 Mya and 1.9 Mya. Kalotermes approximatus from the southeastern Nearctic constitutes a sister to the Canary Kalotermes, while the Palearctic K. flavicollis, K. italicus, and K. phoenicae form a separate clade. It is hypothesized that a faunal exchange of Kalotermes from the Nearctic to the Canary Islands occurred via transoceanic rafting during the mid-Miocene.

Pathogenic fungi synergistically cooperate with Serratia marcescens to increase cockroach mortality.

The abuse of chemical insecticides has led to strong resistance in cockroaches, and biopesticides with active ingredients based on insect pathogens have good development prospects; however, their slow effect has limited their practical application, and improving their effectiveness has become an urgent problem. In this study, the interaction between Serratia marcescens and Metarhizium anisopliae enhanced their virulence against Blattella germanica and exhibited a synergistic effect. The combination of S. marcescens and M. anisopliae caused more severe tissue damage and accelerated the proliferation of the insect pathogen. The results of high-throughput sequencing demonstrated that the gut microbiota was dysbiotic, the abundance of the opportunistic pathogen Weissella cibaria increased, and entry into the hemocoel accelerated the death of the German cockroaches. In addition, the combination of these two agents strongly downregulated the expression of Imd and Akirin in the IMD pathway and ultimately inhibited the expression of antimicrobial peptides (AMPs). S. marcescens released prodigiosin to disrupted the gut homeostasis and structure, M. anisopliae released destruxin to damaged crucial organs, opportunistic pathogen Weissella cibaria overproliferated, broke the gut epithelium and entered the hemocoel, leading to the death of pests. These findings will allow us to optimize the use of insect pathogens for the management of pests and produce more effective biopesticides.

Production and Release of Proinflammatory Mediators by the Cockroach Allergen Bla g 1 via a Shared Membrane-Destabilization Mechanism.

The cockroach allergen Bla g 1 encloses an exceptionally large hydrophobic cavity, which allows it to bind and deliver unsaturated fatty acid ligands. Bla g 1-mediated delivery of naturally occurring (nMix) ligands has been shown to destabilize lipid membranes, contributing to its digestive/antiviral functions within the source organism. However, the consequences of this activity on Bla g 1 allergenicity following human exposure remain unknown. In this work, we show that Bla g 1-mediated membrane disruption can induce a proinflammatory immune response in mammalian cells via two complementary pathways. At high concentrations, the cytotoxic activity of Bla g 1 induces the release of proinflammatory cytosolic contents including damage-associated molecular patterns (DAMPs) such as heat-shock Protein-70 (HSP70) and the cytokine interleukin-1 (IL-1ß). Sublytic concentrations of Bla g 1 enhanced the ability of phospholipase A2 (PLA2) to extract and hydrolyze phospholipid substrates from cellular membranes, stimulating the production of free polyunsaturated fatty acids (PUFAs) and various downstream inflammatory lipid mediators. Both of these effects are dependent on the presence of Bla g 1's natural fatty-acid (nMix) ligands with CC50 values corresponding to the concentrations required for membrane destabilization reported in previous studies. Taken together, these results suggest that mechanisms through which Bla g 1-mediated lipid delivery and membrane destabilization could directly contribute to cockroach allergic sensitization.

A Novel Peptidomimetic Insecticide: Dippu-AstR-Based Rational Design and Biological Activity of Allatostatin Analogs.

Insect neuropeptides play an essential role in regulating growth, development, reproduction, nerve conduction, metabolism, and behavior in insects; therefore, G protein-coupled receptors of neuropeptides are considered important targets for designing green insecticides. Cockroach-type allatostatins (ASTs) (FGLamides allatostatins) are important insect neuropeptides in Diploptera punctata that inhibit juvenile hormone (JH) synthesis in the corpora allata and affect growth, development, and reproduction of insects. Therefore, the pursuit of novel insecticides targeting the allatostatin receptor (AstR) holds significant importance. Previously, we identified an AST analogue, H17, as a promising candidate for pest control. Herein, we first modeled the 3D structure of AstR in D. punctata (Dippu-AstR) and predicted the binding mode of H17 with Dippu-AstR to study the critical interactions and residues favorable to its bioactivity. Based on this binding mode, we designed and synthesized a series of H17 derivatives and assessed their insecticidal activity against D. punctata. Among them, compound Q6 showed higher insecticidal activity than H17 against D. punctata by inhibiting JH biosynthesis, indicating that Q6 is a potential candidate for a novel insect growth regulator (IGR)-based insecticide. Moreover, Q6 exhibited insecticidal activity against Plutella xylostella, indicating that these AST analogs may have a wider insecticidal spectrum. The underlying mechanisms and molecular conformations mediating the interactions of Q6 with Dippu-AstR were explored to understand its effects on the bioactivity. The present work clarifies how a target-based strategy facilitates the discovery of new peptide mimics with better bioactivity, enabling improved IGR-based insecticide potency in sustainable agriculture.

Pervasive relaxed selection in termite genomes.

Genetic changes that enabled the evolution of eusociality have long captivated biologists. More recently, attention has focussed on the consequences of eusociality on genome evolution. Studies have reported higher molecular evolutionary rates in eusocial hymenopteran insects compared with their solitary relatives. To investigate the genomic consequences of eusociality in termites, we analysed nine genomes, including newly sequenced genomes from three non-eusocial cockroaches. Using a phylogenomic approach, we found that termite genomes have experienced lower rates of synonymous substitutions than those of cockroaches, possibly as a result of longer generation times. We identified higher rates of non-synonymous substitutions in termite genomes than in cockroach genomes, and identified pervasive relaxed selection in the former (24-31% of the genes analysed) compared with the latter (2-4%). We infer that this is due to reductions in effective population size, rather than gene-specific effects (e.g. indirect selection of caste-biased genes). We found no obvious signature of increased genetic load in termites, and postulate efficient purging of deleterious alleles at the colony level. Additionally, we identified genomic adaptations that may underpin caste differentiation, such as genes involved in post-translational modifications. Our results provide insights into the evolution of termites and the genomic consequences of eusociality more broadly.

Reductitherus cryptostomus n. gen., n. sp. (Ciliophora: Armophorea: Clevelandellida), a remarkable new nyctotherid from an Australian cockroach, Parapanesthia gigantea (Blaberidae: Panesthiinae).

Ciliates of the family Nyctotheridae (Armophorea: Clevelandellida) are frequent intestinal symbionts of various invertebrates and some poikilotherm vertebrates. Depending on the classification scheme, there are between 15 and 18 recognized genera of Nyctotheridae, the majority of which exhibit a rather uniform morphology. They have round to ellipsoidal cells with an adoral zone of membranelles that begins anteriorly in an adoral groove and continues posteriorly into the buccal cavity where it extends deep into the cell in the peristomial funnel. The taxonomy of the Nyctotheridae is primarily based on the number and location of kinetal sutures. The only known divergence from the relatively conservative nyctortherid body plan are the bizarre symbionts of Panesthiinae cockroaches, ciliates of the family Clevelandellidae, which forms a clade nested within the Nyctotheridae genus Nyctotherus. In this study we report another ciliate that diverges morphologically from the canonical Nyctotheridae body plan, and which is also found in Panesthiinae hosts. The novel ciliate Reductitherus cryptostomus n. gen., n. sp. differs from the rest of Nyctotheridae by absence of the anterior adoral groove, a shortened adoral zone completely enclosed in a notably small buccal cavity, and two strongly reduced kinetal sutures, one left anterodorsal and the other right posterodorsal.

Pinworm Blatticola blattae infection and survival of starving German cockroach Blattella germanica.

The German cockroach Blattella germanica is commonly infected with the pinworm Blatticola blattae. To determine the effect of pinworm infection on cockroach survival, we artificially altered the pinworm infection status of cockroaches and determined the number of survival days under no-feeding conditions, with and without opportunities for fecal feeding. Four lines of the German cockroach (Wn, Wp, Nn, and Np groups) were used in the experiment. Wp and Np were pinworm-infected lines. Wn and Nn were pinworm-free lines. The 50% survival days of cockroaches in the absence of opportunities for fecal feeding were not significantly different in Wp (3.45 days) vs Wn (3.27), and in Np (4.60) vs Nn (4.48). In contrast, in the presence of fecal feeding, the 50% survival times for the pinworm-infected Wp (4.04) and Np (6.65) were significantly longer than those for the pinworm-free Wn (2.77) and Nn (5.46). The number of survival days without feeding was significantly higher in the pinworm-infected group given the opportunity to eat feces than in the non-infected group. These results suggest that pinworm infection of cockroaches during starvation, in association with fecal feeding, may be associated with longer survival.

The destructive subterranean termite Reticulitermes flavipes (Blattodea: Rhinotermitidae) can colonize arid territories.

Reticulitermes flavipes, one of the most destructive subterranean termite species, has been detected for the first time in an arid territory: Lanzarote (Canary Islands, Spain). This invasive species was introduced into several countries but never such a dry region. Although there are places with presence of this termite at similar or even higher temperatures, none has annual rainfall (10.1 mm) as low as Lanzarote. On this island it is present in semi-desert, near an affected urban area. Distribution, genetic, climate and host-plant data are evaluated to track and understand its invasion process in the archipelago.

A comprehensive sampling of mitogenomes shows the utility to infer phylogeny of termites (Blattodea: Termitoidae).

The mitogenome sequence data have been widely used in inferring the phylogeny of insects. In this study, we determined the complete mitogenome for Macrotermes sp. (Termitidae, Macrotermitinae) using next-generation sequencing. Macrotermes sp. possesses a typical insect mitogenome, displaying an identical gene order and gene content to other existing termite mitogenomes. We present the first prediction of the secondary structure of ribosomal RNA genes in termites. The rRNA secondary structures of Macrotermes sp. exhibit similarities to closely related insects and also feature distinctive characteristics in their helical structures. Together with 321 published mitogenomes of termites as ingroups and 8 cockroach mitogenomes as outgroups, we compiled the most comprehensive mitogenome sequence matrix for Termitoidae to date. Phylogenetic analyses were conducted using datasets employing different data coding strategies and various inference methods. Robust relationships were recovered at the family or subfamily level, demonstrating the utility of comprehensive mitogenome sampling in resolving termite phylogenies. The results supported the monophyly of Termitoidae, and consistent relationships within this group were observed across different analyses. Mastotermitidae was consistently recovered as the sister group to all other termite families. The families Hodotermitidae, Stolotermitidae, and Archotermopsidae formed the second diverging clade, followed by the Kalotermitidae. The Neoisoptera was consistently supported with strong node support, with Stylotermitidae being sister to the remaining families. Rhinotermitidae was found to be non-monophyletic, and Serritermitidae nested within the basal clades of Rhinotermitidae and was sister to Psammotermitinae. Overall, our phylogenetic results are largely consistent with earlier mitogenome studies.

Defensive glands in Stylotermitidae (Blattodea, Isoptera).

The large abundance of termites is partially achieved by their defensive abilities. Stylotermitidae represented by a single extant genus, Stylotermes, is a member of a termite group Neoisoptera that encompasses 83% of termite species and 94% of termite genera and is characterized by the presence of the frontal gland. Within Neoisoptera, Stylotermitidae represents a species-poor sister lineage of all other groups. We studied the structure of the frontal, labral and labial glands in soldiers and workers of Stylotermes faveolus, and the composition of the frontal gland secretion in S. faveolus and Stylotermes halumicus. We show that the frontal gland is a small active secretory organ in soldiers and workers. It produces a cocktail of monoterpenes in soldiers, and some of these monoterpenes and unidentified proteins in workers. The labral and labial glands are developed similarly to other termite species and contribute to defensive activities (labral in both castes, labial in soldiers) or to the production of digestive enzymes (labial in workers). Our results support the importance of the frontal gland in the evolution of Neoisoptera. Toxic, irritating and detectable monoterpenes play defensive and pheromonal functions and are likely critical novelties contributing to the ecological success of these termites.

Anatomical organization of the cerebrum of the praying mantis Hierodula membranacea.

Many predatory animals, such as the praying mantis, use vision for prey detection and capture. Mantises are known in particular for their capability to estimate distances to prey by stereoscopic vision. While the initial visual processing centers have been extensively documented, we lack knowledge on the architecture of central brain regions, pivotal for sensory motor transformation and higher brain functions. To close this gap, we provide a three-dimensional (3D) reconstruction of the central brain of the Asian mantis, Hierodula membranacea. The atlas facilitates in-depth analysis of neuron ramification regions and aides in elucidating potential neuronal pathways. We integrated seven 3D-reconstructed visual interneurons into the atlas. In total, 42 distinct neuropils of the cerebrum were reconstructed based on synapsin-immunolabeled whole-mount brains. Backfills from the antenna and maxillary palps, as well as immunolabeling of γ-aminobutyric acid (GABA) and tyrosine hydroxylase (TH), further substantiate the identification and boundaries of brain areas. The composition and internal organization of the neuropils were compared to the anatomical organization of the brain of the fruit fly (Drosophila melanogaster) and the two available brain atlases of Polyneoptera-the desert locust (Schistocerca gregaria) and the Madeira cockroach (Rhyparobia maderae). This study paves the way for detailed analyses of neuronal circuitry and promotes cross-species brain comparisons. We discuss differences in brain organization between holometabolous and polyneopteran insects. Identification of ramification sites of the visual neurons integrated into the atlas supports previous claims about homologous structures in the optic lobes of flies and mantises.

A Taxonomic Revision of the South American Trilobite Cockroaches of Parahormetica Brunner von Wattenwyl 1865 (Blattodea: Blaberidae), with Description of Parahormetica museunacional sp. nov. from the Atlantic Forest.

The taxonomically intricate genus of trilobite cockroaches, Parahormetica Brunner von Wattenwyl, 1865, is revised based on a comparative morphological analysis. The goals of this study are to review the nomenclature, propose hypotheses about specific delimitation, and provide diagnoses to allow identification of the taxonomic units in the genus. Based on the revised status of Parahormetica, we transferred Parahormetica hylaeceps Miranda-Ribeiro, 1936, and Parahormetica punctata Saussure, 1873, to the genus Bionoblatta Rehn, 1940. Therefore, the genus includes now four species of giant cockroaches which are predominantly distributed on the Atlantic Forest: Parahormetica bilobata (Saussure, 1864), Parahormetica cicatricosa Saussure, 1869, Parahormetica monticollis (Burmeister, 1838), and Parahormetica museunacional sp. nov. (holotype male deposited in DZUP: Brazil, Paraná). Diagnoses, key, distribution maps, images of living, non-type, and type specimens are made available. Our results make clear that the status and limits among Brachycolini genera pending a full revision.

Conspecific and heterospecific cueing in shelter choices of Blaptica dubia cockroaches.

Background: Like many cockroaches, Argentinian wood roaches, Blaptica dubia, prefer darker shelters over lighter shelters. In three experiments, we asked whether chemical cues from other roaches might influence shelter choice, a process known as conspecific or heterospecific cueing, depending on whether the cues come from an individual of the same or a different species, respectively. Methods: Each experiment involved trials with focal B. dubia cockroaches in testing arenas containing plastic shelters of varying levels of darkness, with filter paper under each shelter acting as a carrier for chemical cues. In Experiment 1, we tested female and male B. dubia cockroaches with two shelters matched for darkness but differing in cues (conspecific vs. none). The shelter with no cue contained a blank filter paper as a control. In Experiment 2 (conspecific cueing) and Experiment 3 (heterospecific cueing), we tested B. dubia cockroach choices for lighter or darker shelters with filter papers containing chemical cues of other roaches or no chemical cues. For the conspecific cueing study of Experiment 2, we used chemical cues from other B. dubia cockroaches. In contrast, for the heterospecific cueing study of Experiment 3, we used chemical cues from a different species, the death's head cockroach, Blaberus craniifer. Results: In Experiment 1, B. dubia cockroaches overwhelmingly preferred shelters with conspecific chemical cues over darkness-matched shelters without cues. In Experiments 2 and 3, they strongly preferred darker shelters, especially when chemical cues were present. Additionally, they were more likely to be under the lighter shelter when chemical cues were present there. These results reveal that the public information B. dubia cockroaches gain from chemical cues-including those from other species-can drive shelter choices in this species.

Cockroaches as carriers of human medically important parasites.

Cockroaches have been identified as mechanical carriers of pathogens capable of infesting humans. The primary objective of this research was to detect and separate medically significant parasites found within the collected cockroaches. A total of 185 cockroaches were captured. In the laboratory, cockroaches underwent a series of steps. Initially, they were washed in a saturated salt solution and rinsed with 70% alcohol, dried, and subsequently dissected to examine endoparasites. In this study, a transport rate of 29.729% was documented, and four types of helminths were identified, which included Ascaris lumbricoides (47.27%), Enterobius vermicularis (30.91%), Trichuris spp. (7.27%), and Hymenolepis nana (14.55%). The parasites were more frequently found on the external surface of cockroaches (38/69.09%), compared to the internal surface (17/30.91%). Cockroaches captured in toilets were found to carry a higher percentage of parasites (31/16.75%) compared to those from kitchens (11/5.94%) and houses (13/7.02%). These findings suggest that cockroaches can serve as carriers for intestinal parasites and potentially act as mechanical agents in the dissemination of these parasites.

Two transcriptional cascades orchestrate cockroach leg regeneration.

The mystery of appendage regeneration has fascinated humans for centuries, while the underlying regulatory mechanisms remain unclear. In this study, we establish a transcriptional landscape of regenerating leg in the American cockroach, Periplaneta americana, an ideal model in appendage regeneration studies showing remarkable regeneration capacity. Through a large-scale in vivo screening, we identify multiple signaling pathways and transcription factors controlling leg regeneration. Specifically, zfh-2 and bowl contribute to blastema cell proliferation and morphogenesis in two transcriptional cascades: bone morphogenetic protein (BMP)/JAK-STAT-zfh-2-B-H2 and Notch-drm/bowl-bab1. Notably, we find zfh-2 is working as a direct target of BMP signaling to promote cell proliferation in the blastema. These mechanisms might be conserved in the appendage regeneration of vertebrates from an evolutionary perspective. Overall, our findings reveal that two crucial transcriptional cascades orchestrate distinct cockroach leg regeneration processes, significantly advancing the comprehension of molecular mechanism in appendage regeneration.