Differential inducibility of transmembrane peptidoglycan recognition proteins (PGRPs) by bacterial challenges in the earthworm, Eisenia andrei.

Peptidoglycan recognition proteins (PGRPs) and Toll-like receptors (TLRs) are highly conserved pattern recognition receptors (PRRs). Earthworms possess genes encoding TLRs that specifically respond to Gram-positive bacteria. In addition, several PGRPs have been recently identified, which are predicted to exhibit amidase activity but lack receptor function.

Interaction-and-Response Network for Distantly Supervised Relation Extraction.

Distantly supervised relation extraction (DSRE) aims to identify semantic relations from massive plain texts. A broad range of the prior research has leveraged a series of selective attention mechanisms over sentences in a bag to extract relation features without considering dependencies among the relation features. As a result, potential discriminative information existed in the dependencies is ignored, causing a decline in the performance of extracting entity relations.

Slit-Robo expression in the leech nervous system: insights into eyespot evolution.

Background: Slit and Robo are evolutionarily conserved ligand and receptor proteins, respectively, but the number of slit and robo gene paralogs varies across recent bilaterian genomes. Previous studies indicate that this ligand-receptor complex is involved in axon guidance. Given the lack of data regarding Slit/Robo in the Lophotrochozoa compared to Ecdysozoa and Deuterostomia, the present study aims to identify and characterize the expression of Slit/Robo orthologs in leech development.

Peptidoglycan recognition proteins from the earthworm, Eisenia andrei: Differential inducibility and tissue-specific expression.

Several pattern recognition receptors (PRRs) involved in innate immunity have been identified and characterized in earthworms. Peptidoglycan recognition proteins (PGRPs) are highly conserved PRRs that activate effector pathways such as prophenoloxidase cascade and Toll-like receptor pathway. In addition, PGRPs function as an enzyme, N-acetylmuramoyl-l-alanine amidase (NAMLAA), to directly hydrolyze peptidoglycan.

Head transcriptome profiling of glossiphoniid leech () reveals clues about proboscis development.

Cephalization refers to the evolutionary trend towards the concentration of neural tissues, sensory organs, mouth and associated structures at the front end of bilaterian animals. Comprehensive studies on gene expression related to the anterior formation in invertebrate models are currently lacking. In this study, we performed transcriptional profiling on a proboscis-bearing leech () to identify differentially expressed genes (DEGs) in the anterior versus other parts of the body, in particular to find clues as to the development of the proboscis.

Transcriptional upregulation of multiple earthworm chitinase genes following bacterial challenge suggests their implications in innate immunity.

Background: Chitinase is a multi-functional enzyme that catalyzes the hydrolysis of β-1,4-linkages between N-acetylglucosamines (GlcNAc) in chitin. Recent studies imply that earthworm chitinase is implicated in self-defense immunity against chitin-containing pathogens. However, a direct relationship of earthworm chitinase with innate immunity has not yet been established.

Behavioral variation according to feeding organ diversification in glossiphoniid leeches (Phylum: Annelida).

Adaptive radiation is a phenomenon in which various organs are diversified morphologically or functionally as animals adapt to environmental inputs. Leeches exhibit a variety of ingestion behaviors and morphologically diverse ingestion organs. In this study, we investigated the correlation between behavioral pattern and feeding organ structure of leech species.

Identification and expression of adenosine deaminases acting on tRNA (ADAT) during early tail regeneration of the earthworm.

Background: RNA editing is a widespread phenomenon in all metazoans. One of the common RNA editing event is the chemical conversion of adenosine to inosine (A-to-I) catalyzed by adenosine deaminases acting on tRNA (ADAT). During D.

Identification and Spatiotemporal Expression of Adenosine Deaminases Acting on RNA (ADAR) during Earthworm Regeneration: Its Possible Implication in Muscle Redifferentiation.

Adenosine deaminases acting on RNA (ADAR) catalyze the hydrolytic deamination of adenosine (A) to produce inosine (I) in double-stranded RNA substrates. A-to-I RNA editing has increasingly broad physiological significance in development, carcinogenesis, and environmental adaptation. is an earthworm with potent regenerative potential; it can regenerate the head and tail and is an advantageous model system to investigate the molecular mechanisms of regeneration.

Characterization of Development and Its Head Regeneration.

Regeneration is a biological process restoring lost or amputated body parts. The capability of regeneration varies among organisms and the regeneration of the central nervous system (CNS) is limited to specific animals, including the earthworm . Thus, it is crucial to establish as a model system to investigate mechanisms of CNS regeneration.

Upregulation of cellulase activity and mRNA levels by bacterial challenge in the earthworm Eisenia andrei, supporting the involvement of cellulases in innate immunity.

To investigate whether earthworm cellulases contribute to the innate immune system, the responsiveness of cellulase activity and mRNA expression to bacterial challenge was examined by zymography and RNA sequencing. A zymographic analysis revealed that the activity levels of earthworm cellulases were upregulated in response to either a bacterial (Bacillus subtilis or Escherichia coli) or LPS challenge. After the challenge, significant increases in cellulase 1 and cellulase 2 activity levels were observed within 8-16 and 16-24 h, respectively.

Spatiotemporal Expression of Anticoagulation Factor in Freshwater Leeches.

, which was originally discovered in the salivary glands of the Mexican leech , was newly isolated from . To confirm the temporal expression of during embryogenesis, we carried out semi-quantitative RT-PCR. was uniquely expressed at stage 4 of the cleavage and was strongly expressed in the late stages of organogenesis, as were other members.

Identification and expression pattern of a new digestive invertebrate-type lysozyme from the earthworm.

Background: The invertebrate type (i-type) lysozyme not showing a clear homology with the known types of lysozyme was first demonstrated from a marine bivalve, conch and earthworm by N-terminal sequence. An i-type lysozyme isolated from the earthworm found to be up-regulated upon bacterial challenge, suggesting this lysozyme to function as an inducible immune factor. However, information on the i-type lysozyme related with digestive function is very limited in the earthworm.

Temporal and spatial expression of the Fox gene family in the Leech Helobdella austinensis.

The Forkhead box (Fox) gene family is an evolutionarily ancient gene family named after the Drosophila melanogaster forkhead gene (fkh). Fox genes are highly conserved transcription factors critical for embryogenesis and carcinogenesis. In the current study, we report a whole-genome survey of Fox genes and their expression patterns in the leech Helobdella austienesis.

Expression patterns of duplicated snail genes in the leech Helobdella.

snail gene family members are zinc-finger transcription factors with key roles in morphogenesis. Involvement of snail family genes in mesoderm formation has been observed in insects and mammals. The snail genes are also involved in cell motility, neural differentiation, cell fate, survival decision, and left-right identity.

Spatiotemporal expression of a twist homolog in the leech Helobdella austinensis.

Genes of the twist family encode bHLH transcription factors known to be involved in the regulation and differentiation of early mesoderm. Here, we report our characterization of Hau-twist, a twist homolog from the leech Helobdella austinensis, a tractable lophotrochozoan representative. Hau-twist was expressed in segmental founder cells of the mesodermal lineage, in subsets of cells within the mesodermal lineage of the germinal plate, in circumferential muscle fibers of a provisional integument during segmentation and organogenesis stages and on the ventral side of the developing proboscis.

A new earthworm cellulase and its possible role in the innate immunity.

A new endogenous cellulase (Ean-EG) from the earthworm, Eisenia andrei and its expression pattern are demonstrated. Based on a deduced amino acid sequence, the open reading frame (ORF) of Ean-EG consisted of 1368 bps corresponding to a polypeptide of 456 amino acid residues in which is contained the conserved region specific to GHF9 that has the essential amino acid residues for enzyme activity. In multiple alignments and phylogenetic analysis, the deduced amino acid sequence of Ean- EG showed the highest sequence similarity (about 79%) to that of an annelid (Pheretima hilgendorfi) and could be clustered together with other GHF9 cellulases, indicating that Ean-EG could be categorized as a member of the GHF9 to which most animal cellulases belong.

Long noncoding RNA linc00598 regulates CCND2 transcription and modulates the G1 checkpoint.

Data derived from genomic and transcriptomic analyses have revealed that long noncoding RNAs (lncRNAs) have important roles in the transcriptional regulation of various genes. Recent studies have identified the mechanism underlying this function. To date, a variety of noncoding transcripts have been reported to function in conjunction with epigenetic regulator proteins.

Gene expression profiling of coelomic cells and discovery of immune-related genes in the earthworm, Eisenia andrei, using expressed sequence tags.

The coelomic cells of the earthworm consist of leukocytes, chlorogocytes, and coelomocytes, which play an important role in innate immunity reactions. To gain insight into the expression profiles of coelomic cells of the earthworm, Eisenia andrei, we analyzed 1151 expressed sequence tags (ESTs) derived from the cDNA library of the coelomic cells. Among the 1151 ESTs analyzed, 493 ESTs (42.

Additional duplicated Hox genes in the earthworm: Perionyx excavatus Hox genes consist of eleven paralog groups.

Annelida is a lophotrochozoan phylum whose members have a high degree of diversity in body plan morphology, reproductive strategies and ecological niches among others. Of the two traditional classes pertaining to the phylum Annelida (Polychaete and Clitellata), the structure and function of the Hox genes has not been clearly defined within the Oligochaeta class. Using a PCR-based survey, we were able to identify five new Hox genes from the earthworm Perionyx excavatus: a Hox3 gene (Pex-Hox3b), two Dfd genes (Pex-Lox6 and Pex-Lox18), and two posterior genes (Pex-post1 and -post2a).

The morphology of the rat vibrissal follicle-sinus complex revealed by three-dimensional computer-aided reconstruction.

The vibrissal follicle-sinus complex (FSC) is a sensory receptor of the mammalian integumentary system that is located around the mouth. The purpose of the present study was to identify the actual 3-dimensional structure of the rat vibrissal FSC. Rat skin tissue was serially sectioned at a thickness of 10 μm and then stained with Masson's trichrome.

Differential expression of three labial genes during earthworm head regeneration.

The earthworm provides an excellent model for investigating regeneration. Here we report the full-length cloning of three labial genes (Pex-lab01, Pex-lab02, and Pex-lab03) in the earthworm Perionyx excavatus. To analyze their expression pattern during head and tail regeneration, we used the reverse transcription-polymerase chain reaction.