MRLC controls apoptotic cell death and functions to regulate epidermal development during planarian regeneration and homeostasis.

Adult stem cells (ASCs) are pluripotent cells with the capacity to self-renew and constantly replace lost cells due to physiological turnover or injury. Understanding the molecular mechanisms of the precise coordination of stem cell proliferation and proper cell fate decision is important to regeneration and organismal homeostasis. The planarian epidermis provides a highly tractable model to study ASC complex dynamic due to the distinct spatiotemporal differentiation stages during lineage development.

Meis1 Controls the Differentiation of Eye Progenitor Cells and the Formation of Posterior Poles during Planarian Regeneration.

As a member of TALE family, Meis1 has been proven to regulate cell proliferation and differentiation during cell fate commitment; however, the mechanism is still not fully understood. The planarian, which has an abundance of stem cells (neoblasts) responsible for regenerating any organ after injury, is an ideal model for studying the mechanisms of tissue identity determination. Here, we characterized a planarian homolog of Meis1 from the planarian .

Is Required for Proper Regeneration and Maintenance of the Medial Tissues in Planarians.

CK1α (Casein kinase 1α) is a member of the casein kinase 1(CK1) family that is involved in diverse cellular processes, but its functions remain unclear in stem cell development. Freshwater planarians are capable of whole-body regeneration, making it a classic model for the study of regeneration, tissue homeostasis, and polarity in vivo. To investigate the roles of CK1α in regeneration and homeostasis progress, we characterize a homolog of CK1α from planarian .

Djsnon, a downstream gene of Djfoxk1, is required for the regeneration of the planarian central nervous system.

Regulators of adult neurogenesis are crucial targets for neuronal repair. Freshwater planarians are ideal model systems for studying neuronal regeneration as they can regenerate their entire central nervous system (CNS) using pluripotent adult stem cells. Here, we identified Djfoxk1 in planarian Dugesia japonica to be required for planarian CNS regeneration.

Actin restricts cell proliferation and promotes differentiation during planarian regeneration.

Actin is an integral component of the cytoskeleton, which plays an important role in various fundamental cellular processes, such as affecting the polarity of embryonic cells during embryonic development in various model organisms. Meanwhile, previous studies have demonstrated that the polymerization of the actin cytoskeleton can affect cell migration, proliferation, and differentiation. Actin polymerization state regulated osteogenic differentiation and affected cell proliferation.

Whole-genome sequence of the planarian Dugesia japonica combining Illumina and PacBio data.

Advances in stem cell biology have posed the challenges in revealing the mechanistic themes underlying whole tissues and organs formation during regeneration. The planarian Dugesia japonica is an ideal model organism for the study of regeneration and stem cell biology. However, the genome resources for this species are still limited.

Is Required for Head Regeneration by Regulating Stem Cell Maintenance in Planarians.

SUMOylation and ubiquitylation are homologous processes catalyzed by homologous enzymes, and they are involved in nearly all aspects of eukaryotic biology. Planarians, which have the remarkable ability to regenerate their central nervous system (CNS), provide an excellent opportunity to investigate the molecular processes of CNS regeneration in vivo. In this study, we analyzed gene expression profiles during head regeneration with an RNA-seq-based screening approach and found that and were required for head regeneration in planarians.

CHIP promotes the activation of NF-κB signaling through enhancing the K63-linked ubiquitination of TAK1.

Transcriptional factor nuclear factor κB (NF-κB) can be activated by various intracellular or extracellular stimuli and its dysregulation leads to pathological conditions, such as neurodegenerative disorders, infection, and cancer. The carboxyl terminus of HSC70-interacting protein (CHIP), a pathogenic gene of spinocerebellar autosomal recessive 16 (SCAR16), plays an important roles in protein degradation, trafficking, and multiple signaling transductions. It has been reported that CHIP participates in the regulation of NF-κB signaling, and the mutant of CHIP (p.

TBX2/3 is required for regeneration of dorsal-ventral and medial-lateral polarity in planarians.

The molecular mechanisms responsible for axis establishment during non-embryonic processes remain elusive. The planarian flatworm is an ideal model organism to study body axis polarization and patterning in vivo. Here, we identified a homolog of the TBX2/3 in the planarian Dugesia japonica.

Tubgcp3 is a mitotic regulator of planarian epidermal differentiation.

Tubgcp3/GCP3 (The centrosomal protein γ-tubulin complex protein 3) is a component of the γ-tubulin small complexes (γ-TuSCs) and γ-tubulin ring complexes (γ-TuRCs), which play critical roles in mitotic spindle formation during mitosis. However, its function in stem cell development has not been thoroughly elucidated. The planarian flatworm, which contains a large number of adult somatic stem cells (neoblasts), is a unique model to study stem cell lineage development in vivo.

CHIP promotes Wnt signaling and regulates Arc stability by recruiting and polyubiquitinating LEF1 or Arc.

The carboxyl terminus of Hsc70-interacting protein (CHIP), an E3 ubiquitin ligase, participates in many cellular processes such as protein degradation, trafficking, autophagy, apoptosis, and multiple signaling transductions. The mutant of CHIP (p.T246M) causes the spinocerebellar autosomal recessive 16 (SCAR16), a neurodegenerative disease characterized by spinocerebellar atrophy.

Crystal structure of the yeast heterodimeric ADAT2/3 deaminase.

Background: The adenosine-to-inosine (A-to-I) editing in anticodons of tRNAs is critical for wobble base-pairing during translation. This modification is produced via deamination on A34 and catalyzed by the adenosine deaminase acting on tRNA (ADAT) enzyme. Eukaryotic ADATs are heterodimers composed of the catalytic subunit ADAT2 and the structural subunit ADAT3, but their molecular assemblies and catalytic mechanisms are largely unclear.

Application of next-generation sequencing in resistance genes of neoadjuvant chemotherapy for esophageal cancer.

Background: Neoadjuvant chemotherapy (NAC) has been proven to effectively improve the prognosis and long-term survival of patients with esophageal cancer (EC). But approximately 40% of patients are relatively insensitive to NAC. The mechanism underlying gene-induced resistance remains elusive.

TRIM25 Promotes TNF-α-Induced NF-κB Activation through Potentiating the K63-Linked Ubiquitination of TRAF2.

As an important effector in response to various intracellular or extracellular stimuli, the NF-κB family extensively participates in a wide spectrum of biological events, and its dysregulation may result in many pathological conditions, such as microbial infection, tumor progression, and neurodegenerative disorders. Previous investigations showed that multiple types of ubiquitination play critical roles in the modulation of the NF-κB signaling pathway, yet the molecular mechanisms are still poorly understood. In the current study, we identified TRIM25, an E3 ubiquitin ligase, as a novel positive regulator in mediating NF-κB activation in human embryonic kidney 293T (HEK293T), HeLa cells, THP-1 cells, and PBMCs.

Gain and loss events in the evolution of the apolipoprotein family in vertebrata.

Background: Various apolipoproteins widely distributed among vertebrata play key roles in lipid metabolism and have a direct correlation with human diseases as diagnostic markers. However, the evolutionary progress of apolipoproteins in species remains unclear. Nine human apolipoproteins and well-annotated genome data of 30 species were used to identify 210 apolipoprotein family members distributed among species from fish to humans.

Cdc42 regulate the apoptotic cell death required for planarian epidermal regeneration and homeostasis.

Rho GTPases have been shown previously to play important roles in several cellular processes by regulating the organization of the actin and microtubule cytoskeletons. However, the mechanisms of Rho GTPases that integrate the cellular responses during regeneration have not been thoroughly elucidated. The planarian flatworm, which contains a large number of adult somatic stem cells (neoblasts), is a unique model to study stem cell lineage development in vivo.

DjERas plays an important role in planarian regeneration and homeostasis.

The mechanisms of cell turnover including cell proliferation and cell differentiation were complex. Planarians possess amazing regeneration ability and undergo cell turnover throughout life. We identified a homologous gene of ERas by RNAi in Dugesia japonica.

homolog is required for planarian regeneration.

The planarian flatworm is an ideal system for the study of regeneration . In this study, we focus on TINP1, which is one of the most conserved proteins in eukaryotic organisms. We found that was expressed in parenchymal region through whole body as well as central nervous system (CNS) during the course of regeneration.

Exportin-1 is required for the maintenance of the planarian epidermal lineage.

Nucleocytoplasmic transport is essential for normal cellular function that mediates cargo transport from the cytoplasm to the nucleus. However, the mechanisms of nucleocytoplasmic transport that integrate stem cell development remain largely unknown. Since it has a large population of stem cells, the planarian flatworm is an ideal system for the study of adult stem cell lineage development in vivo.

Down-regulate of Djrfc2 causes tissues hypertrophy during planarian regeneration.

Planarians are an ideal model organism for regeneration research due to their amazing ability to regenerate. DNA replication is crucial for genome stability. Replication factor C (RFC), which is a replication factor C-like complex and plays an important role during DNA replication in eukaryotes, has been reported as a wound response factor during planarian regeneration.

SerRS-tRNASec complex structures reveal mechanism of the first step in selenocysteine biosynthesis.

Selenocysteine (Sec) is found in the catalytic centers of many selenoproteins and plays important roles in living organisms. Malfunctions of selenoproteins lead to various human disorders including cancer. Known as the 21st amino acid, the biosynthesis of Sec involves unusual pathways consisting of several stages.

Structural basis for recognition of G-1-containing tRNA by histidyl-tRNA synthetase.

Aminoacyl-tRNA synthetases (aaRSs) play a crucial role in protein translation by linking tRNAs with cognate amino acids. Among all the tRNAs, only tRNA(His) bears a guanine base at position -1 (G-1), and it serves as a major recognition element for histidyl-tRNA synthetase (HisRS). Despite strong interests in the histidylation mechanism, the tRNA recognition and aminoacylation details are not fully understood.

Cocrystal structures of glycyl-tRNA synthetase in complex with tRNA suggest multiple conformational states in glycylation.

Aminoacyl-tRNA synthetases are an ancient enzyme family that specifically charges tRNA molecules with cognate amino acids for protein synthesis. Glycyl-tRNA synthetase (GlyRS) is one of the most intriguing aminoacyl-tRNA synthetases due to its divergent quaternary structure and abnormal charging properties. In the past decade, mutations of human GlyRS (hGlyRS) were also found to be associated with Charcot-Marie-Tooth disease.

Cloning and identification of microRNAs in earthworm (Eisenia fetida).

MicroRNAs (miRNAs) (noncoding RNAs of 20-25 nucleotides) play important roles in the post-transcriptional regulation of gene expression in various eukaryotes and prokaryotes. Piwi-interacting RNAs function by combining with PIWI proteins to regulate protein synthesis and to stabilize mRNA, the chromatin framework, and genome structure. This study investigates the role of miRNAs in regeneration.