The DNA methyltransferase DMAP1 is required for tissue maintenance and planarian regeneration.

The precise regulation of transcription is required for embryonic development, adult tissue turnover, and regeneration. Epigenetic modifications play a crucial role in orchestrating and regulating the transcription of genes. These modifications are important in the transition of pluripotent stem cells and their progeny.

The DNA Methyltransferase DMAP1 is Required for Tissue Maintenance and Planarian Regeneration.

The precise regulation of transcription is required for embryonic development, adult tissue turnover, and regeneration. Epigenetic modifications play a crucial role in orchestrating and regulating the transcription of genes. These modifications are important in the transition of pluripotent stem cells and their progeny.

FLASH-RT does not affect chromosome translocations and junction structures beyond that of CONV-RT dose-rates.

Background And Purpose: The impact of radiotherapy (RT) at ultra high vs conventional dose rate (FLASH vs CONV) on the generation and repair of DNA double strand breaks (DSBs) is an important question that remains to be investigated. Here, we tested the hypothesis as to whether FLASH-RT generates decreased chromosomal translocations compared to CONV-RT.

Materials And Methods: We used two FLASH validated electron beams and high-throughput rejoin and genome-wide translocation sequencing (HTGTS-JoinT-seq), employing S.

Analysis of DNA Double-Stranded Breaks Using the Comet Assay in Planarians.

Comet assay provides the opportunity to detect and characterize DNA strand breaks. Cellular lysing followed by embedding in agarose slide is used to visualize under an electrical current migration patterns corresponding to DNA fragments of different sizes. Here we describe the process of detecting and characterizing DNA damage by Comet assay on planarians, which is a model organism commonly used to understand the process of whole-body regeneration, stem cell regulation, and adult tissue maintenance.

Restoration of DNA integrity and the cell cycle by electric stimulation in planarian tissues damaged by ionizing radiation.

Exposure to high levels of ionizing γ radiation leads to irreversible DNA damage and cell death. Here, we establish that exogenous application of electric stimulation enables cellular plasticity and the re-establishment of stem cell activity in tissues damaged by ionizing radiation. We show that subthreshold direct current stimulation (DCS) rapidly restores pluripotent stem cell populations previously eliminated by lethally γ-irradiated tissues of the planarian flatworm Schmidtea mediterranea.

Whole planarian chromosome squash.

Whole planarian chromosome squash allows researchers to qualitatively analyze chromosome integrity. Treatment with colchicine is used to halt dividing cells within metaphase and does not require amputation or tissue puncturing. In combination with acetic-orcein, a stain-fixative for chromosomes, this strategy is suitable for animals with friable tissues caused by drug treatment, radiation, and RNA interference phenotypes.

TRAF-like Proteins Regulate Cellular Survival in the Planarian .

Tissue homeostasis relies on the timely renewal of cells that have been damaged or have surpassed their biological age. Nonetheless, the underlying molecular mechanism coordinating tissue renewal is unknown. The planarian harbors a large population of stem cells that continuously divide to support the restoration of tissues throughout the body.

Poly(ADP-Ribose) Polymerase-3 Regulates Regeneration in Planarians.

Protein ADP-ribosylation is a reversible post-translational modification (PTM) process that plays fundamental roles in cell signaling. The covalent attachment of ADP ribose polymers is executed by PAR polymerases (PARP) and it is essential for chromatin organization, DNA repair, cell cycle, transcription, and replication, among other critical cellular events. The process of PARylation or polyADP-ribosylation is dynamic and takes place across many tissues undergoing renewal and repair, but the molecular mechanisms regulating this PTM remain mostly unknown.

The planarian Schmidtea mediterranea is a new model to study host-pathogen interactions during fungal infections.

Candida albicans is one of the most common fungal pathogens of humans. Currently, there are limitations in the evaluation of C. albicans infection in existing animal models, especially in terms of understanding the influence of specific infectious stages of the fungal pathogen on the host.

DNA damage and tissue repair: What we can learn from planaria.

Faithful renewal of aging and damaged tissues is central to organismal lifespan. Stem cells (SCs) generate the cellular progeny that replenish adult tissues across the body but this task becomes increasingly compromised over time. The age related decline in SC-mediated tissue maintenance is a multifactorial event that commonly affects genome integrity.

SUMOylation controls stem cell proliferation and regional cell death through Hedgehog signaling in planarians.

Mechanisms underlying anteroposterior body axis differences during adult tissue maintenance and regeneration are poorly understood. Here, we identify that post-translational modifications through the SUMO (Small Ubiquitin-like Modifier) machinery are evolutionarily conserved in the Lophotrocozoan Schmidtea mediterranea. Disruption of SUMOylation in adult animals by RNA-interference of the only SUMO E2 conjugating enzyme Ubc9 leads to a systemic increase in DNA damage and a remarkable regional defect characterized by increased cell death and loss of the posterior half of the body.

The Akt signaling pathway is required for tissue maintenance and regeneration in planarians.

Background: Akt (PKB) is a serine threonine protein kinase downstream of the phosphoinositide 3-kinase (PI3K) pathway. In mammals, Akt is ubiquitously expressed and is associated with regulation of cellular proliferation, metabolism, cell growth and cell death. Akt has been widely studied for its central role in physiology and disease, in particular cancer where it has become an attractive pharmacological target.

Regional signals in the planarian body guide stem cell fate in the presence of genomic instability.

Cellular fate decisions are influenced by their topographical location in the adult body. For instance, tissue repair and neoplastic growth are greater in anterior than in posterior regions of adult animals. However, the molecular underpinnings of these regional differences are unknown.

Bioelectrical regulation of cell cycle and the planarian model system.

Cell cycle regulation through the manipulation of endogenous membrane potentials offers tremendous opportunities to control cellular processes during tissue repair and cancer formation. However, the molecular mechanisms by which biophysical signals modulate the cell cycle remain underappreciated and poorly understood. Cells in complex organisms generate and maintain a constant voltage gradient across the plasma membrane known as the transmembrane potential.