@article {1160, title = {Cytoplasmic poly (A)-binding protein critically regulates epidermal maintenance and turnover in the planarian .}, journal = {Development}, volume = {144}, year = {2017}, month = {2017 09 01}, pages = {3066-3079}, abstract = {

Identifying key cellular events that facilitate stem cell function and tissue organization is crucial for understanding the process of regeneration. Planarians are powerful model system to study regeneration and stem cell (neoblast) function. Here, using planaria, we show that the initial events of regeneration, such as epithelialization and epidermal organization are critically regulated by a novel cytoplasmic poly A-binding protein, SMED-PABPC2. Knockdown leads to defects in epidermal lineage specification, disorganization of epidermis and ECM, and deregulated wound healing, resulting in the selective failure of neoblast proliferation near the wound region. Polysome profiling suggests that epidermal lineage transcripts, including , are translationally regulated by SMED-PABPC2 Together, our results uncover a novel role for SMED-PABPC2 in the maintenance of epidermal and ECM integrity, critical for wound healing and subsequent processes for regeneration.

}, keywords = {Animals, Cell Lineage, Cell Proliferation, Cytoplasm, Epidermis, Epithelium, Extracellular Matrix, Gene Knockdown Techniques, Homeostasis, Models, Biological, Planarians, Poly(A)-Binding Protein I, Regeneration, RNA, Messenger, Wound Healing}, issn = {1477-9129}, doi = {10.1242/dev.152942}, author = {Bansal, Dhiru and Kulkarni, Jahnavi and Nadahalli, Kavana and Lakshmanan, Vairavan and Krishna, Srikar and Sasidharan, Vidyanand and Geo, Jini and Dilipkumar, Shilpa and Pasricha, Renu and Gulyani, Akash and Raghavan, Srikala and Palakodeti, Dasaradhi} } @article {1199, title = {The miR-124 family of microRNAs is crucial for regeneration of the brain and visual system in the planarian Schmidtea mediterranea}, journal = {Development}, volume = {144}, year = {2017}, pages = {3211{\textendash}3223}, abstract = {

Brain regeneration in planarians is mediated by precise spatiotemporal control of gene expression and is crucial for multiple aspects of neurogenesis. However, the mechanisms underpinning the gene regulation essential for brain regeneration are largely unknown. Here, we investigated the role of the miR-124 family of microRNAs in planarian brain regeneration. The miR-124 family (miR-124) is highly conserved in animals and regulates neurogenesis by facilitating neural differentiation, yet its role in neural wiring and brain organization is not known. We developed a novel method for delivering anti-miRs using liposomes for the functional knockdown of microRNAs. Smed-miR-124 knockdown revealed a key role for these microRNAs in neuronal organization during planarian brain regeneration. Our results also demonstrated an essential role for miR-124 in the generation of eye progenitors. Additionally, miR-124 regulates Smed-slit-1, which encodes an axon guidance protein, either by targeting slit-1 mRNA or, potentially, by modulating the canonical Notch pathway. Together, our results reveal a role for miR-124 in regulating the regeneration of a functional brain and visual system.

}, issn = {0950-1991}, doi = {10.1242/dev.144758}, url = {http://dev.biologists.org/content/144/18/3211}, author = {Sasidharan, Vidyanand and Marepally, Srujan and Elliott, Sarah A. and Baid, Srishti and Lakshmanan, Vairavan and Nayyar, Nishtha and Bansal, Dhiru and S{\'a}nchez Alvarado, Alejandro and Vemula, Praveen Kumar and Palakodeti, Dasaradhi} } @article {1170, title = {Genome-Wide Analysis of Polyadenylation Events in Schmidtea mediterranea.}, journal = {G3 (Bethesda)}, volume = {6}, year = {2016}, month = {2016 10 13}, pages = {3035-3048}, abstract = {

In eukaryotes, 3{\textquoteright} untranslated regions (UTRs) play important roles in regulating posttranscriptional gene expression. The 3{\textquoteright}UTR is defined by regulated cleavage/polyadenylation of the pre-mRNA. The advent of next-generation sequencing technology has now enabled us to identify these events on a genome-wide scale. In this study, we used poly(A)-position profiling by sequencing (3P-Seq) to capture all poly(A) sites across the genome of the freshwater planarian, Schmidtea mediterranea, an ideal model system for exploring the process of regeneration and stem cell function. We identified the 3{\textquoteright}UTRs for \~{}14,000 transcripts and thus improved the existing gene annotations. We found 97 transcripts, which are polyadenylated within an internal exon, resulting in the shrinking of the ORF and loss of a predicted protein domain. Around 40\% of the transcripts in planaria were alternatively polyadenylated (ApA), resulting either in an altered 3{\textquoteright}UTR or a change in coding sequence. We identified specific ApA transcript isoforms that were subjected to miRNA mediated gene regulation using degradome sequencing. In this study, we also confirmed a tissue-specific expression pattern for alternate polyadenylated transcripts. The insights from this study highlight the potential role of ApA in regulating the gene expression essential for planarian regeneration.

}, keywords = {3{\textquoteright} Untranslated Regions, Animals, Computational Biology, Genome, Helminth, Genome-Wide Association Study, High-Throughput Nucleotide Sequencing, MicroRNAs, Molecular Sequence Annotation, Platyhelminths, Poly A, Polyadenylation, Reproducibility of Results, RNA Interference, RNA Processing, Post-Transcriptional, RNA, Messenger}, issn = {2160-1836}, doi = {10.1534/g3.116.031120}, author = {Lakshmanan, Vairavan and Bansal, Dhiru and Kulkarni, Jahnavi and Poduval, Deepak and Krishna, Srikar and Sasidharan, Vidyanand and Anand, Praveen and Seshasayee, Aswin and Palakodeti, Dasaradhi} }