@article {3341, title = {Erythroid lineage-specific lentiviral RNAi vectors suitable for molecular functional studies and therapeutic applications.}, journal = {Sci Rep}, volume = {12}, year = {2022}, month = {2022 08 18}, pages = {14033}, abstract = {

Numerous genes exert multifaceted roles in hematopoiesis. Therefore, we generated novel\ lineage-specific RNA interference\ (RNAi) lentiviral\ vectors, H23B-Ery-Lin-shRNA\ and H234B-Ery-Lin-shRNA, to probe the functions of these genes in erythroid cells\ without affecting other hematopoietic lineages. The lineage specificity of these vectors was confirmed by\ transducing multiple hematopoietic cells to express a fluorescent protein. Unlike the previously reported erythroid lineage RNAi vector, our vectors were designed for cloning the short hairpin RNAs (shRNAs) for\ any gene, and they also provide superior knockdown of the target gene expression with a\ single shRNA integration per cell. High-level lineage-specific downregulation of BCL11A and ZBTB7A,\ two\ well-characterized transcriptional repressors of HBG in adult erythroid cells, was achieved with substantial induction of fetal hemoglobin with a single-copy lentiviral vector integration. Transduction of primary healthy donor CD34 cells with these vectors resulted in\ \>80\% reduction in the target\ protein levels and up to 40\% elevation in the γ-chain levels in the differentiated erythroid cells. Xenotransplantation of the human CD34 cells transduced with H23B-Ery-Lin-shBCL11A\ LV in immunocompromised mice showed ~ 60\% reduction in BCL11A protein expression with ~\ 40\% elevation of γ-chain levels in the erythroid cells derived from the transduced CD34 cells. Overall, the novel erythroid lineage-specific lentiviral RNAi vectors described in this study provide a\ high-level knockdown of target gene expression in the erythroid cells, making them suitable for their use in gene therapy for hemoglobinopathies. Additionally, the design of these vectors also makes them ideal for high-throughput RNAi screening for studying normal and pathological erythropoiesis.

}, keywords = {Animals, Cell Line, Tumor, Cell Lineage, DNA-Binding Proteins, Genetic Vectors, Humans, Lentivirus, Mice, RNA Interference, RNA, Small Interfering, Transcription Factors, Transduction, Genetic}, issn = {2045-2322}, doi = {10.1038/s41598-022-13783-0}, author = {Bagchi, Abhirup and Devaraju, Nivedhitha and Chambayil, Karthik and Rajendiran, Vignesh and Venkatesan, Vigneshwaran and Sayed, Nilofer and Pai, Aswin Anand and Nath, Aneesha and David, Ernest and Nakamura, Yukio and Balasubramanian, Poonkuzhali and Srivastava, Alok and Thangavel, Saravanabhavan and Mohankumar, Kumarasamypet M and Velayudhan, Shaji R} } @article {2373, title = {A regulatory network of microRNAs confers lineage commitment during early developmental trajectories of B and T lymphocytes.}, journal = {Proc Natl Acad Sci U S A}, volume = {118}, year = {2021}, month = {2021 11 16}, abstract = {

The commitment of hematopoietic multipotent progenitors (MPPs) toward a particular lineage involves activation of cell type-specific genes and silencing of genes that promote alternate cell fates. Although the gene expression programs of early-B and early-T lymphocyte development are mutually exclusive, we show that these cell types exhibit significantly correlated microRNA (miRNA) profiles. However, their corresponding miRNA targetomes are distinct and predominated by transcripts associated with natural killer, dendritic cell, and myeloid lineages, suggesting that miRNAs function in a cell-autonomous manner. The combinatorial expression of miRNAs miR-186-5p, miR-128-3p, and miR-330-5p in MPPs significantly attenuates their myeloid differentiation potential due to repression of myeloid-associated transcripts. Depletion of these miRNAs caused a pronounced de-repression of myeloid lineage targets in differentiating early-B and early-T cells, resulting in a mixed-lineage gene expression pattern. De novo motif analysis combined with an assay of promoter activities indicates that B as well as T lineage determinants drive the expression of these miRNAs in lymphoid lineages. Collectively, we present a paradigm that miRNAs are conserved between developing B and T lymphocytes, yet they target distinct sets of promiscuously expressed lineage-inappropriate genes to suppress the alternate cell-fate options. Thus, our studies provide a comprehensive compendium of miRNAs with functional implications for B and T lymphocyte development.

}, keywords = {Animals, B-Lymphocytes, Cell Differentiation, Cell Lineage, Gene Expression, Gene Expression Profiling, Gene Regulatory Networks, Hematopoietic Stem Cells, Mice, MicroRNAs, Myeloid Cells, T-Lymphocytes}, issn = {1091-6490}, doi = {10.1073/pnas.2104297118}, author = {Nikhat, Sameena and Yadavalli, Anurupa D and Prusty, Arpita and Narayan, Priyanka K and Palakodeti, Dasaradhi and Murre, Cornelis and Pongubala, Jagan M R} } @article {1158, title = {Co-expression of Tbx6 and Sox2 identifies a novel transient neuromesoderm progenitor cell state.}, journal = {Development}, volume = {144}, year = {2017}, month = {2017 12 15}, pages = {4522-4529}, abstract = {

Elongation of the body axis is a key aspect of body plan development. Bipotential neuromesoderm progenitors (NMPs) ensure axial growth of embryos by contributing both to the spinal cord and mesoderm. The current model for the mechanism controlling NMP deployment invokes Tbx6, a T-box factor, to drive mesoderm differentiation of NMPs. Here, we identify a new population of Tbx6 cells in a subdomain of the NMP niche in mouse embryos. Based on co-expression of a progenitor marker, Sox2, we identify this population as representing a transient cell state in the mesoderm-fated NMP lineage. Genetic lineage tracing confirms the presence of the NMP cell state. Furthermore, we report a novel aspect of the documented mutant phenotype, namely an increase from two to four ectopic neural tubes, corresponding to the switch in NMP niche, thus highlighting the importance of function in NMP fate decision. This study emphasizes the function of Tbx6 as a bistable switch that turns mesoderm fate {\textquoteright}on{\textquoteright} and progenitor state {\textquoteright}off{\textquoteright}, and thus has implications for the molecular mechanism driving NMP fate choice.

}, keywords = {Animals, Body Patterning, Cell Differentiation, Cell Lineage, Embryonic Stem Cells, Gene Expression Regulation, Developmental, Mesoderm, Mice, Mice, Transgenic, Neural Tube, SOXB1 Transcription Factors, Spinal Cord, Transcription Factors}, issn = {1477-9129}, doi = {10.1242/dev.153262}, author = {Javali, Alok and Misra, Aritra and Leonavicius, Karolis and Acharyya, Debalina and Vyas, Bhakti and Sambasivan, Ramkumar} } @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} }