@article {1186, title = {Networks that link cytoskeletal regulators and diaphragm proteins underpin filtration function in Drosophila nephrocytes.}, journal = {Exp Cell Res}, volume = {364}, year = {2018}, month = {2018 Mar 15}, pages = {234-242}, abstract = {

Insect nephrocytes provide a valuable model for kidney disease, as they are structurally and functionally homologous to mammalian kidney podocytes. They possess an exceptional macromolecular assembly, the nephrocyte diaphragm (ND), which serves as a filtration barrier and helps maintain tissue homeostasis by filtering out wastes and toxic products. However, the elements that maintain nephrocyte architecture and the ND are not understood. We show that Drosophila nephrocytes have a unique cytoplasmic cluster of F-actin, which is maintained by the microtubule cytoskeleton and Rho-GTPases. A balance of Rac1 and Cdc42 activity as well as proper microtubule organization and endoplasmic reticulum structure, are required to position the actin cluster. Further, ND proteins Sns and Duf also localize to this cluster and regulate organization of the actin and microtubule cytoskeleton. Perturbation of any of these inter-dependent components impairs nephrocyte ultrafiltration. Thus cytoskeletal components, Rho-GTPases and ND proteins work in concert to maintain the specialized nephrocyte architecture and function.

}, issn = {1090-2422}, doi = {10.1016/j.yexcr.2018.02.015}, author = {Muraleedharan, Simi and Sam, Aksah and Skaer, Helen and Inamdar, Maneesha S} } @article {1589, title = {OCIAD1 Controls Electron Transport Chain Complex I Activity to Regulate Energy Metabolism in Human Pluripotent Stem Cells.}, journal = {Stem Cell Reports}, volume = {11}, year = {2018}, month = {2018 Jul 10}, pages = {128-141}, abstract = {

Pluripotent stem cells (PSCs) derive energy predominantly from glycolysis and not the energy-efficient oxidative phosphorylation (OXPHOS). Differentiation is initiated with energy metabolic shift from glycolysis to OXPHOS. We investigated the role of mitochondrial energy metabolism in human PSCs using molecular, biochemical, genetic, and pharmacological approaches. We show that the carcinoma protein OCIAD1 interacts with and regulates mitochondrial complex I activity. Energy metabolic assays on live pluripotent cells showed that OCIAD1-depleted cells have increased OXPHOS and may be poised for differentiation. OCIAD1 maintains human embryonic stem cells, and its depletion by CRISPR/Cas9-mediated knockout leads to rapid and increased differentiation upon induction, whereas OCIAD1 overexpression has the opposite effect. Pharmacological alteration of complex I activity was able to rescue the defects of OCIAD1 modulation. Thus, hPSCs can exist in energy metabolic substates. OCIAD1 provides a target to screen for additional modulators of mitochondrial activity to promote transient multipotent precursor expansion or enhance differentiation.

}, issn = {2213-6711}, doi = {10.1016/j.stemcr.2018.05.015}, author = {Shetty, Deeti K and Kalamkar, Kaustubh P and Inamdar, Maneesha S} } @article {1151, title = {Rudhira/BCAS3 is essential for mouse development and cardiovascular patterning.}, journal = {Sci Rep}, volume = {8}, year = {2018}, month = {2018 Apr 04}, pages = {5632}, abstract = {

Rudhira/Breast Carcinoma Amplified Sequence 3 (BCAS3) is a cytoskeletal protein that promotes directional cell migration and angiogenesis in vitro and is implicated in human carcinomas and coronary artery disease. To study the role of Rudhira during development in vivo, we generated the first knockout mouse for rudhira and show that Rudhira is essential for mouse development. Rudhira null embryos die at embryonic day (E) 9.5 accompanied by severe vascular patterning defects in embryonic and extra-embryonic tissues. To identify the molecular processes downstream of rudhira, we analyzed the transcriptome of intact knockout yolk sacs. Genome-wide transcriptome analysis showed that Rudhira functions in angiogenesis and its related processes such as cell adhesion, extracellular matrix organization, peptidase activity and TGFβ signaling. Since Rudhira is also expressed in endothelial cells\ (ECs), we further generated Tie2Cre-mediated endothelial knockout (CKO) of rudhira. CKO embryos survive to E11.5 and similar to the global knockout, display gross vascular patterning defects, showing that endothelial Rudhira is vital for development. Further, Rudhira knockdown ECs in culture fail to sprout in a spheroid-sprouting assay, strongly supporting its role in vascular patterning. Our study identifies an essential role for Rudhira in blood vessel remodeling and provides a mouse model for cardiovascular development.

}, issn = {2045-2322}, doi = {10.1038/s41598-018-24014-w}, author = {Shetty, Ronak and Joshi, Divyesh and Jain, Mamta and Vasudevan, Madavan and Paul, Jasper Chrysolite and Bhat, Ganesh and Banerjee, Poulomi and Abe, Takaya and Kiyonari, Hiroshi and VijayRaghavan, K and Inamdar, Maneesha S} }