Using a combination of second generation mRNA sequencing and bioinformatic approaches we have obtained a complete list of mRNAs expressed at each stage of development from the CFU-E stage to the enucleating erythroblast. We identified 14 genes that are strongly upregulated during this period and that encode transcription factors, chromatin-modifying enzymes, RNA Polymerase II elongation factors, or DNA binding proteins that have important roles in other developmental processes but whose functions in red cell development have never been explored: Runx1t1, Sertad2, SertadS, Mxd1, Mxd3, Btg2, Med13l, Ncoa7, Calcocol, Asf1b, Dedd2, Bag1, Hdac11, HEXIM1, and EII2.
In Aim 1 we will determine which of these 14 proteins plays an important role in erythroid development from the CFU-E stage by systematically knocking down each in purified CFU-E cells and culturing them in the presence of Epo. Broad effects will be assayed by measuring proliferation, induction of CD-71 and Ter-119, nuclear condensation, enucleation, and accumulation of hemoglobin and other marker erythroid- important genes. In collaboration with the Zon laboratory we will knockdown each of these in zebra fish embryos and assess effects on erythropoiesis.
In Aim 2, for HDAC2, Hipk-1 and -2, and the new factors that have the most dramatic effects on erythropoiesis when knocked down, we will determine the genes whose expression is directly and indirectly regulated by them, using second generation mRNA sequencing on cultured knockdown mouse progenitors. Finally, in Aim #3 we will determine the global roles of these factors on Polll binding to promoter regions, Polll elongation, and in some cases epigenetic histone modifications As example, using progenitors in which the factors have been knocked down, we will measure by Chip-seq the global distributions of Polll and two histone modifications characteristic of transcriptional elongation. Coupled with bioinformatic analysis we will determine whether control of erythroid- important gene transcription during erythropoiesis by each of these factors works at the level of Polll binding or Polll elongation. These and other studies will create an extensive framework for understanding the epigenetic and transcriptional regulatory networks active in terminal erythropoiesis.

Public Health Relevance

Many diseases are caused by disfunctions in red cell development - anemias such as thalassemia, Diamond Blackfan Anemia, sideroblastic anemia, and aplastic anemia - to leukemias and other myelodysplastic disorders. A comprehensive knowledge ofthe proteins that govern gene expression during red cell development is essential to uncover the mechanisms underlying these diseases and developing new treatment options.

National Institute of Health (NIH)
National Heart, Lung, and Blood Institute (NHLBI)
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Heart, Lung, and Blood Initial Review Group (HLBP)
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Children's Hospital Boston
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Chung, Jacky; Wittig, Johannes G; Ghamari, Alireza et al. (2017) Erythropoietin signaling regulates heme biosynthesis. Elife 6:
Kafina, Martin D; Paw, Barry H (2017) Intracellular iron and heme trafficking and metabolism in developing erythroblasts. Metallomics 9:1193-1203
Doulatov, Sergei; Vo, Linda T; Macari, Elizabeth R et al. (2017) Drug discovery for Diamond-Blackfan anemia using reprogrammed hematopoietic progenitors. Sci Transl Med 9:
Seguin, Alexandra; Takahashi-Makise, Naoko; Yien, Yvette Y et al. (2017) Reductions in the mitochondrial ABC transporter Abcb10 affect the transcriptional profile of heme biosynthesis genes. J Biol Chem 292:16284-16299
Grillo, Anthony S; SantaMaria, Anna M; Kafina, Martin D et al. (2017) Restored iron transport by a small molecule promotes absorption and hemoglobinization in animals. Science 356:608-616
Yien, Yvette Y; Ducamp, Sarah; van der Vorm, Lisa N et al. (2017) Mutation in human CLPX elevates levels of ?-aminolevulinate synthase and protoporphyrin IX to promote erythropoietic protoporphyria. Proc Natl Acad Sci U S A 114:E8045-E8052
Gao, Xiaofei; Lee, Hsiang-Ying; Li, Wenbo et al. (2017) Thyroid hormone receptor beta and NCOA4 regulate terminal erythrocyte differentiation. Proc Natl Acad Sci U S A 114:10107-10112
Perlin, Julie R; Robertson, Anne L; Zon, Leonard I (2017) Efforts to enhance blood stem cell engraftment: Recent insights from zebrafish hematopoiesis. J Exp Med 214:2817-2827
Perlin, Julie R; Sporrij, Audrey; Zon, Leonard I (2017) Blood on the tracks: hematopoietic stem cell-endothelial cell interactions in homing and engraftment. J Mol Med (Berl) 95:809-819
van Rooij, Frank J A; Qayyum, Rehan; Smith, Albert V et al. (2017) Genome-wide Trans-ethnic Meta-analysis Identifies Seven Genetic Loci Influencing Erythrocyte Traits and a Role for RBPMS in Erythropoiesis. Am J Hum Genet 100:51-63

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