Erythropoiesis, the production of red blood cells, is an essential process in mammals. The unique shape and composition of red blood cells requires the removal of cellular organelles and macromolecular structures during the maturation of these cells. This clearance is orchestrated by the processes of autophagy including mitophagy, cytoskeletal reorganization and nuclear condensation and elimination. However, these inherently cell damaging and destructive processes must be deployed in a carefully calibrated and stringently regulated manner to prevent untimely cell death and lineage ablation. The laboratory recently discovered that the transcriptional repressor GFI1B (growth factor independence 1b) is a critical regulator of autophagy. The role of GFI1B in inhibiting autophagy was initially indicated by chromatin immunoprecipitation screens which uncovered several mediators of autophagy and apoptosis to be potential GFI1B genomic targets. This observation was extended by others that showed a significant increase in autophagy and apoptosis in GFI1B mutants, which could explain ablation of the erythroid lineage and embryonic lethality in the mutant embryos.
To investigate the role of GFI1B in regulating autophagy, I first performed an in-silica analysis of the genomic loci of several autophagy mediators (not previously detected in the ChIP screens) to determine the presence of consensus GFI1B binding sites within their loci. This was followed by ChIP-qPCR experiments with erythroid progenitor cells to confirm recruitment of GFI1B and its co-factor LSD1/KDM1A (lysine specific demethylase1) to genomic sequences within several autophagy genes including FOXO3, ATG5, BNIP3L, BNIP3 and ATG10. Finally, to establish transcriptional regulation of select genes by GFI1B, I performed luciferase reporter assays on genomic elements following transient co-transfections into a non-erythroid cell line. Our results demonstrated transcriptional repression of intronic DNA elements from the FOXO3 and BNIP3 genes by GFI1B. Overall, the results of the experiments of my thesis, indicate transcriptional repression of autophagy genes by GFI1B as a vital strategy in preventing excessive autophagic flux and cell death during erythroid development. These results provide key insights in understanding the balanced regulation of autophagy during mammalian erythropoiesis.
","abstract_html":"<p>Erythropoiesis, the production of red blood cells, is an essential process in mammals. The unique shape and composition of red blood cells requires the removal of cellular organelles and macromolecular structures during the maturation of these cells. This clearance is orchestrated by the processes of autophagy including mitophagy, cytoskeletal reorganization and nuclear condensation and elimination. However, these inherently cell damaging and destructive processes must be deployed in a carefully calibrated and stringently regulated manner to prevent untimely cell death and lineage ablation. The laboratory recently discovered that the transcriptional repressor GFI1B (growth factor independence 1b) is a critical regulator of autophagy. The role of GFI1B in inhibiting autophagy was initially indicated by chromatin immunoprecipitation screens which uncovered several mediators of autophagy and apoptosis to be potential GFI1B genomic targets. This observation was extended by others that showed a significant increase in autophagy and apoptosis in <em>GFI1B</em> mutants, which could explain ablation of the erythroid lineage and embryonic lethality in the mutant embryos.</p> <p>To investigate the role of GFI1B in regulating autophagy, I first performed an <em>in-silica</em> analysis of the genomic loci of several autophagy mediators (not previously detected in the ChIP screens) to determine the presence of consensus GFI1B binding sites within their loci. This was followed by ChIP-qPCR experiments with erythroid progenitor cells to confirm recruitment of GFI1B and its co-factor LSD1/KDM1A (lysine specific demethylase1) to genomic sequences within several autophagy genes including <em>FOXO3, ATG5, BNIP3L,</em> <em>BNIP3 </em>and <em>ATG10</em>. Finally, to establish transcriptional regulation of select genes by GFI1B, I performed luciferase reporter assays on genomic elements following transient co-transfections into a non-erythroid cell line. Our results demonstrated transcriptional repression of intronic DNA elements from the FOXO3 and BNIP3 genes by GFI1B. Overall, the results of the experiments of my thesis, indicate transcriptional repression of autophagy genes by GFI1B as a vital strategy in preventing excessive autophagic flux and cell death during erythroid development. These results provide key insights in understanding the balanced regulation of autophagy during mammalian erythropoiesis.</p>","abstract_has_math":false,"creators":["Kelkar, Nikita Uday"],"institution":null,"degree_name":"Master of Science (M.S.)","degree_level":"Thesis","degree_discipline":"Biology","degree_department":null,"school":null,"contributors":["Shireen Saleque","Shubha Govind","Mark Emerson"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2025,"date_issued":"2025-01-01T08:00:00Z","date_published":"2025-01-01T08:00:00Z","updated_at":"2026-07-24T01:58:07Z","subjects":["Autophagy","Erythropoiesis","Epigenetics","Developmental Biology","Molecular Biology","Biotechnology"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://academicworks.cuny.edu/cc_etds_theses/1195","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Shireen Saleque","Shubha Govind","Mark Emerson"]},{"key":"dc:creator","label":"Author","values":["Kelkar, Nikita Uday"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2027-04-21T07:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Biology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science (M.S.)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Autophagy","Erythropoiesis","Epigenetics","Developmental Biology","Molecular Biology","Biotechnology"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://academicworks.cuny.edu/cc_etds_theses/1195"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Erythropoiesis, the production of red blood cells, is an essential process in mammals. The unique shape and composition of red blood cells requires the removal of cellular organelles and macromolecular structures during the maturation of these cells. This clearance is orchestrated by the processes of autophagy including mitophagy, cytoskeletal reorganization and nuclear condensation and elimination. However, these inherently cell damaging and destructive processes must be deployed in a carefully calibrated and stringently regulated manner to prevent untimely cell death and lineage ablation. The laboratory recently discovered that the transcriptional repressor GFI1B (growth factor independence 1b) is a critical regulator of autophagy. The role of GFI1B in inhibiting autophagy was initially indicated by chromatin immunoprecipitation screens which uncovered several mediators of autophagy and apoptosis to be potential GFI1B genomic targets. This observation was extended by others that showed a significant increase in autophagy and apoptosis in GFI1B mutants, which could explain ablation of the erythroid lineage and embryonic lethality in the mutant embryos.
To investigate the role of GFI1B in regulating autophagy, I first performed an in-silica analysis of the genomic loci of several autophagy mediators (not previously detected in the ChIP screens) to determine the presence of consensus GFI1B binding sites within their loci. This was followed by ChIP-qPCR experiments with erythroid progenitor cells to confirm recruitment of GFI1B and its co-factor LSD1/KDM1A (lysine specific demethylase1) to genomic sequences within several autophagy genes including FOXO3, ATG5, BNIP3L, BNIP3 and ATG10. Finally, to establish transcriptional regulation of select genes by GFI1B, I performed luciferase reporter assays on genomic elements following transient co-transfections into a non-erythroid cell line. Our results demonstrated transcriptional repression of intronic DNA elements from the FOXO3 and BNIP3 genes by GFI1B. Overall, the results of the experiments of my thesis, indicate transcriptional repression of autophagy genes by GFI1B as a vital strategy in preventing excessive autophagic flux and cell death during erythroid development. These results provide key insights in understanding the balanced regulation of autophagy during mammalian erythropoiesis.
"]},{"key":"dc:title","label":"Title","values":["Repression Of Autophagy During Erythroid Development By Gfi1b"]}]}],"canonical_facts":{"dc:contributor":["Shireen Saleque","Shubha Govind","Mark Emerson"],"dc:creator":["Kelkar, Nikita Uday"],"dc:date.available":["2027-04-21T07:00:00Z"],"dc:description.abstract":["Erythropoiesis, the production of red blood cells, is an essential process in mammals. The unique shape and composition of red blood cells requires the removal of cellular organelles and macromolecular structures during the maturation of these cells. This clearance is orchestrated by the processes of autophagy including mitophagy, cytoskeletal reorganization and nuclear condensation and elimination. However, these inherently cell damaging and destructive processes must be deployed in a carefully calibrated and stringently regulated manner to prevent untimely cell death and lineage ablation. The laboratory recently discovered that the transcriptional repressor GFI1B (growth factor independence 1b) is a critical regulator of autophagy. The role of GFI1B in inhibiting autophagy was initially indicated by chromatin immunoprecipitation screens which uncovered several mediators of autophagy and apoptosis to be potential GFI1B genomic targets. This observation was extended by others that showed a significant increase in autophagy and apoptosis in GFI1B mutants, which could explain ablation of the erythroid lineage and embryonic lethality in the mutant embryos.
To investigate the role of GFI1B in regulating autophagy, I first performed an in-silica analysis of the genomic loci of several autophagy mediators (not previously detected in the ChIP screens) to determine the presence of consensus GFI1B binding sites within their loci. This was followed by ChIP-qPCR experiments with erythroid progenitor cells to confirm recruitment of GFI1B and its co-factor LSD1/KDM1A (lysine specific demethylase1) to genomic sequences within several autophagy genes including FOXO3, ATG5, BNIP3L, BNIP3 and ATG10. Finally, to establish transcriptional regulation of select genes by GFI1B, I performed luciferase reporter assays on genomic elements following transient co-transfections into a non-erythroid cell line. Our results demonstrated transcriptional repression of intronic DNA elements from the FOXO3 and BNIP3 genes by GFI1B. Overall, the results of the experiments of my thesis, indicate transcriptional repression of autophagy genes by GFI1B as a vital strategy in preventing excessive autophagic flux and cell death during erythroid development. These results provide key insights in understanding the balanced regulation of autophagy during mammalian erythropoiesis.
"],"dc:identifier":["https://academicworks.cuny.edu/cc_etds_theses/1195"],"dc:subject":["Autophagy","Erythropoiesis","Epigenetics","Developmental Biology","Molecular Biology","Biotechnology"],"dc:title":["Repression Of Autophagy During Erythroid Development By Gfi1b"],"thesis:degree_discipline":["Biology"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["Master of Science (M.S.)"]},"updated_at":"2026-07-24T01:58:07Z"}