Bieker Laboratory

Bieker Laboratory

Bieker Laboratory

Bieker Laboratory

Bieker Laboratory

Regulation of Gene Expression During Erythropoiesis


Delineating the molecular events that confer the ability to express lineage-specific genes upon an initially uncommitted, pluripotent hematopoietic stem cell remain major questions in cell differentiation.  Use of an immortalized erythroid cell line as a means to isolate genes that may be important for erythroid function allowed us to identify a novel, erythroid-specific gene, which was named EKLF (erythroid Krüppel-like factor).

Biochemical, molecular, cellular, developmental, and genetic studies in mice and humans have established that EKLF is an essential component required for globin switching and completion of the definitive erythroid program. Disorders of hemoglobin expression can lead to a variety of hemoglobinopathies, including sickle cell anemia and ß–thalassemia (Cooley’s anemia). As a result, our examination of EKLF’s mechanism of action has illuminated how it regulates the globin locus, and has provided us with a way to reconstruct EKLF so that it can potentially rectify one type of hemoglobin disorder.

Our discovery of EKLF has stimulated other investigators around the world to search for analogous genes that can work in a similar fashion to regulate unique targets in other tissues.  EKLF is now the founding member (KLF1) of a family of eighteen proteins, some of which have been directly implicated in suppression of a specific subset of cancers.

Current Projects

We are vigorously continuing the study of EKLF (KLF1) using a number of approaches, including biochemical and structure/function analyses of the EKLF protein, identification of its protein partners, examining its ability to extrinsically control erythropoiesis, and monitoring how EKLF expression itself is so precisely regulated during development.

Our most recent studies are focused on a number of areas:
one, a continuing analysis of EKLF protein/protein interactions and how they result in altered transcriptional and epigenetic changes at target loci;
two, on how these controls converge to regulate late events in erythropoiesis, particularly enucleation;
three, on analysis of EKLF upstream regulators to help explain its exquisite tissue-restricted expression pattern, and to possibly link alteration of its expression level to aberrant red cell biology;
four, on functional and phenotypic analyses of a neonatal anemia mouse mutant (Nan) that contains a mutation in one allele of EKLF;
finally, on determining the mechanism by which a human mutation in EKLF leads to congenital dyserythropoietic anemia.


Selected Recent Publications

Xue L*, Mukherjee K*, Kelley KA, Bieker JJ. Generation, characterization, and use of EKLF(Klf1)/CRE knock-in mice for cell-restricted analyses. Frontiers in Hematology. 2024 2, 1292589. [*co-first authors] doi:

Chen X*, Pillay S*, Lohmann F, Bieker JJ. Association of DDX5/p68 protein with the upstream erythroid enhancer element (EHS1) of the gene encoding the KLF1 transcription factor. J Biol Chem. 2023 299, 105489. [*co-first authors]

Gnanapragasam MN*, Planutis A*, Glassberg JA, Bieker JJ. Identification of a genomic DNA sequence that quantitatively modulates KLF1 transcription factor expression in differentiating human hematopoietic cells. Sci Rep. 2023 13, 7589. [*co-first authors] [highlighted in Hematopoiesis News]

Mukherjee K, Bieker JJEKLF/Klf1 regulates erythroid transcription by its pioneering activity and selective control of RNA Pol II pause-release. Cell Rep. 2022 41, 111830.

Mukherjee K, Xue L, Planutis A, Gnanapragasam MN, Chess A, Bieker JJ. EKLF/KLF1 expression defines a unique macrophage subset during mouse erythropoiesis.  Elife. 2021 10, e61070. [highlighted in Hematopoiesis News]

Kulczynska K, Bieker JJ, Siatecka M. A Krüppel-like factor 1 (KLF1) Mutation Associated with Severe Congenital Dyserythropoietic Anemia Alters Its DNA-Binding Specificity.  Mol Cell Biol. 2020 40, e00444-19. [highlighted as an Article of Significant Interest]

Varricchio L, Planutis A, Manwani D, Jaffray J, Mitchell WB, Migliaccio AR, Bieker JJ. Genetic disarray follows mutant KLF1-E325K expression in a congenital dyserythropoietic anemia patient.  Haematologica. 2019 1042372-2380. [highlighted in Hematopoiesis News]

Gnanapragasam MN, Crispino JD, Ali AM, Weinberg R, Hoffman R, Raza A, Bieker JJ. Survey and evaluation of mutations in the human KLF1 transcription unit.  Sci Rep. 2018 8, 6587.

Planutis A, Xue L, Trainor CD, Dangeti M, Gillinder K, Siatecka M, Nebor D, Peters LL, Perkins AC, Bieker JJ. Neomorphic effects of the neonatal anemia (Nan-Eklf) mutation contribute to deficits throughout development.  Development. 2017 144430-440.  [highlighted as an In this Issue preview; highlighted in Hematopoiesis News]

Gnanapragasam MN, McGrath KE, Catherman S, Xue L, Palis J, Bieker JJ. EKLF/KLF1-regulated cell cycle exit is essential for erythroblast enucleation.  Blood. 2016 1281631-41. [highlighted in Hematopoiesis News]

Lohmann F*, Dangeti M*, Soni S, Chen X, Planutis A, Baron MH, Choi K, Bieker JJ. The DEK Oncoprotein Is a Critical Component of the EKLF/KLF1 Enhancer in Erythroid Cells.  Mol Cell Biol. 2015 353726-38. [*co-first authors] [highlighted in Exp Hem 43, 827 (15)]

Soni S, Pchelintsev N, Adams PD, Bieker JJ. Transcription factor EKLF (KLF1) recruitment of the histone chaperone HIRA is essential for β-globin gene expression.  Proc Natl Acad Sci U S A. 2014 11113337-42. [highlighted in Hematopoiesis News]

Xue L, Galdass M, Gnanapragasam MN, Manwani D, Bieker JJ. Extrinsic and intrinsic control by EKLF (KLF1) within a specialized erythroid niche. Development. 2014 1412245-54.

Selected Reviews

Mukherjee K, Bieker JJ. Transcriptional Control of Gene Expression and the Heterogeneous Cellular Identity of Erythroblastic Island Macrophages. Frontiers in Genetics. 2021 12756028.

Kulczynska-Figurny K, Bieker JJ, Siatecka M. Severe anemia caused by dominant mutations in Krüppel-like factor 1 (KLF1). Mutat Res. 2020 786108336. [highlighted in Hematopoiesis News]

Gnanapragasam MN, Bieker JJ. Orchestration of late events in erythropoiesis by KLF1/EKLF. Curr Opin Hematol. 2017 24183-190.

Perkins A, Xu X, Higgs DR, Patrinos GP, Arnaud L, Bieker JJ, Philipsen S. Krüppeling erythropoiesis: an unexpected broad spectrum of human red blood cell disorders due to KLF1 variants. Blood. 2016 1271856-62.

Manwani D, Bieker JJ. KLF1: when less is more. Blood. 2014 124672-3.

Yien YY, Bieker JJ. EKLF/KLF1, a tissue-restricted integrator of transcriptional control, chromatin remodeling, and lineage determination. Mol Cell Biol. 2013 334-13.

Siatecka M, Bieker JJ. The multifunctional role of EKLF/KLF1 during erythropoiesis. Blood. 2011 1182044-54.

Bieker JJ. Putting a finger on the switch. Nat Genet. 2010 42733-4.

Manwani D, Bieker JJ. The erythroblastic island. Curr Top Dev Biol. 2008 8223-53.

Bieker JJ. Krüppel-like factors: three fingers in many pies. J Biol Chem. 2001 27634355-8.



Kaustav Mukherjee
Assistant Professor

Sanjana Pillay
Postdoctoral Fellow

Tasleem Arif
Senior Scientist

Li Xue
Associate Scientist

Antanas Planutis
Lab Coordinator

We use biochemical, molecular, cellular, and developmental approaches to illuminate transcriptional and epigenetic controls that lead to regulated erythroid gene expression. Our focus is on both progenitors and late red cell stages, and in determining whether select transcription factor mutations are causative for aberrant or malignant mammalian hematology.

PI Collaborators

Anna Rita Migliaccio, PhD
Professor of Histology and Embryology
Università Campus Bio-Medico di Roma

Jeffrey Glassberg, MD, MA
Emergency Medicine, Hematology and Medical Oncology
Mount Sinai School of Medicine


James Palis, MD
Pediatric Hematology/Oncology
University of Rochester Medical Center
Rochester, NY 14642


Jan Frayne, PhD
Molecular Cell Biology
University of Bristol
United Kingdom


Eric E Bouhassira, PhD
Cell Biology and Medicine
Albert Einstein College of Medicine
Bronx, NY 10461



Aimola, Idowu
Africa Center Of Excellence On Neglected Tropical Disease
Ahmadu Bello University
Department of Biochemistry
Zaria Nigeria 810000

Chen, Joy
Cambridge, MA

Chen, Xiaoyong
Yale University School of Medicine
Dept of Pediatrics
333 Cedar St
New Haven, CT 06520

Chinta, Sree
Rutgers New Jersey Medical School
185 South Orange Ave
Newark NJ  07103

Dangeti, Mohan
Ascensia Diabetes Care
Valhalla, NY  10595

Gruzglin, Eugenia
UNIFIED, an Omnicom Company
New York, NY

Gnanapragasam, M Nithya
Cleveland State University
Department of Biological, Geological, and Environmental Sciences
Cleveland, Ohio 44115

Lohmann, Felix
Novartis Institutes for BioMedical Research

Lopingco, Tina
1400 Broadway, Floor 3
New York, NY  10018

Manwani, Deepa
Director of Hematology
Albert Einstein College of Medicine
Children’s Hospital at Montefiore
Pediatric Hematology/Oncology
3415 Bainbridge Ave
Bronx, NY 10467-2490

Miller, Ira J
Rush University Medical Center
Dept of Pathology
1653 W Congress Pkwy
Chicago, IL 60612

Quadrini, Karen
Passage Bio
One Commerce Square
2005 Market Street, 39th Floor
Philadelphia, PA 19103

Siatecka, Mirka
Adam Mickiewicz University
Institute of Experimental Biology
Department of Genetics
Umultowska 89
61-614 Poznań

Sengupta, Tanushri
Northwestern University
International Institute for Nanotechnology
2145 Sheridan Rd
Evanston, IL  60208

Soni, Shefali
Helmsley Charitable Trust
IBD/Crohn’s Disease Program
230 Park Avenue
New York, NY 10169

Stranahan, Alec
Bank of America Merrill Lynch
New York, NY  10036

Yien, Yvette
University of Pittsburgh
Department of Medicine
Vascular Medicine Institute
Pittsburgh, PA 15213

Zhang, Wenjun
Bristol Myers Squibb
311 Pennington Rocky Hill Rd
Pennington, NJ, 08534

Contact Us

Annenberg 2584
Phone: 212-241-5067
Office: 212-241-5067
Lab: 212-241-4143


Mailing Address
Mount Sinai School of Medicine
Box 1020
One Gustave L Levy Place
New York, NY  10029 

Postdoctoral positions are currently available.  Please email a CV, a summary of past experience, and a brief statement of research interests along with the names of two to three references.

Mailing Address
Mount Sinai School of Medicine
Box 1020
One Gustave L Levy Place
New York, NY  10029