Stem Cells, Vol 13, 135-145, Copyright © 1995 by AlphaMed Press

REVIEWS

Platelet glycoprotein IIb gene expression as a model of megakaryocyte- specific expression

KL Block and M Poncz
Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, USA.

Glycoprotein (GP)IIb/IIIa is an integrin complex normally restricted in its expression to platelets and the megakaryocytes from which they are derived. This complex functions as a receptor for fibrinogen and other ligands and is involved in platelet aggregation. The receptor complex is expressed at high levels during final megakaryocyte differentiation. Further, while GPIIIa is expressed in other tissues as part of the vitronectin receptor, GPIIb is only expressed on maturing megakaryocytes and the platelets derived from them. Thus studies of the GPIIb gene may serve as a model of gene regulation during this process. Over the past several years, the genes for both GPIIb and IIIa have been cloned and analyzed. The GPIIb gene contains 30 exons over 18 kilobases (kb). The transcriptional start site has been determined and there does not appear to be a TATA-box immediately upstream of this site. Studies have been done to define regulatory elements upstream of the transcriptional start site. Most of these studies focused on the human promoter and on studies using megakaryocytic cell lines. These studies have defined several important tissue-specific promoter elements including a GATA454 site (454 basepairs upstream of the transcriptional start site that involves a GATA-binding consensus sequence), a GATA54 site and an Ets35 site (that involves an Ets- binding consensus sequence). Expression studies with megakaryocytic cell lines suggest that each of these sites effects expression approximately threefold. Further, an Ets510 site was also described that had a similar effect. While these studies were underway, we pursued studies of the rat 5'-flanking region using a rat primary marrow expression system. Qualitatively, our data support the human data; however, quantitatively, we found significant differences from the human studies done in cell lines. We found that the major tissue- specific promoter element was the GATA454 site. Mutations altering this site result in an approximately fiftyfold drop in expression. In comparison, eliminating the Ets510 site by truncation or point mutation had only a twofold effect on expression. Mutations at the Ets35 site did effect expression at a high level, decreasing expression approximately fifteenfold, while mutations at the GATA54 site effected expression by approximately ninefold. In addition, using 50 bp deletions, we have preliminarily defined two domains from -450 to -351 bp and -150 to -101 bp upstream of the transcriptional start site that effected expression. The former appears to contain a positive regulatory element, while the latter appears to be a silencer element.(ABSTRACT TRUNCATED AT 400 WORDS)

This article has been cited by other articles:

				A. G. Muntean and J. D. Crispino Differential requirements for the activation domain and FOG-interaction surface of GATA-1 in megakaryocyte gene expression and development Blood, August 15, 2005; 106(4): 1223 - 1231. [Abstract] [Full Text] [PDF]

				P. Jackers, G. Szalai, O. Moussa, and D. K. Watson Ets-dependent Regulation of Target Gene Expression during Megakaryopoiesis J. Biol. Chem., December 10, 2004; 279(50): 52183 - 52190. [Abstract] [Full Text] [PDF]

				R. Zunino, Q. Li, S. D. Rose, M. M. I. Romero-Benitez, T. Lejen, N. C. Brandan, and J.-M. Trifaro Expression of scinderin in megakaryoblastic leukemia cells induces differentiation, maturation, and apoptosis with release of plateletlike particles and inhibits proliferation and tumorigenesis Blood, October 1, 2001; 98(7): 2210 - 2219. [Abstract] [Full Text] [PDF]

				M. Eisbacher, L. M. Khachigian, T. H. Khin, M. L. Holmes, and B. H. Chong Inducible Expression of the Megakarocyte-specific Gene Glycoprotein IX Is Mediated through an Ets Binding Site and Involves Upstream Activation of Extracellular Signal-regulated Kinase Cell Growth Differ., August 1, 2001; 12(8): 435 - 445. [Abstract] [Full Text] [PDF]

				P. Albanese, M. Leboeuf, J.-P. Rosa, and G. Uzan Identification of a GATA-overlapping sequence within the enhancer of the murine GPIIb promoter that induces transcriptional deregulation in human K562 cells Blood, August 15, 2000; 96(4): 1348 - 1357. [Abstract] [Full Text] [PDF]

				D. D. Spyropoulos, P. N. Pharr, K. R. Lavenburg, P. Jackers, T. S. Papas, M. Ogawa, and D. K. Watson Hemorrhage, Impaired Hematopoiesis, and Lethality in Mouse Embryos Carrying a Targeted Disruption of the Fli1 Transcription Factor Mol. Cell. Biol., August 1, 2000; 20(15): 5643 - 5652. [Abstract] [Full Text]

				M.A. Thornton, M. Poncz, M. Korostishevsky, E. Yakobson, S. Usher, U. Seligsohn, and H. Peretz The Human Platelet alpha IIb Gene Is Not Closely Linked to Its Integrin Partner beta 3 Blood, September 15, 1999; 94(6): 2039 - 2047. [Abstract] [Full Text] [PDF]

				C. Ody, P. Vaigot, P. Quere, B. A. Imhof, and C. Corbel Glycoprotein IIb-IIIa Is Expressed on Avian Multilineage Hematopoietic Progenitor Cells Blood, May 1, 1999; 93(9): 2898 - 2906. [Abstract] [Full Text] [PDF]

				L. S. Bastian, B. A. Kwiatkowski, J. Breininger, S. Danner, and G. Roth Regulation of the Megakaryocytic Glycoprotein IX Promoter by the Oncogenic Ets Transcription Factor Fli-1 Blood, April 15, 1999; 93(8): 2637 - 2644. [Abstract] [Full Text] [PDF]

				Y. Jin, C. C. Wilhide, C. Dang, L. Li, S.-X. Li, M. Villa-Garcia, and P. F. Bray Human Integrin beta 3 Gene Expression: Evidence for a Megakaryocytic Cell-Specific cis-Acting Element Blood, October 15, 1998; 92(8): 2777 - 2790. [Abstract] [Full Text] [PDF]

				J. A. Lopez, R. K. Andrews, V. Afshar-Kharghan, and M. C. Berndt Bernard-Soulier Syndrome Blood, June 15, 1998; 91(12): 4397 - 4418. [Full Text] [PDF]

				Y. Shou, S. Baron, and M. Poncz An Sp1-binding Silencer Element Is a Critical Negative Regulator of the Megakaryocyte-specific alpha IIb Gene J. Biol. Chem., March 6, 1998; 273(10): 5716 - 5726. [Abstract] [Full Text] [PDF]

				J. Birkmann, S. Oez, M. Smetak, G. Kaiser, H. Kappauf, and W. M. Gallmeier Effects of Recombinant Human Thrombopoietin Alone and in Combination with Erythropoietin and Early-Acting Cytokines on Human Mobilized Purified CD34+ Progenitor Cells Cultured in Serum-Depleted Medium Stem Cells, January 1, 1997; 15(1): 18 - 32. [Abstract] [Full Text]

				L. S. Bastian, M. Yagi, C. Chan, and G. J. Roth Analysis of the Megakaryocyte Glycoprotein IX Promoter Identifies Positive and Negative Regulatory Domains and Functional GATA and Ets Sites J. Biol. Chem., August 2, 1996; 271(31): 18554 - 18560. [Abstract] [Full Text] [PDF]

				K.-W. Kim, S.-H. Kim, E.-Y. Lee, N. D. Kim, H.-S. Kang, H.-D. Kim, B.-S. Chung, and C.-D. Kang Extracellular Signal-regulated Kinase/90-kDa Ribosomal S6 Kinase/Nuclear Factor-kappa B Pathway Mediates Phorbol 12-Myristate 13-Acetate-induced Megakaryocytic Differentiation of K562 Cells J. Biol. Chem., April 13, 2001; 276(16): 13186 - 13191. [Abstract] [Full Text] [PDF]

				B. P. Schick, I. Petrushina, K. C. Brodbeck, and P. Castronuevo Promoter Regulatory Elements and DNase I-hypersensitive Sites Involved in Serglycin Proteoglycan Gene Expression in Human Erythroleukemia, CHRF 288-11, and HL-60 Cells J. Biol. Chem., June 29, 2001; 276(27): 24726 - 24735. [Abstract] [Full Text] [PDF]