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Education
- M.D. Capital Institute of Medicine, Beijing, P.R. of China
- Research Scholar, Dept. of Biochemistry and Molecular Biology, Medical College of Georgia
- Research Scholar, Dept. of Dermatology, Thomas Jefferson University
- Postdoctoral Fellow, Lab of Neuroendocrinology, The Rockefeller University
- Postdoctoral Associate, Lab of Molecular biology and genetic metabolism, The Rockefeller University
My interests are varied, but much of my work has been on a project studying cholesterol efflux from macrophages. It was determined that cholesterol efflux from a mouse macrophage cell line to exogenous apolipoproteins was dependent upon induction with cAMP analogues. I worked to catalog cAMP inducible genes in this cell line, which involved cloning, RNA preparations, Northern blots, and generating stably transfected cell lines. I co-authored a publication describing these cAMP inducible genes, one of which was ABCA1 (Takahashi, Y., Miyata, M., Zheng, P., Imazato, T., Horwitz, A., and Smith, J.D. Identification of cAMP analogue inducible genes in RAW264 macrophages. (2000) Biochem. Biophys. ACTA 1492:395-394). In order to confirm that ABCA1 was the responsible gene in this cell line, it was necessary to generate a stably transfected ABCA1 antisense cell line. I was involved in this project and was first author on a manuscript describing this work (Zheng, P., Horwitz, A., Waelde, C.A., and Smith, J.D. Stably transfected ABCA1 antisense cell line has decreased ABCA1 mRNA and cAMP-induced cholesterol efflux to apolipoprotein AI and HDL. (2001) Biochem. Biophys. ACTA 1534:121-128). I continued work on this project and created an ABCA1-GFP fusion protein expression vector; I also generated a stably transfected cell line that expressed the fusion protein constitutively. I recently finished the construction of a complicated gene-targeting vector, which will allow investigators to generate tissue specific ABCA1 knockout mice using the Cre-Lox methodology.
I have also found interesting results on a project to characterize a brain-specific enhancer near the apoE gene locus. This project began with an analysis of sequence similarities between the human and mouse genomes at the apoE gene locus. A region of >600 bp, about 50 kb downstream of the human apoE gene, was found that was 68% identical between the mouse and human genomes; this region was not in any genes, nor in the proximal promoter of any genes. Therefore, my colleagues hypothesized that this might be a regulatory element controlling tissue specific gene expression. I cloned this element into a reporter gene expression vector and, by transfection assays, showed that it did have enhancer activity in some of the tested cell lines. The data justified the testing of this element in transgenic mice, and I made the construction linking this element to an apoE gene fragment that did not contain any of the previously identified tissue specific enhancers. I characterized several lines of transgenic mice both from this construction and from a large apoE BAC clone of her making. Surprisingly, this element led to high level expression of human apoE mRNA and protein in the brain of these transgenic mice. Immunohistochemical studies showed widespread expression of the transgene in the brain, and double label immunofluorescent studies showed that the protein could be found in both astrocytes and neurons in the hippocampus and cortex. I am first author on a manuscript in preparation detailing this study (Zheng, P., Pennacchio, L.A., Rubin, E.M., Smith, J.D. A novel enhancer for brain expression near the human apoE gene locus. In Preparation).
Ping Zheng, Jonathan D. Smith: A novel-Distal Downstream Enhancers Direct Expression of the Human Apolipoprotein E Gene in the Brain. Manuscript.
Smith JD, Waelde C, Horwitz A, Zheng P. Evaluation of the role of phosphatidylserine translocase activity in ABCA1-mediated lipid efflux. J Biol Chem. (2002) 277:17797-803.
Ping Zheng, Andrew Horwitz, Jonathan D. Smith: ApoAI and ABCA1 colocalize cells during cholesterol efflux. American Heart Association Scientific Sessions 2001.
Ping Zheng, Andrew Horwitz, Jonathan D. Smith: Stabled transfected ABCA1 antisense cell line has decreased ABCA1 mRNA and cholesterol efflux to apolipoprotein AI and HDL. BBA 1534 (2001) 121-128.
Yukihiro Takahashi, Masaaki Miyata, Ping Zheng, Takayuki Imazato, Andrew Horwitz, Jonathan D. Smith: Identification of camp analogue inducible genes in RAW 264 macrophages. BBA 1492 (2000) 385-394.
Wang J, Alexander JT, Zheng P, Yu HJ, Dourmashkin J, Leibowitz SF: Behavioral and endocrine traits of obesity-prone and obesity-resistant rats on macronutrient diets. Am J Physiol 1998 Jun; 274 (6 Pt 1): E 1057-66.
Ping Zheng, Zhitong Liu, Jian Wang, Fee Lee, and Sarah F. Leibowitz: Obesity gene tubby interacts with a stress activated protein kinase. Society for Neuroscience 1997.
Zhitong Liu, Ping Zheng, John Ng, Sarah F. Leibowitz: Cloning of differentially expressed hypothalamic genes involved in the regulation of energy balance by representational differential analysis. Society for Neuroscience. 1997.
Mary M. Pomidor, Kimberly K. Ruhl, Ping Zheng, Yingjie Song, Rocky S. Tuan, and Norren J. Hickok: Relationship between ornithine decarboxylase and cytoskeletal organization in cultured human keratinocyte: cellular responses to phorbol-ester, cytochalasin B, and a-difluoromethylornithine. Experimental Cell Research. 221(2):426-37, 1995 Dec.
Mary M. Pomidor, Kimberly K. Ruhl, Ping Zheng, Yingjie Song, Rocky S. Tuan, and Norren J. Hickok: Relationship between ornithine decarboxylase and cytoskeletal organization in cultured human epidermal keratinocytes. Gordon Conference. Polymines, June 1995.
Yousufzai, S.Y., Ping Zheng, Abdel-Latif, A.A.: Muscarinic stimulation of arachidonic acid release and prostaglandin synthesis in bovine cilliary muscle: prostaglandin induce cyclic AMP formation and muscle relaxation. Experimental Eye Research, 58(5): 513-22. 1994 May.
Zhao X, Zheng P et al: Anemia due to glucose phosphate deficiency. One case. Chinese J. of Hematology. Vol. 13, No. 5, 1992.
Zheng Ping et al: One case acute hybrid leukemia chromosome changes and clinical features. Chinese J. of Hematology. Vol. 13, No. 7, 1991.
Zhao X, Zheng Ping et al: High dose immunoglubin treated refractory autoimmune anemia. Chinese J. of Hematology. Vol. 12, No. 7, 1991.
Zheng Ping et al: Aase syndrome. Chinese J. of Hematology. Vol. 10, No. 7, 1989.
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